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HomeMy WebLinkAbout07/14/1992CITY COUNCIL AGENDA Mayor — Jay C. Kim Mayor Pro Tem — Phyllis E. Papen Councilman — John A. Forbing Councilman — Gary H. Werner Councilman — Gary G. Miller City Council Chambers are located at: South Coast Air Quality Management DistrictAuditonum 21865 East Copley Drive MEETING DATE: July 14, 1992 MEETING TIME: 7:00 p.m. Terrence L. Belanger Acting City Manager Andrew V. Arczynski City Attorney Lynda Burgess City Clerk Copies of staff resorts or other written: documentation relating to each item referrod o. on this agenda are on file in the C)ffice of the City Ckark and are a�ailahle for'public nspecfon If you haus questions regarding an. agenda item, please con#act theOity Clerk at (714) 860-»2489 during business hours. The City of Diamond Bar uses RECYCLED paper and encourages you to do the same. THIS MEETING IS BEING BROADCAST LIVE BY JONES INTERCABLE FOR AIRING ON CHANNEL 511 AND BY REMAINING IN THE ROOM, YOU ARE GIVING YOUR PERMISSION TO BE TELEVISED. Resolution No. 92-43 1. CALL TO ORDER: 7:00 P.M. PLEDGE OF ALLEGIANCE: MAYOR KIM ROLL CALL: Councilmen Forbing, Miller, Werner, Mayor Pro Tem Papen, Mayor Kim 2. PUBLIC HEARING: 7:00 p.m. or as soon thereafter as matters can be heard. 2.1 DRAFT GENERAL PLAN: The General Plan expresses a com- prehensive strategy for the management of growth and change within the community throughout the next twenty years. On June 9 the City Council began a series of public hearings on the General Plan. The purpose of the July 14 public hearing is to review final revisions to the General Plan. Recommended Action: It is recommended that the City Council receive testimony, review the final draft and adopt a resolution certifying the Environmental Impact Report and approving the General Plan. 3. ANNOUNCEMENTS: 4. CLOSED SESSION: Personnel - G.C. Section 54957.6 Litigation - G.C. Section 54956.9 5. ADJOURNMENT: 1. 2. 3. 4. 5. THIS MEETING IS BEING BROADCAST LIVE BY JONES INTERCABLE FOR AIRING ON CHANNEL 51, AND BY REMAINING IN THE ROOM, YOU ARE GIVING YOUR PERMISSION TO BE TELEVISED. CALL TO ORDER: PLEDGE OF ALLEGIANCE: ROLL CALL: 7:00 P.M. MAYOR KIM Councilmen Forbing, Miller, Werner, Mayor Pro Tem Papen, Mayor Kim PUBLIC HEARING: 7:00 p.m. or as soon thereafter as matters can be heard. 2.1 DRAFT GENERAL PLAN: The General Plan expresses a com- prehensive strategy for the management of growth and change within the community throughout the next twenty years. On June 9 the City Council began a series of public hearings on the General Plan. The purpose of the July 14 public hearing is to review final revisions to the General Plan. Recommended Action: It is recommended that the City Council receive testimony, review the final draft and adopt resolutions certifying the Master Environment Assessment and approving the General Plan. ANNOUNCEMENTS: CLOSED SESSION: Personnel - G.C. Section 54957.6 Litigation - G.C. Section 54956.9 ADJOURNMENT: CITY OF DIAMOND BAR AGENDA REPORT AGENDA NO. TO: Terrence L. Belanger, Acting City Manager MEETING DATE: July 14, 1992 REPORT DATE: July 9, 1992 FROM: James DeStefano, Community Development Director TITTLE: General Plan SUMMARY: DRAFT GENERAL PLAN: THE GENERAL PLAN EXPRESSES A comprehensive strategy for the management of growth and change within the community throughout the next twenty years. On June 9, the City Council began a series of public hearings on the General Plan. The purpose of the July 14 public hearing is to review the final draft of the General Plan. RECOMMENDATION: It is recommended that the City Council receive testimony on the General Plan, review the final draft, and adopt a resolution certifying the Environmental Impact Report and approving the General Plan. LIST OF ATTACHMENTS:_X Staff Report X Resolution(s) _ Ordinances(s) _ Agreement(s) Other EXTERNAL DISTRIBUTION: Library _ Public Hearing Notification _ Bid Specification (on file in City Clerk's Office) SUBMITTAL CHECKLIST: 1. Has the resolution, ordinance or agreement been reviewed X Yes _ No 2. by the City Attorney? Does the report require a majority or 4/5 vote? Majority 3. Has environmental impact been assessed? X Yes — No 4. Has the report been reviewed by a Commission? X Yes _ No Which Commission? Planning 5. Are other departments affected by the report? X Yes _ No Report discussed with the following affected departments: VIEWED BY: errence L. Belanger J es DeSb Acting City Manager Community Walnut Valley Unified School District 880 South Lemon Avenue, Walnut, California 91789 • (714) 595-1261 • Fax (714) 598-8423 • Ronald W. Hockwalt, Ed. D., Superintendent July 9, 1992 Diamond Bar City Council 21660 Copley Dr. Suite 100 Diamond Bar, CA 91765 Dear Mayor Kim, Council Members, Acting City Manager Belanger and Staff: The Board of Trustees and administration of the Walnut Valley Unified School District appreciate the opportunity to address the City Council on the Diamond Bar General Plan. We wish to focus our attention and your attention on Section 6, entitled "Public Services and Facilities„. It is our hope and request that statements in the General Plan addressing schools could be more extensive and specific. We have two requests regarding additions to the General Plan. Within Section D, you list the goals, objectives, and implementation strategies. We are requesting that Objective 1.3, which reads "To insure that all Diamond Bar residents have access to high quality local educational facilities regardless of their socio-economic status or location within the City” be expanded by adding an additional strategy 1.3.3. This strategy would state that future residential development would be linked directly to the availability of local educational facilities, i. e. schools. The rationale for this request is based on the fact that all schools in Diamond Bar are already overcrowded and while our bond monies will greatly expand our ability to provide housing, we still are nearly $50,000,000 short in adequately placing all students into permanent facilities and modernizing these facilities. Therefore, additional growth places yet another burden on housing of students in our school system. Our second request is that Site D not be designated as a proposed school site. The Walnut Valley Unified School District opposes the proposed designation as a school site since the property has never been used for school purposes and the school district has not determined how that property will be used in the future. To designate Site D as a school site based solely upon ownership is not appropriate in our opinion. We believe the General Plan should designate property on the basis of actual use or on its highest and best use and not merely ownership. This designation should be compatible with the development in the geographic area. Thank you for your consideration of these two requests. We hope that these two amendments can be made to the General Plan before its final approval. Thank you for your attention and for the opportunity to address you this evening. Most sincerely, Ronald W. Hoc alt, Ed. D., Superintendent Walnut Valley Unified School District mar oc: Board of Trustees RECEIVED DIAMOND DAR CITY C1.` PK Max Maxwell 3 211 Bent Twig Ln. 499; JUL 15 AM 8: 55 Diamond Bar, CA 91765 714 861-4121 Linda Burgess, City Clerk City of Diamond Bar 21660 E. Cop[ley Dr., Ste. 100 Diamond Bar, CA 91765 July 15, 1992 Linda Burgess, I am requesting a certified copy of the resolution for the Diamond Bar General Plan and EIR as passed by the City Council at the July 14, 1992 meeting. Please call me as soon as it is ready to pick up. Thank you, Max Maxwell 1 CITY COUNCIL REPORT AGENDA NO. 9.2 MEETING DATE: July 14, 1992 TO: Honorable Mayor and Members of the City Council FROM: Terrence L. Belanger, Acting City Manager SUBJECT: Review of the General Plan ISSUE STATEMENT: The General Plan expresses a comprehensive strategy for the management of growth and change within the community throughout the next twenty years. On June 9 the City Council began a series of public hearings on the General Plan. RECOMMENDATION: It is recommended that the City Council receive testimony on the General Plan, review the final draft, and adopt a resolution certifying the Environmental Impact Report and approving the General Plan. BACKGROUND: On June 9, 1992, the City Council began a series of public hearings as it prepares to adopt the General Plan. The Council received a report regarding General Plan requirements, preparation process, public participation and major policy considerations. The General Plan serves as a blueprint for the type of community desired for the future, and provides the means by which that future can be obtained. The General Plan expresses, in the form of text, maps and illustrations, the policies and programs necessary to create and maintain a functional, healthful, and desirable environment in which to work and live. The Diamond Bar General Plan will serve as a comprehensive strategy for the management of growth and change in our community throughout the next twenty years. The proposed General Plan addresses both the incorporated city limits and its adopted sphere of influence. The Draft Environmental Impact Report (DEIR) prepared for the Diamond Bar General Plan addresses the environmental impacts created by the Plan as well as mitigation measures for the impacts. The Draft Diamond Bar General Plan incorporates the seven required general plan elements (land use, housing, open space, conservation, safety, noise, and circulation) into five major sections: The Plan for Public Services and Facilities The Plan for Resource Management (Open Space, Conservation) The Plan for Public Health and Safety (Noise and Safety) The Plan for Physical Mobility (Circulation) The Plan for Community Development (Land Use, Housing) The City Council has conducted several hearings on the General Plan and has directed that certain revisions be prepared and incorporated into the document. The City Council has received the latest draft of the General Plan documents (policy plan, MEA, EIR, mitigation monitoring program). The final draft documents represent the cumulative total of all changes made during the public hearing review process as directed by the City Council. The purpose of the July 14, 1992, public hearing is to conclude review of the General Plan and its Environmental Impact Report, provide final comments on the documents and adopt a resolution approving the City's first General Plan. Prepares by Ja s DeStefa , Co i* Development Director attachments JDS\mco K M July 13, 1992 Max Maxwell 3211 Bent Twig Lane Diamond Bar, CA 91765 Dear Mr. Maxwell: 21660 EAST COPLEY DRIVE - SUITE 100 DIAMOND BAR, CA 91765-4177 714-860-2489 - FAX 714-861-3117 Pursuant to your verbal request of June 30, 1992, and written request of July 1, 1992, herein please find the explanation you seek to understand the referenced differences between the May 26, 1992 Draft General Plan and the Draft Plan dated June 26, 1992. Let me begin with a reiteration of my response to your questions provided during the June 30, 1992, City Council meeting. The published draft copy of the General Plan was completed as of May 26, 1992, to accommodate publication. The draft copy of the General Plan, contained within the summer edition Community Newsletter, was distributed to over 17,000 postal addresses within the community. The published draft focuses on the goals, objectives and action programming contained within the Plan. The Draft Copy of the Plan clearly stated the Planning Commission was in the process of revising the Draft prior to the beginning of City Council Public Hearings. The Planning Commission conducted eleven public hearings on the plan in April, May and early June, 1992. The Commission reviewed and revised documents in order to clarify the purpose, intent, understanding and implementation of the Plan. Attached to this letter please find a copy of your correspondence to me dated July 1, 1992, and page numbers 4, 7 and 8 of the Draft Plan (dated 5-26-92) with, for your convenience, notations referencing and responding to your comments. Hopefully, these notations provide the clarification you seek. If you have any other questions or comments on the General Plan, please contact me. Sincerely, Janes DeStefano Community Develo ment Director JDS1mco JAY C. KIM PHYLLIS E. PAPEN JOHN A. FORBING GARY G. MILLER GARY H. WERNER Mayor Mayor Pro -Tem Councdmember Councilmember Councilmember RECYCLED PAPER . the same in both versions... I personally asked for any reference to develop in Tonner Canyon be removed last week. I don't want the statement "sphere of influence" left in. 2. The Council's version of the (GP does not include the O following 2/3 page for the remainder of the page to the first bullet on page 8 as shown in the citizens version � all the way to "identify" now changed to "Designate" Kw"11v,l hillside areas etc... 1 PW_ 3. The Council's master copy of the GP has eliminated items I'm sure the public is concerned about suc s: 1. ... develop an on-going local news and interest programming—TV ... Community Calendars, discussion of local issues etc... These items are not included in the Council's GP. 4OW 1,7. 2, PAQP S- r% /AM! 2. Encourage organization of neighborhoods into smaller developments.. Oe while maintaining pedestrian and ���+ bicycle continuity and encourage eighborhood imyrov2Z= programs and social events." ..on and on "Maintain �•?.� residentials oprotect �r �, lifestvles as well as protect natural resources and rev 17 hillsides." 1 + d d 14 92 has these W T_�� The Land Use element from GPAC ate 4/ / items included as in the Citizens version. Note, the GPAC 4/14/92 version these items werer on page I-11 items 1.1.1 through 1.1.4. Special Note: Items missing in citizens version. See pg.4 of citizens version. Under Land Use Mix. at end of 2d para ending in: ... issue for the City rather than a property right. In the Council's version it has the following statement: W4VVXu. ;.r_5`12__ r ("Individual property owneres with large, hillside lots y also wish to re -subdivide their lots and. increase the number of allowable units.... Then the next sentence continues in both versions with: There are also different forms of open space. Why is this line not in the citizens version? MW{ Tr v — P005P Continuing a few paragraphs down down the citizens version to the 2d para under Economics: "The city could attempt to increase property tax revenue The next sentence is missing in the citizens version. Stated in a'Z� the document I received after last weeks Land Use Meeting that repres7ts the document that the Council is using,it states: s a means of increasing revenues the City could +tempt to increase property tax revenues by G establishing Diamond Bar as and exclusive community - I�h'iZt� This might bbg accomplished by signif iciant 1 Y lowering (41W ?,(0 • �Z allowable densities on remaining vacant land and encouraging development of remaining vacant lands as guarded -gated comunities From here on the statements are the same for both versions. I can't believe this is taking place. The "WR" public doesn't have any knowledge of this mis 4r) information. What is going on??? )WM pV Missing and inconsistent information is totally confusing, misleading and on the verge of fraud! Numerous errors that have been made. These are only a few WO -47- examples of this type of mi s -representation to the citizens of DB throughout this GP document. 2,'5.J2 3 Solution I ask this council to make the corrections, consistent with the strike out and addition policy that has been used, re -print the GP, re -circulate it to the public and allow the citizens enough time to review it word by word, paragraph by paragraph to verify what is actually in this legal document. Then, schedule another 4 or 5 meeting or even months of public hearings before you put this document to the final vote. Needless to say, I do not have the confidence that this plan is what the people of DB want. 4 4/ wvzwww -2. r3-tiv CRAFT COPY CrrY OF DIAMOND BAR GENERAL PLAN CITY COUNCIL PUBLIC HEARINGS: June 9, 16, 23, 30 July 7, 14 7:00 pm AOMD Auditorium 21865 E. Copley Drive, Diamond Bar, CA 1 For further information, please contact: City of Diamond Bar Community Development Department (714) 396-5676 The Drays complete as of May 26 to acoo MMC Process of making revisions to the 5 % h4ocw .i, 7.)5 �5Z The Planning Commission is Council Public Hearings. Community Developmut Issues The four land use issues identified in the Opportunities and Constraints section of the Existing Setting Report ( of �'eland and man-made environm nt to aopen c ace ommodate growth and economic implications); 2) capacitiess of the natural (infrastructure and service costs); 3) City image, including community design \ land use compatibility; and 4) local versus regional needs and short-term versus long-term solutions (especially concerning circulation). LAND USE MIX Open SpacePolicy The preservation of open spaces especially significant open or hillsie hillsidelareas left in the City, bu the City of Diamond Bar. There are several they are under increasing pressure to develoeviouslal r issue ar Some of these involves the status of restrictions against buildings p Y aapproved by the County open space areas were precluded from development open spa a requirition Of ementalfor the adjr an acent © nt tract. Often, these areas were calculatedP development, even though the County did not accept dedication. In some caze� diao�n al fAfWARi density was granted to the adjacent development in exchange for retaininghad these IrllwillW - space. These areas were often dedicated for environmental sts� �e County o reasons or because high hysical y constraints, and would create high maintenance SIJO 04* to the owner. As land becomes more valuable in Diamond Bar, these higher costs become less NOW of a restriction to development. 6N+Nh9 ••• It can be expected that the City will be asked to reconsider restriction to development o CAAFANOVWme of these lands previously designated for the City rather thanr or not these open property right,/ pace areas 1"t allowed to develop is a policy / a slope to �LW/There are also different forms of open space. For example, passive might gad area is to A4 create a pad of homes and a recreation area. While the natural, p Pespace PAG a man-made, active open space is created. In each case, the City must decide whaht type rde p n IN ` space best captures the community vision it wishes to create, while recognizing Pe - Q*+ deny of such factors as maintenance and fire protection costs. MV Orl ISSUE ANALYSIS.. The City should preserve to the maximum a majority of its CM464l, remaining open land MOM**, -Economics The City presently has a modest budget with a small operating reserve. However, municipal costs generally tend to increase faster than revenues, and service needs can be expected to increase faster than services can be provided. C► Therefore,governments have only two intima sources sts while seeking ways to increase City reven city g taxes from of revenue: local residents anf businesses. F om th sources, cities derive property both but sales tax revenues only ssesnues)while resale and new houses in �;,y could �•ee inerese proP�Y prices (slightly over $300,000), market research shows that home the City command fairly high p ' { gh Y PP al costs prices must exceed half a million dollars before )positionproperty tax 1978ecities roeceive� much lower for service. In addition, after the passage proportion of their revenues from local property taxes. Available data also indicates that lower 11U051'tOtN s,TA%VWJt Fwritiw PCM` D 0op � caUNu L afib • 23.91- h�N� Nom' b/M,49CW&t, 7, 07,1i '.. Goals objectives and Inokmmcation Strategies - Land Use W DpArr P'���p b• 2!o q "IT IS THE OVERALL GOAL OF THE PLAN FOR THE COMMUNITY DEVELOPMENT TO ENSURE THAT THE LAND USES AND DEVELOPMENT DECISIONS OF DIAMOND BAR ENHANCE THE QUALITY OF LIFE FOR ITS RESIDENTS, AND PRESERVE AND STRENGTHEN H"tqw CONOMIC STRUCTURE OF THE COMMUNITY." PA&5 IGOAL Maintain a mix of land uses which enhance the quality of life of Diamond Bar residents, T__1O consistent with their desire to maintain its quality and distinctiveness as a planned community. 1.7 Objective Stimulate opportunities for a diverse population cohesive to interact, exchange 1-17 ideas, conduct business, and establish and realize common goals. Strategies: Retain and provide community social gathering places, including active and natural park :r- t7 �.7• lands, community centers, and plaza areas within commercial and office complexes. (• ?� 2 In conjunction with public and private organizations, develop an ongoing local news and - interest programming in coniunction with local cable TV to include community calendars discussions of local issues, etc., factlttate mule -cultural programs and/or a community cultural festival.* CA � Pregular da - -for 1�,2� gZ MIA*�,•�,Z , a. Whenever possible, establish permanent loc Wiens ends) in the mind of the munpublity r7 events to improve attendance and firmly t( Encourage a "Community Calendar" as part of the local cable television programming :-17 to inform residents about the times and locations of upcoming community events. Where feasible within new large-scale developments, encourage a mixture of complemen- T-17 �•7• tary development types (e.g. residential, recreational, sales tax- and employment - generating uses) which can be provided in an integrated manner. Within new residential developments, encourage organization of neighborhoods into t _ 17 �•7� 4' smaller units and discourage non -local through traffic on local streets while maintaining pedestrian and bicycle continuity and encouraging neighborhood im rovement programs and social events. � � at-a€fer9•centralne� �ig}1 •nesidentsr•4-to � N11�1G ..cenveniettt aaci, csmpleiteasive se iee to-tke• eo�nn�rrit � �D ION — 5.22 • 92—' C,®MM Objective Maintain the high a9"1 of existing residential neighborhoods while offering a variety of suburban, urban, and rural horising opportunities. 't- p1 Strategies: tial developments, encourage a range of Where feasible and practical within residen • �- • housing types, which will appeal to a variety of household income groups, but with an 1- �- emphasis on single-family housing. 7/MOgCVt .1/ 7, ►3 ,`1 Z. �3Er Maintain a system of identifiable, complementary neighborhoods, providing, where appro- priate, neighborhood identity signage, and ensuring that such signage is well maintained over time. Maintain the integrity of residential neighborhoods by discouraging through traffic and fi_t-2_ preventing the creation of new major roadway connections through existing residential neighborhoods. 1.2.4 Maintain residential areas which provide for and protect rural lifestyles, as well as protect natural resources and hillsides. j •�t Identify hillsides that are appropriate for low density of residential development as Rural Residential (RR) on the Land Use map. The maximum gross density ( ftWO4 W A 9 of Rural Residential areas will be 1.0 dwelling unit per gross acre (1 du/acre). rVUWWW p • Development in Rural Residential areas should be designed to be: compatible with surrounding natural areas; compatible to the extent practical with surrounding t -12 5.28.92) L2.4A'development aesthetically pleasing and provide views from the development, but not at the expense of views of the development. Earthwork in Rural Residential areas should utilize contour or landform grading 1: —a - to be most compatible with the surrounding natural topography. • Development of Rural Residential areas should be clustered, or development • �v. density transferred to a more suitable site, wherever possible, to preserver I(o common open space or other natural resources. Such development should be located to coordinate with long-term plans for active parks, passive (open space) parks, and preserve natural open space areas. Maintain residential areas which provide for a suburban lifestyle, including ownership of single family housing. 1. I. I • b. • Identify the majority of Diamond Bar's residential areas, other than hillside or AWO rural residential areas, as Low Density Residential (RL) on the Land Use map. The maximum density of Low Density Residential areas will be 3 dwelling units per gross acre (3 du/acre). p �1-j • Identify older residential neighborhoods as Low -medium Residential (RIA) on M�,► the Land Use map. The maximum density of Low -Medium Residential areas will be 6 dwelling units per gross acre (6 du/acre). • ,Within areas designated for Low Density and Low -Medium Residential uses, limit land uses to single family detached residential, and small lot single family detached residential subject to applicable Diamond Bar General Plan policies, 1.2.5 . a • Development Code, and ordinance provisions. • Within areas designated for Rural Residential uses, permit the development of 111-9. b. second units and attached dwellings behind the primary residential structure, provided that: 1) the maximum density of the land use category is not exceeded; 2) adequate infrastructure is available to support the additional unit(s); 3) the additional unit is architecturally compatible with the primary dwelling unit and 8t Bl YA Wra-- 13-1Z. L Tt - Py of Dar rK)nd Mr wishas to rcw; csr�iti jFs trNa rwtstQOdirQ 6 ;v;fs of the �,�r�rr.! Ftnri . Q%L'a- V Cornmr.lea jGPAyC). This document rF4::le,on;s a si.IntTj(3j y of GPAZ:'s wc,,ic aver The past two years.` F0 ft Tly ,'F LkNIGND IV 16E0 E. CORTE/ 07;\'t ;AE '.7J ftiJlO-tiO SAR, CA 911765-3 1 ll 7 BY. V\IPJWG NETV11O,;K i 5 rOC'R':i ?12C!4liVJ L AVEiVUF is 7Ui V: H;, CUCAM3NGA, CA 91750 e 1, 1= p2 -- LIST OF FIGURES Figure 1-1 Regional Location ....................................... 1-2 Figure II -A-1 landforms........................................... II -A-2 II -B-2 Figure II -B-1 Regional Geology ..................................... Figure II -B-2 Local Geology ........................................ II -B-3 Figure II -B-3 Geologic Strata.......................................II-B-4 II -B-9 Figure II -B-4 Regional Faults ........................................ Figure II -B-5 Local Geologic and Seismic Hazards ......................11-B-10 Figure II -C-1 Drainage Basins ........... . ........................... 11-C-4 11-C-5 Figure II -C-2 Flood Hazards ........................................ II -C-6 Figure II -C-3 Adjacent Flood Plain ................................... Figure II -C-4 Flood Control Facilities ................................. II -C-10 Figure II -D-1 Plant Communities ..................................... II -D-4 Figure II -D-2 Biological Resource Areas (DF&G) .........................11-D-18 Figure 11-D-3 Significant Ecological Area 15 ........................... II -D-21 Figure II -E-1 Existing Land Use......................................II-E-8 Figure I1 -E-2 Photographs Key Map .................................. II -E-9 Figure II -E -2(a) Site Photographs ..................................... I1 -E-10 Figure II -E -2(b) Site Photographs.....................................II-E-11 Figure II -E -2-(c) Site Photographs.....................................II-E-12 Figure II -E -2-(d) Site Photographs.....................................II-E-13 Figure II -E -2-(e) Site Photographs ..................................... II -E-14 Figure 11-F-1 Historical Ozone Levels (Pomona Station) .....................11-F-6 Figure II -F-2 Air Pollutant Generation Breakdown ......................... 11-F-7 Figure 11-F-3 Sensitive Air Receptors.................................II-F-10 Figure II -G-1 Local Noise Levels.....................................II-G-4 Figure II -G-2 Noise Interference with Speech ............................II -G-5 Figure II -G-3 Land Use Compatibility with Noise .......................... II -G-9 Figure II -G-4 Railroad Noise Levels..................................11-G-11 Figure II -G-5 Background Noise Levels ............................... 11-G-12 Figure II -G-6 Sensitive Noise Receptors ............................... 11-G-17 Figure II -G-7 Interior and Exterior Noise Standards ....................... II -G-19 Figure II -H-1 Archaeological Resources ...............................II -H-3 Figure ll -K-1 Fire Protection Facilities..................................Il-K-4 Figure II -M-1 Local HazMat Routes...................................11-M-8 -Figure 11-N-1 Existing Park & Recreation Facilities ......................... II -N-7 Figure 11-N-2 Existing Open Space ................................... 11-N-9 Figure II -N-3 Trails..............................................II-N-11 Figure II -N-4 Neighborhood Park Deficiencies ..........................ll -N-16 Figure II -0-1 Educational Facilities...................................II-O-6 Figure Il -P-1 Water Facilities ........................................ II -P-4 Figure II -P-2 Reclaimed Wastewater System ...........................II -P-10 Figure i1 -Q-1 Wastewater Facilities...................................II-9-2 Figure II -S-1 Energy Facilities.......................................II-S-3 Figure II -T-1 Diamond Bar Functional Classification System ............... II -T-4 Figure II -T-2 Existing Daily Traffic Volumes ............................... II -T-15 Figure 11-T-3 Diamond Bar Major Intersection Locations and Deficient Peak Hour levels of Service ............................... II -T-20 Figure II -T-4 PM Peak Percentage of Through Trip Traffic ....................II -T-30 Figure 11-T-5 Existing Transit Service Routes ..............................II -T-37 Figure 11-T-6 Diamond Bar Existing Designated Bicycle Routes ................ II -T-40 Figure 11-T-7 Diamond Bar Proposed Equestrian Trail .......................II -T-42 Figure 11-T-8 Diamond Bar Designated Truck Routes ....................... II -T-43 Figure II -T-9 Year 2010 Average Daily Traffic Volume ...................... II -T-50 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11 LIST OF TABLES Table II -B-1 Modified Mercalli Intensity Scale .............................. II -B-11 Table II -B-2 Comparison of Richter Magnitude and Modified Mercalli Intensity ..... II -B-12 Table II -B-3 local Faults ............................................. II -B-13 Table II -D-1 Local Plants .................. . ......................... II -D-5 Table II -D-2 Local Wildlife ............................................ II -D-10 Table II -E-1 City -Wide Land Use........................................II-E-7 II -F-1 Local Air Quality (Pomona Station) .............................. II -F-4 .Table Table 11-F-2 Historical Air Pollution ....................................... II -F-5 Table II -F-3 Sensitive Receptors in Diamond Bar ............................. II -F-9 Table II -G-1 Environmental Protection Agency Guidelines ......................II -G-7 Table II -G-2 FHWA Noise Abatment Criteria ............................. II -G-8 Table II -G-3 Existing Noise Conditions....................................II-G-13 Table II -G-4 Local Noise Standards ..................................... II -G-18 Table II -G-5 Future Noise FHWA Analysis .................................. II -G-21 Table II -H-1 Local Historical Resources .................................... II -H-7 Table II -1-1 Population Age Breakdown....................................II-1-2 Table II -1-2 Regional Ethnicity (1980) ...................................... 11-1-3 Table II -1-3 Diamond Bar Ethnicity ........................................ 11-1-3 Table II -1-4 Household Composition......................................II-1-5 Table II -1-5 Income ($) ................................................II -1-5 Table II -1-6 Housing Stock .............................................. II -1-7 Table 11-1-7 Employment by Major Industry (1989 estimate) ...................... II -1-9 Table II -1-8 Employment by Land Use....................................11-1-10 Table II -1-9 Taxable Sales Per Capita 1989 ................................11-1-11 Table II -1-10 Taxable Sales Per Capita 1st Quarter 1990 .......................II -1-12 Table II -1-11 Taxable Sales Per Capita 2nd Quarter 1990 ......................II -1-13 Table II -1-12 Taxable Sales Per Capita 3rd Quarter 1990 .......................11-1-14 Table II -1-13 Taxable Sales Per Establishment 1989 ...........................11-1-15 Table II -1-14 Taxable Sales Per Establishment 1st Quarter 1990 ..................II -1-16 Table II -1-15 Taxable Sales Per Establishment 2nd Quarter 1990 ..................II -1-17 Table II -1-16 Taxable Sales Per Establishment 3rd Quarter 1990 .................. 11-1-18 Table II -J-1 Local Crime Statistics ....................................... II -J-2 Table II -K-1 Fire Protection Facilities .................................. 11-x-5 Table II -L-1 Local Hospitals ............................................. It -L-2 Table II -M-1 Sensitive Receptors Near HazMat Routes ......................... I1 -M-7 Table II -N-1 Regional Recreational Facilities................................II-N-2 Table II -N-2 Local Recreational Facilities .................................. II -N-6 Table II -N-3 Neighborhood Park Deficiencies ..............................II -N-15 Table II -N-4 Recreational Facility Standards ............................... II -N-17 Table II -0-1 Walnut Valley U.S.D. Facilities Serving Diamond Bar .................II -O-2 Table II -0-2 Pomona U.S.D. Facilities Serving Diamond Bar .....................II -O-5 Table II -0-3 Library Services ........................................... II -0-9 Table II -0-4 Projected School Needs....................................II-O-11 Table II -P-1 WVWD Water Quality.......................................II-P-5 Table II -P-2 Groundwater Quality.......................................II-P-9 Table II -Q-1 Sewage Generation Rates...................................II-Q-4 Table II -T-1 Daily Roadway Capacity Values ................................ 11-T-11 Table II -T-2 City of Diamond Bar Arterials Average Daily Traffic and Volume -to -Capacity Ratios ................................. II -T-12 - Table II -T-3 . Level of Service Interpretation .................................. II -T-17 Table II -T-4 AM and PM Peak Hour Level of Service at Signalized Intersections ..................................... 11-T-18 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 III LIST OF TABLES Table II -T-5 AM and PM Peak Hour Level of Service at Unsignal¢ed Intersections...................................II-T-23 Table II -T-6 Through Trip Traffic License Plate Survey Locations ...................II -T-25 Table II -T-7 PM Peak Percentage of Through Trip Traffic ........................ II -T-28 Table II -T-8 PM Peak Direction Through Trip Traffic Composition for Significant Arterial Segments ................................ II -T-31 Table II -T-9 Summary of Existing and Projected Land Use Within the City of Diamond Bar.................................II-T-45 Table II -T-10 Comparison of Estimated Daily Tripmaking .........................II -T-45 Table II -T-11 City of Diamond Bar Roadway Classification ....................... II -T-48 Table II -T-12 City of Diamond Bar Freeways Arterials Existing and Estimated Future Average Daily Traffic (Without Tanner Canyon Road) ................................. II -T-51 Table II -T-13 Future Average Daily Traffic and Volume -to -Capacity Ratios for Selected Arterials with and without Soquel Canyon Road/Tonner Canyon Road Extension ................ II -T-56 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 IV II. EXISTING SETTING A LANDFORMS AND TOPOGRAPHY 1. EXISTING SETTING a. Major Features The City of Diamond Bar occupies several connected valleys and rolling uplands in eastern Los Angeles County. The City is bounded by the Puente Hills to the west and north, and the Chino Hills to the southeast. The Puente and Chino Hills represent the northernmost extent of the mountains known as the Peninsular Ranges, which stretch south into Baja California. Diamond Bar generally comprises two southwest -northeast trending valleys. The central portion of Diamond Bar is a small upland of the Puente Hills, which is isolated from the surrounding Puente Hills by Brea Canyon Creek and Diamond Bar Creek. Brea Canyon Creek comes north out of Orange County into the east San Gabriel Valley. It travels north along the Orange (57) Freeway, then angles to the northeast to follow Diamond Bar Boulevard. Diamond Bar Creek comes east out of the Los Angeles basin, generally following the Pomona (60) Freeway. The valleys formed by Brea Canyon and Diamond Bar Creek represent two main passes into Diamond Bar (from the south and west, respectively). Other local passes in and out of Diamond Bar have been used for major roadways. The Spadra Pass, at the for north end of the City, contains the 57 Freeway and Mission Boulevard. The Phillips Ranch Pass contains the 60 Freeway as it travels out of Diamond Bar into Chino. Grand Avenue also passes east out of the City through a gap (Grand Avenue Pass) between the Puente Hills and the Chino Hills, crossing the upper end of Tanner Canyon near the old Arnold Reservoir (USGS 1981). The City contains several isolated canyons and surrounding upland areas, including Sandstone Canyon (west of the 57 Freeway, north of Pathfinder) and Upper Sycamore Canyon (between Diamond Bar Boulevard and Leyland, north of Grand Avenue), among others. b. Elevations Within the City limits, elevations range from a low of 500 feet above mean sea level (amsq up to 1470 feet amsl. In general, elevations increase from south to north and from west to east. The lowest area of the City is along the western border, where the 60 Freeway first enters the valley. The higher elevations are conversely found in the northeastern corner of the City. This high, rolling 'plateau' south of the 60 Freeway is called the Tres Hermanos area. This area not only boasts the highest elevations within the City, 4 also contains the'headwaters' of the Tanner Canyon drainage. The Puente Hills generally occupy the western half of Diamond Bar Valley, but are split by the 60 Freeway. South of the freeway (west of Brea Boulevard), elevations rise from 600 feet amsl at the freeway to 1075 feet amsl at Diamond Hill (site of Ronald Reagan Park). These areas also contain several undeveloped or largely undisturbed slopes (east of Canyon Ridge Road and Quail Run Drive) and canyons (Sandstone Canyon, north of Pathfinder). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -A-1 P O O O P v1 O O tE 0 W y W )P; N w (LU V P O O O P v1 O O tE 0 W y Along the western side of the combined 57/60 freeways, elevations rise from 600 feet omsl at the freeway interchange to almost 900 feet amsl where the two freeways again separate. Although these low, rolling hills are actually within the City of Industry, they are very visible to people traveling on the freeways as well as to local residents. Views of these currently undeveloped hills (and any development they eventually support) would reflect on the overall views of Diamond Bar (see Recreation and Open Space). The Puente Hills also pass through the center of Diamond Bar, but are split by Diamond Bar Creek (60 Freeway) and Brea Canyon Creek (57 Freeway). Elevations in the central part of Diamond Bar range from 700 to 1,100 feet amsl. In the northeastern portion of the City, elevations within the City reach 1,116 feet amsl, although elevations further to the north, beyond the City limits, reach almost 1160 feet amsl at Elephant Hill, just north of Temple Avenue and the 57 Freeway. East of Diamond Bar Boulevard and south of Grand Avenue, a private, gate -guarded community called `The Country has been developed among the rolling hills and canyons. Elevations range from 700 feet at the 57 Freeway and Diamond Bar Boulevard, up to 1,119 feet along the San Bernordino/Los Angeles County line. The Chino Hills generally occupy the southeastern portions of the City, including the City's sphere of influence. The sphere of influence occupies a large portion of the Tanner Canyon drainage immediately south of the City limits, which is also south and east of "The Country" development. Elevations range from 680 feet amsl at the point Tanner Canyon passes into Orange County, up to 1,405 feet amsl at Rowland Hills, along the southeast ridge of the canyon. C. Slopes Slopes vary tremendously throughout Diamond Bar. Numerous canyons, washes, and inter -connected valleys produce a variety of gentle to steep slopes within the City, as well as in the sphere of influence. While slopes near the lower (western) end of Diamond Bar Creek are fairly gentle (2-10 percent), slopes in its upper reaches, in the northern end of the City, can sometimes exceed 25 percent. Slopes along Brea Canyon Creek are more gentle close to the stream channel, but also become steep in many places, often exceeding 25 percent in some of side canyons along the western side of "The Country" development. Slopes can vary from almost flat on hilltops and along ridgelines, but con quickly plunge down along small drainage courses, creating steep slopes adjacent to many level areas, such as along the southeastern side of The Country development. The terrain in the sphere of influence (Tonner Canyon) consists mainly of native rolling hills, with slopes often exceeding 25 percent. 2. ISSUES AND OPPORTUNITIES Most of the lands within the City limits, especially the flotter portions, have already been developed. However, there are several issues the City will need to consider as development proceeds on the remaining undeveloped areas. Residents have expressed the desire to promote aesthetically pleasing open spaces and natural slopes within the City. Preservation of prevailing densities and open spaces could benefit the Diamond Bar quality of life by protecting remaining viewsheds and preserving the natural character of remaining hillsides. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -A-3 The historical pattern of development in Diamond Bar under the County was to significantly modify ridges and hills. The major advantage of this was it allowed for the greatest number of pads and maximized the number of view -oriented homes. The major disadvantage of this pattern was it created largely artificial appearances, with homes and manufactured 2:1 slopes being the predominant sights from nearby areas. As one resident explained, "Diamond Bar is a place to look from, not a place to look at". The City could choose to continue this historical development pattern, which would continue to provide outstanding views for new homeowners. Continuation of the historical pattern of development could also cause greater impacts on biological resources: can lead to loss of natural open space (including slopes): and create a more artificial, urbanized visual environment in the City. However, the City has recently adopted an interim hillside grading ordinance to be more sensitive to the natural topography. Emphasis on preserving natural contours would create beneficial views of hillsides for existing residents, instead of creating homes and views of hillsides for new residents. More emphasis on natural contours would however create various tradeoffs in the development process. Preserving areas that are presently vacant will reduce the overall level of development that can occur. Although this may result in fewer numbers of units, the landform modifications necessary to achieve this look will have to be different from those historically used. The two primary methods of preserving areas with rolling terrain are: Contour or landform grading to create hillsides that have a natural appearance by emulating existing contours, and Clustering or concentrating development on flatter areas, or away from hillside areas that will be preserved. For example, instead of cuffing away half of a ridge to fill the adjacent valley (and form the most level pads), just the top of the ridge could be leveled, with the surrounding native slopes preserved as permanent open space. This would allow fewer units to be built, and also produce views for fewer new residents, but would maintain open space views for existing residents. It should be noted that preservation of ridgelines often forces development into the canyons, which off on have more significant biological resources, but are more prone to flooding. Contour grading creates hillside views that appear natural. However, this is not the only type of open space the City could encourage. Development can also emphasize useful open space in contrast to natural hillsides. For example, a project may create a linear or meandering greenbelt for use by its residents instead of creating natural -looking hillsides that are visible from surrounding areas. Higher -density projects that cluster units in flatter canyon areas may emphasize natural or contour -graded slopes that surround the development. In contrast, a lower density project along a ridgellne might wish to create greenbelts or other open spaces for residents in lieu of hillsides that are visible from neighboring areas. Private or public parks are also a type of open space that should be considered when making decisions about specific projects. It is therefore necessary to determine what actually constitutes open space as part of the General Plan process. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -A-4 Providing Open Space The City must first determine the actual status (i.e. development potential, If any) of remaining public and private open space. The process of actively preserving open spaces then involves the following steps: • Defining Open Space There are many different kinds of open space that can be encouraged in Diamond Bar. Natural types include undisturbed hillsides, canyons, and ridges. Man-made open spaces can range from graded hillsides that appear natural, to greenbelts or more level landscaped areas that can be used by nearby residents (public or private). Active recreational areas such as parks, that can be utilized by all City residents, should also be considered. The City should determine which of these types of open spaces it wishes to emphasize as development continues in Diamond Bar. Open Space Inventory To actively preserve or protect remaining open lands, potential preserve areas need to be Identified, Including their size and other characteristics that lend themselves to preservation (biological resources, flood hazard areas, etc.). Based on these characteristics, areas can be prioritized in order of importance. During this process, areas that already have severe building constraints (such as unstable slopes), or that contain important environmental resources (such as riparian vegetation) should be emphasized to achieve multiple goals of the City. It is also beneficial to work with property owners to identify portions of potential preserve areas that are appropriate for development. In this way, the owner's ability to develop has been redirected, but not prohibited, and areas with limited development potential and environmental resources (such as views) can be preserved as a community resource. • Resources vs. Constraints The desire to preserve open lands, important resource areas, etc. must be carefully weighed against various legal and practical considerations and development constraints such as a property owner's right to develop, amount of developable land, flooding problems, biological resources, slope or seismic stability, etc. Natural londforms or areas with multiple environmental resources and/or constraints against building should receive a high priority for preservation, such as: Steep and/or unstable slopes (see Section II -B, Earth Resources and Seismicity) Slopes, ridges, shoulders, or high points visible from freeways, major roads, or areas with large numbers of homes (see Section II -N, Recreation and Open Space) Hillsides or canyons with significant chaparral, sage scrub, oak woodland, riparian, or other sensitive native vegetation (see Section II -D, Biological Resources) Adjacent to existing or proposed parks (see Section II -N, Recreation and Open Space) or Important biological resource areas (see Section II -D, Biological Resources). B is important to recognize that with increasing land values and advancing technology, those factors traditionally considered development constraints tend to diminish. Consequently, it is local conservation and development policies, and not physical constraints, that will dictate future development patterns in the City. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -A-5 Prioritizing Open Lands The process of prioritizing open lands for potential preservation involves weighing their various resources against their constraints for building, relative to the property owner's right to develop. If the City decides to preserve open lands, it will first have to determine what kinds of natural areas should be preserved (i.e. canyon bottoms, slopes, ridgelines, etc.). For example, in a fairly flat canyon, the bottom is most easily developed, but often contains mature trees, provides support for native wildlife, and is more subject to potential flooding than hillside areas. The hillside shoulders and ridges can be cut down to make large pad areas with good views, but are most visible from surrounding existing development and change the overall "contour" of the ridgeline. Cutting higher areas usually means filling in adjacent canyon or slope areas to create additional pads. However, slopes can be unstable or valuable as biological habitat. Natural slopes also represent fire dangers when covered with dry native brush. Contour grading along existing ground levels can minimize the visual changes to the landforms, but reduce the number of units that can be built. The various building constraints and/or environmental resources of each area must be weighed relative to each other including the owner's right to develop some portion of the property. The City may wish to consider the following areas (among others) within its boundaries for potential preservation: Slopes and/or canyons west of the 57 Freeway, both north and south of Pathfinder: - east and south of South Pointe Intermediate School (Sandstone Canyon) - east of Canyon Ridge Road - east of Quail Run Drive - along the west side of Brea Canyon Cutoff Road (potential annexation area), Canyons and hillsides west and northwest of Summit Ridge Park, between Diamond Bar Boulevard and Leyland (Steep Creek and Upper Sycamore Canyon), Slopes behind the Gateway Corporate Center, off of Copley and Bridge Gate Drives, Pomona Hills in the Tres Hermanos area (highest point in the City). Slopes/ridges in the Tres Hermanos area, especially those in the northwest corner, containing significant oak or chaparral vegetation, or those associated with Upper Tonner Canyon (see Section II -D, Biological Resources). Determining the Need for Man-made Open Space Undeveloped areas with hillsides visible from surrounding areas would not have to be preserved intact. Contour grading can be utilized on natural slopes. In some areas, it might also be beneficial to regrade selected manufactured slopes to more natural contours. These areas need to be identified and evaluated relative to available legal mechanisms, development potential, and grading constraints. An analysis of parkland needs should be integrated into this open space process so that both active and passive recreational needs of the community are met along with providing open spaces within Diamond Bar. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -A-6 Strategies for Providing Open Space The City could investigate transferring development density from possible preserve areas to other portions of a property, this would still allow development while protecting open lands. The City may also wish to purchase land for preservation, although this is an expensive method of protection. An in -lieu fee could be assessed on all new development, although this may be inadequate for a major acquisition program. Each development could also be required to provide its own open space, either in the form of contour -graded hillsides, greenbelts, or parks. The City could also participate in a non-profit land bank consortium with other public agencies for the purpose of purchasing open lands for preservation. Sphere of Influence Tonner Canyon, within the City's sphere of influence, contains numerous hillsides and prominent landforms that represent a unique resource for this entire three county area. This area should be given special consideration in terms of landform preservation as it will also help protect and preserve the important biological resources that utilize the canyon. This area may need special studies to determine the most important features for preservation. Contour grading should be used in areas to be developed. Ultimate land uses in the canyon should be planned to minimize impacts on these resources. Outlying Areas In addition, there are three areas just outside of the City limits or sphere of influence that could significantly affect views of hillsides from the City. The first area consists of low, rolling hills - northwest of the 57/60 freeways at Grand Avenue. While these hills are within the City of Industry, they are a prominent visual port of the Diamond Bar valley. The City of Industry has plans for Industrial business park uses in this area, and its development would create a significant change to existing views along the freeway corridor within Diamond Bar. At a minimum, the City may wish to review and monitor development in this area to minimize potential visual impacts. The City might also wish to express its concerns to the City of Industry to seek opportunities to foster development In this area that would be sensitive to man-made views. The second area is the portion of Tonner Canyon mainly south of Grand Avenue, northeast of the City's sphere of influence, up to the Tres Hermanos area. This area represents a significant landform adjacent to the City, but is actually located within the community of Chino Hills. The Chino Hills Specific Plan calls for this area to be a low density rural village with significant open space. However, its progress, and any changes to the development plans, should be closely monitored to assure that no unanticipated visual impacts accrue to the City. As with the first outlying area, the City may wish to work with the Chino Hills Municipal Advisory Committee (MAC) and the County of San Bernardino to explore opportunities to protect future views and open space in this area. The third area is Lower Tonner Canyon, where it intersects the 57 Freeway. Although this area is with Orange County, it will one day represent a gateway to Diamond Bar, as that portion of Tonner Canyon within the City's sphere of influence is developed. The City of Brea is currently undertaking a Sphere of Influence study to determine the appropriate development for the Tonner Canyon. This study is anticipated for completion in early 1992. The City may wish to work with the City of Brea to best plan for adequate planning and preservation of Tonner Canyon as a whole. Such an extensive planning effort may involve the formation of a joint study group to address ultimate land uses in the Canyon. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -A-7 B. EARTH RESOURCES AND SEISMICITY ExIsnNG SETTING a. Regional Geology At the beginning of the Miocene period (25 million years ago) this portion of southern California was a vast inland ocean over 3 miles deep. During this time, marine sediments thousands of feet thick were laid down. As time passed, the upthrusting geologic pressures transformed the area from a deep sea to a shallow sea late in the Miocene period (11 million years ago), then eventually to a continental area during Pliocene times (2.5-11 million years ago). In more recent Holocene times (the last 11,000 years), alluvial (stream -deposited) materials have been laid down in canyons and along drainage courses (LADCE 1980). Diamond Bar Is part of a dynamic geological region. Figure II -B-1 shows the geology of this region. b. Local Geology Diamond Bar is underlain by sedimentary rocks of the Puente Formation. These rocks were formed by the compression of marine silt and sediments during Miocene times. They consist of moderately consolidated siltstones and sandstones and are highly weathered in all natural exposures. The Puente Formation attains a thickness of more than 13,000 feet in other portions of the San Gabriel Valley. More recent alluvial sediments overlie the sedimentary rocks in some areas, although most are residual due to centuries of erosion and mass wasting (landslides). There is no evidence of Igneous or metamorphic rocks in the immediate area (LADCE 1980), as are found closer to the San Gabriel Mountains to the north. Figure II -B-2 shows the local geologic formations present within Diamond Bar, while Figure II -13-3 shows their relationship to geologic time. The Puente formation is divided into four main members, but only the following three lower members are found in Diamond Bar (the Sycamore Canyon member is absent in Diamond Bar): • La Vida Member (Tpl) This is a shale and siltstone containing calcium or silica. It is easily split into sheets or layers. Hard, limy concretions, lenses, or beds occur intermittently. It may contain a significant amount of soft, micaceous, somewhat massive siltstone. It also contains a silty, medium -grained, generally thinbedded siltstone or cross -stratified, arkosic sandstone. Interbedded siltstones off en contain microfossils and fish scales. The La Vida Member is found in the northern and southern upland areas of Diamond Bar. Soquel Member (Tps) This is a massive to well -bedded sandstone with interbedded siltstone and lenses of conglomerate. It is medium to coarse-grained and is somewhat easily broken into fragments. As with the La Vida Member, it is generally exposed in the northern and southern uplands in the Diamond Bar area. Yorba Member (Tps) This material is primarily siltstone but can contain silica or mica. Due to this variety of constituents, the physical properties of these materials can vary from poorly bedded to well -bedded, consolidated to easily split into sheets or layers, or extremely soft to hard. Some sandstone also occurs locally, as well as minor amounts of Dolomite (commonly called limestone or marble). B is found in the eastern and central portions of Diamond Bar. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-1 4� -C 0 0 Z HHv KIo ca D.7- 0 0 4 z 0 0 0 0 C) -.8 z .0 z-, � < "At f < t, CC 0 Z Y 0 0 -le LLJ 1(2 u 4� -C 0 0 Z HHv KIo ca D.7- 0 0 0 0 cc LLI "At 0 4� -C '5 0 Z HHv KIo 4� -C M" l MIN � / » U O O (D k U O §4 ! k\ � \� WOOD � Z 2 § ± k ! 7 LLJZ )3 § s w _ \222 » U O O (D k U O §4 ! k\ � \� WOOD ) [� \ � § 2 § ± k ! 7 )3 § s \222 /p m ) [� \ GEOLOGIC TIME FRA PERIOD EPOCH MILLION YEARS nS STRATIGRAPHY FIGURE II -B-3 FORMATIONS SOURCE: - Geologic -Seismic Study, Diamond Bar General Plan, Department of the Los Angeles County Engineer, 1980. CANNING NEl1M1ORK GEOLOGIC STRATA §1111AHOW BAR 0 Holocene Artificial Fill (a9 (Recent) Recent Alluvium (Q01) 0.01 (11.000 yrs) <1,000 Older Alluvium (goat) ='_ ' Quaternary Pleistocene U 2.5 1,000 0 Pliocene Z W U 11 2,000 Puente Formation (fp) Miocene La Vida Member UM 25 4,000 I Socluel Member (Tps) Yorba Member (Tpy) Tertiary Oligocene 40 8,000 Eocene 60 Poleocene 70 10,000 Cretaceous U � O 135 15,000 Cn LU Jurassic 180 +20,000 SOURCE: - Geologic -Seismic Study, Diamond Bar General Plan, Department of the Los Angeles County Engineer, 1980. CANNING NEl1M1ORK GEOLOGIC STRATA §1111AHOW BAR 0 In summary, the bedrock formations underlying Diamond Bar are relatively weak and subject to failure in many locations. They contain a variety of microfossils, although the location of deposits are difficult to predict. In addition to the Puente bedrock formations, there are various sediments that have been recently deposited in the Diamond Bar area. These can be classified into three main types: • Older Alluvium (goal) The older alluvial materials are from Pleistocene times (1-3 million years ago) and are distributed on the uplands bordering Brea Canyon, in the southern part of the City. These deposits consist of semi -consolidated, poorly sorted, clayey gravel, sand, and silt. The soils overlying these deposits are generally thick and reddish brown. Recent Alluvium (Qal) This younger alluvial material consists mostly of unweathered, unconsolidated, gravel, sand, silt, and clay. These materials are poorly sorted and crudely layered. Finer grained materials are generally found further away from hillsides, with deposits as deep as 100 feet thick in some drainage courses. These materials are mostly found in the southern portions of Brea, Diamond Bar, and Tonner canyons. Minor amounts of alluvium occur along the bottom of all the canyons in the Puente and Chino hills. Artificial Fill (Qaf) Most of the artificial fill in Diamond Bar is compacted. In general, fill materials newer than 1960 and associated with developed areas (i.e. graded lots or roads) are compacted adequately, such as those associated with the 57 and 60 freeways. However, fills associated with older roads, such as Brea Canyon, or with development prior to 1960, are generally uncompacted (LADCE 1980). Fills related to development in the west central part of the City have been compacted to Los Angeles County Grading Ordinance standards. It should be noted that Figure II -B-2 only shows the location of large fills, or fills placed in large canyons. Many areas of the City contain native soil materials that are limited when used for construction or to support structures. Areas that have been properly prepared (i.e. cut or hard compacted filo are generally suitable for development. Large amounts of uncompacted fill material may also be located in the sphere of influence area of Tanner Canyon as a result of historical oil production activities (LADCE 1980). The sediments previously described are derived from local rocks (primarily sandstones and siltstones) by natural processes such as wind erosion, water erosion, sloughing, biological activity, etc. These weathered materials form the basic soil elements that cover the Diamond Bar area. C. Local Soils Local soils are derived primarily from erosion of the surrounding uplands, producing a variety of soil types. The three local members of the underlying Puente Formation are comprised of various siltstones and sandstones containing calcium, silica, and mica. These materials are weakly bedded, and their erosion contributes to the formation of the major soil groups found in the Diamond Bar area. While many hillside areas contain little or no topsoil cover, local soils fall into two broad classes: uplands, and alluvial valleys, fans, and terraces. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-5 The uplands comprise soils of the Saugus-Fontana-Nocimiento and Gaviota-Rock Outcrop associations. Specific local upland soils include several Nocimiento clay loams and Gaviota sandy looms. These soils have various limitations for building depending on their individual slope and physical characteristics. These soils often contain mica or silica, or interbedded layers of clay or silt that can contribute to slope failure if penetrated by water or triggered by groundshaking (refer to Local Faults. later In this section). A number of undisturbed native slopes support soils with a very dark -colored natural humus -like material. This soil condition is referred to as "black earth" and is found along the south and southeast -facing slopes of Tonner Canyon, within the southern end of "The Country' development. Soils in the alluvial valleys mainly comprise the Ramona-Chualar-Sorrento association, in addition to -members of the Saugus-Fontana-Nocimiento soils washed down out of the foothills. Specific local alluvial soils include several Fontana, Sorrento, and Chualar clay looms, and Garretson sandy looms. While some of the alluvial soils, such as Chualar clay looms in Tanner Canyon, could support limited agriculture, most of these soils would not readily support economical agricultural operations, particularly on the steeper slopes. Presently, a number of upland soils do support grazing, such as in the Tres Hermanos area (SCS 1969). Many of these soils contain sufficient clay and silt materials to pose potential hazards from liquefaction and differential settling. These conditions have the highest probability of occurring where groundwater levels are high, usually along the Brea Canyon, Diamond Bar Creek, and Tanner Canyon watercourses. d. Regional Faults Southern California and Diamond Bar rest upon the Pacific Plate, which is moving northward past the adjacent North American Plate at a rate of a few inches each year. The pressure caused by these moving plates creates tremendous strain in the earth's crust, which in turn causes cracks or fissures (called faults) in the crust. The pressure between the Pacific and North American Plates has formed the San Andreas Fault Zone. The San Andreas is a classified as a "right lateral" fault. At its closest point, the San Andreas Fault Zone is located 25 miles northeast of the City of Diamond Bar. The strain in this and other local fault zones is periodically released by sudden movements of the earth, which are called earthquakes. The Los Angeles Basin is crisscrossed by numerous regional earthquake faults, which divide it into smaller geologic "blocks". Diamond Bar is located near the southern border of the Northeastern Block. The southern border of this block is defined by the Whittler Fault, just south of the City's sphere of influence (Tonner Canyon). The San Gabriel Mountains and the active San Andreas and Cucamonga faults form the northern border of the block, while the Puente Hills and the potentially active Chino fault border it to the east (see Figure II -B-4). The term "active" refers to faults that have moved during Holocene time (about the last 11,000 years), while "potentially active" refers to faults that have not moved during Holocene time, but have been active during Quaternary time (11,000 to 3,000,000 years). "Inactive" faults are those which have riot demonstrated movement within Quaternary time. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -B-6 The Northeastern Block contains five active regional faults; the San Andreas, Newport -Inglewood, Reymond Hill, San Fernando, and Norwalk Faults. R also contains eight potentially active faults; the Whittier, San Gabriel, Santa Monica, Sierra Madre, Son Jose, Malibu Coast, Verdugo, and Walnut Creek Faults. Of these, only the nearby Whittier Fault Zone has been mapped in the immediate vicinity of the City; in Tonner Canyon near the 57 Freeway, immediately south of the City's sphere of influence (see Figure II -B-4). G. Seismic Study Zones To minimize human injury and structural damage from active and potentially active faults, the State of California has adopted the Alquist-Priolo Special Studies Zones Act. Signed into law on December 22, 1972 and effective March 7, 1973, this act required the State Geologist to map "Special Studies Zones' along the State's active and potentially active faults. Prior to approval of structures for occupancy within these zones, a geologic study must be undertaken to determine the precise location and necessary setbacks from identified faults. In addition, individual cities and counties can establish special or hazard management zones for faults that may not quality as significant at the State level, but which may still represent a local seismic concern (Fault -Rupture Hazard Zones in California, CDMG, 1988). At present, no portion of the City of Diamond Bar is located within any special seismic study or hazard zone, as defined by the State Geologist (CDMG 1988). The active Whittier Fault Zone is located along the south ridge of Tonner Canyon, but no portion of the zone is within the City's present sphere of influence. Therefore, the potential for surface rupture within the City due to movement of the Whittier Fault is considered slight (CDMG 1980). In the adjacent Perris Block, the potentially active Chino Fault has also been identified near the City of Diamond Bar. It is generally located along the base on the Chino Hills, as defined by State Route 71. This regional fault joins with the Whittier Fault near the Prado Dom in Corona. Together, they proceed southeast as the Whittier -Elsinore Fault. At the closest point at which it has been accurately mapped, the Chino Fault is approximately five miles east of the eastern border of the City (EDAW 1982). However, if the inferred location of the fault is extended based on its existing location and alignment, lt could pass within one mile east of the Tres Hermanos area. Local Faults Diamond Bar is on the northern or 'upthrown' side of the Whittier Fault, which is broken by several localized faults. The Diamond Bar and Arnold Ranch Faults are located within the City boundaries. but are considered inactive faults (see Figure II -8-5). The last movement along these two faults was probably some time during the Miocene period (11-25 million years ago). In addition, these local faults have various folded strata (synclines and anticlines) associated with their structure. These folds create additional stress in the underlying bedrock formations and the overlying soil units, which further contributes to the unstable condition of local slopes (LACDRP 1982). g. Earthquake Measurement Scientists use two basic scales to measure earthquakes caused by faults. The first is the Richter Scale, which measures the magnitude (M) of energy released by an earthquake. The Richter Scale is a logarithmic scale such that an increase of 1.0 on the scale represents an increase of about 32 times the amount of energy released. Thus, an M 6.0 earthquake releases 32 times as much energy. as an M 5.0 event. This is the most commonly used scale to estimate the 'size" of earthquakes, as it is a measure of the total energy released by a particular event. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-7 The second scale used to measure earthquakes is the Modified Mercalli scale, which subjectively measures the observed and experienced effects of an earthquake at a particular location. This scale ranges from a low of I (not felt except by a few persons under especially favorable circumstances), to a high of XII (total damage with actual waves seen on the ground surface, lines of sight distorted, and objects thrown upward Into the air). Thus, an earthquake will have one Richter magnitude, but will have many different Mercalli intensities based on the effects and level of damage In different areas. Table II -13-1 provides a description of the Mercalil intensities while Table II -B-2 compares Richter magnitude to Mercalli Intensities. Based on their study of faults and earthquakes, scientists can estimate the largest earthquake that can be expected on a particular fault (maximum probable earthquake), as well as the greatest amount of groundshaking that could occur during such an event (maximum acceleration). Seismic Intensity Is a function of several factors, but the most important are the distance from the epicenter (the point of ground directly above the earthquake source) of the event, and the nature of the geologic materials through which the vibrations pass. Generally, the shock waves remain unchanged in bedrock, are amplified to a degree in thick alluvium, and are generally amplified in thin alluvium. The City of Diamond Bar is located in an area subject to low to moderate groundshaking (LADCE 1980). This results from its proximity to regional and local faults and the type of underlying soil materials. In the case of Diamond Bar, areas with thin alluvial soils underlying bedrock have the highest potential for groundshaking. Although the regionally active faults produce the largest magnitude earthquakes, the potentially active faults represent more significant earthquake threats in terms of groundshaking. According to the County engineer, the San Andreas is estimated to have a maximum potential earthquake of magnitude 8.3, which would produce a maximum ground acceleration of 0.16 gravity. However, two other active faults, Raymond Hills and Norwalk, are expected to produce slightly more groundshaking (0.17 gravity) than the San Andreas Fault. By comparison, all four of the potentially active faults could produce ground accelerations much greater than the active faults, even though their maximum earthquakes are smaller. This is because the potentially active faults are closer to Diamond Bar than the active faults. The Whittier fault is expected to produce the most groundshaking in Diamond Bar, on the order of 0.63 gravity for bedrock acceleration. h. Earthquakes Historically, Southern California has been seismically active. The San Andreas Fault is considered the most significant earthquake threat in California (in terms of overall magnitude), and has been the source of numerous significant earthquakes in the past. In 1857, an 8+ magnitude earthquake occurred at Fort Tejon near Los Angeles, and an 8+ earthquake almost destroyed San Francisco in 1906. Both of these events were caused by movement along the San Andreas Fault. Major events (M 8+) on this fault have a recurrence interval of 50-300 years with an average of 160 years between occurrences. Since the last major earthquake on the San Andreas was in San Francisco in 1906, we are well into the "window of opportunity" for another major earthquake on this fault. In addition, scientists have generally identified the portion of the fault in the Southern California region as having the most likelihood for a major event (CDMG 1982). Diamond Bar does not have an historic record of any earthquakes having an epicenter within the City limits or Its sphere of influence, and no significant movement has ever been recorded for any of the minor faults -traversing the City (LADCE 1980). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B -B SOURCE: \\F \ `\\ \\\\ SAN GASRIEL FAULT ZONE/ / t INDWN Hill FAUIj, .Rancho Cucamonga Whittier • r.. Brea %RWALK FAULT (M 6.d) Fullerton r Anoh l fl % NEWPORT-INGLEWOOD FAULT ZONE (M 7.4) RICHER MAGNITUDE FAULT LOCATION (APPROXIMATE) Planning Network, 1990. FIGURE II -B-4 LAN N I NG N EiV"X NORTH NOT TO SCALE �04r / Pomona Ontario Chino ,\ SAJN � ERNARDINO .� •�oUNTY � I t' I _Norco • RIVERSIDE '�OUNTY REGIONAL FAULTS DIAMOND RAR, m _ Z CL �Ct: _.,. QC9 Z O LLJ LLJ U 0 _ C UW oCZ5 Y m K C m o 0 m o < S m o m w 0 L Z o < ao�so 0 o -L) 2-g LL o zo r ON0 Table II -B-1 Modrted Mercallii Intensify Scale Merc oll Description of Effects Scale I Not felt except by a very few under, especially favorable circumstances. II Felt only by a few persons at rest, especially on upper floors of buildings. Delicately suspended objects may swing. III Felt quite noticeably indoors, especially on upper floors of buildings, but many people do not recognize it as an earthquake. Standing motor cars may rock slightly. Vibration, like the passing of a truck, occurs. Duration estimated. N During the day, felt indoors by many, outdoors by few. At night, some awakened. Dishes, windows, doors, disturbed; walls make cracking sound. Sensation like a heavy truck striking a building. Standing motor cars rocked noticeably. V Felt by nearly everyone, many awakened. Some dishes, windows, etc. broken; a few instances of cracked plaster; unstable objects overturned. Disturbances of trees, poles, and other tall objects sometimes noticed. Pendulum clocks may stop. VI Felt by all, many frightened and run outdoors. Some heavy furniture moved; a few instances of fallen plaster or damaged chimneys. Damage slight. VII Felt by all, everybody runs outdoors. Damage negligible in buildings of good design and construction; slight to moderate in well-built, ordinary structures; considerable in poorly -built or badly -designed structures; some chimneys broken. Noticed by persons driving motor cars. VIII Damage slight in specially designed structures; considerable in ordinary, substantial buildings, with partial collapse; great in poorly -built structures. Panel walls thrown out of frame structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned. Sand and mud ejected in small amounts. Changes in well water. Persons driving motor cars disturbed. DC Damage considerable in specially designed structures; well-designed frame structures thrown out of plumb; great in substantial buildings, with partial collapse. Buildings shifted off foundations. Ground cracked conspicuously. Underground pipes broken. X Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations; ground badly cracked; nails bent. Landslides considerable from river banks to steep slopes. Shifted sand and mud. Water splashed over banks. XI Few, if any (masonry) structures remain standing. Bridges destroyed. Broad fissures in ground. Underground pipelines completely out of service. Earth slumps and land slips in soft ground. Rails bent greatly. XII Damage total. Practically all works of construction are damaged greatly or destroyed. Waves seen on ground surface. Line of sight and level are distorted. Objects are thrown upward into the air. Source: 'Los Angeles County General Plan', 1988. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-1 1 Table U -B-2 Comparison of Richter Magnitude and Modified Mercalli Intensity Expected Modified MercalG Maximum Intensity Richter Magnitude T (at epicenter) 2 1 -II Usually detected only by instruments 3 III Felt indoors 4 N -V Felt by most people; slight damage 5 VI -VII Felt by all; many frightened and run outdoors; damage minor to moderate 6 VII -VIII Felt by all, everybody runs outdoors; damage moderate to major 7 IX -X Major damage 8+ X -XII Total and major damages Source: 'Callfornia Geology,' September 1984 1 After Charles F. Richter, 1958, Elementary Seismology CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-8.12 Table 11-8-3 Local Faults Max. Peak Distances Max. Probable Ground FaWVFau1F Zone (miles) Earthquake Acceleration Active Faults San Andreas Newport -Inglewood Raymond Hill San Fernando Norwalk Potentially Active Faults San Gabriel Sierra Madre Whittier San Jose 26.0 8.3 0.16 24.0 6.8 0.13 18.0 6.4 0.18 34.0 6.4 0.06 16.0 6.1 0.17 16.0 7.0 0.25 8.0 6.7 0.39 5.0 6.0 0.63 3.0 6.2 0.52 Source: los Angeles County Department of the County Engineer, 'Geologic -Seismic Study for the General Plan, Diamond Bar', Engineering Geology, Environmental Development Division, September 1980. 1 Closest distance to the fault from the Intersection of the 57 and 60 freeways. 2 Maximum earthquake magnitude at the epicenter, as measured on the Richter scale, which Is likely to occur within the Ute of proposed structures (50-100 years) on a given fault. 3 Horizontal peak acceleration created in Diamond Bar compared to vertical force of gravity (1.0) expected in Diamond Bar. Average peak accelerations calculated from repeatable high maximum bedrock accelerations, calculated by reducing average peak accelerations by a third for faults less than 20 miles away. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -B-13 Primary Seismic Hazards The primary seismic hazards associated with earthquakes are ground rupture and groundshaking. Ground rupture, such as seismic fissures, refers to displacement of the ground along a fault which can occur during strong earthquakes. The extent of rupture depends on the specific soil conditions and the severity of a particular seismic event. Such displacement may be vertical, horizontal, or both, and can be up to 20 feet or more in a major earthquake. Utilities, roads, and other linear features are particularly vulnerable to damage as a result of ground rupture where they cross faults. The California Division of Mines and Geology analyzed potential major seismic activity in Southern California in a special report in 1982, and found that the possibility of actual ground rupture in Diamond Bar was low. By for the most widespread effect and the greatest cause of damage in an earthquake is grouncshaking. The Intensity of this shaking depends on several factors, including the magnitude of the earthquake, distance from the earthquake epicenter (point of the earth directly above the focus of the earthquake), and underlying soil conditions. In general, the larger the magnitude of an earthquake and the closer a site is to the epicenter of the event, the greater will be the effects. However, soil conditions can also amplify earthquake shock waves. Generally, the shock waves remain unchanged In bedrock, are amplified to a degree in thick alluvium, and are greatly amplified in thin alluvium. The thicker sediments of the alluvial valleys and fans within the City and sphere of Influence are located in the central and southern drainage channels and basins, most notably the Brea Canyon, Diamond Bar Creek (channeq, and Tanner Canyon. The thinner alluvium and exposed bedrock areas are found in the hills southwest, southeast, eastern, and northern portions of the City (LADCE 1980). In addition, County data shows that ridgelines within the Puente Formation experience higher groundshaking compared to hillside or valley locations. The City its included in two of the three seismic shaking zones as determined by the County of Los Angeles. These zones are determined by three factors: distance from active faults; the maximum earthquake that can be expected on each fault; and the underlying soil conditions. Zone 2, referred to as a Medium Relative Ground Response zone (RGRm), represents areas that would be exposed to a moderate level of seismic shaking. Zone 1, or the Low Relative Ground Response (RGRO zone, would be exposed to a relatively low intensity of groundshaking. Zone 3, or the High Relative Ground Response (RGRh) zone, is not located within the present limits of the City or the sphere of influence (LADCE 1980). The locations of these zones in the Diamond Bar area are shown in Figure ll -B-5. Zone 2 could theoretically experience earthquake producing ground accelerations in bedrock exceeding .50 4 ("g' represents the force of gravity), and Zone 1 between .40 g and 50 g. Corresponding Modified Mercalli intensities would be roughly IX to X for Zone 2, and VIII to IX for Zone 1. tt Is important to 'note that these are maximum values anticipated for the maximum credible earthquake. Their probability of occurrence must be evaluated, along with the site conditions and intended land usage, before values can be used for design or construction purposes. If a major earthquake were to occur, damage could be greater for stiff, relatively inflexible structures in low response areas (Zone 1), while tall structures in medium response areas (Zone 2) would also experience damage. The potential for damage is greatest, regardless of the shaking zone, to unreinforced masonry and frame structures not secured to with their foundations, as well as to poorly built structures. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-14 Secondary Seismic Hazards In addition to primary hazards, groundshaking can Induce several kinds of secondary seismic hazards depending on the type of local soil conditions present. Secondary seismic hazards Include liquefaction, differential settlement. landslides, and seiching (Los Angeles County General Plan, 1988). In addition, groundshaking may also induce the threat of fire by damaging or destroying natural gas or electrical utility lines. The location of secondary seismic hazards are shown in Figure II -B -S. Liquefaction The greatest danger from liquefaction occurs in areas where the ground water table Is within thirty five (35) feet of ground level and the soil is poorly consolidated or relatively Y_uncompocted. This condition is characterized by the sudden loss of shearing resistance due to ground shaking combined with an increase in pore wafer pressure. Subsequently, this will often result in the collapse or displacement of building foundations. Identification of liquefaction zones is based primarily on the occurrence of groundwater In surficial alluvial deposits. Water in the east San Gabriel Valley is generally found at depths of 30 to 200 feet at present, although the Los Angeles County General Plan did identify areas along the San Jose Creek, adjacent to the City, as having groundwater within 30 feet of the surface (LADRP 1988). Areas of high groundwater have also been previously documented within Diamond Bar (LACDRP 1982 p. 35). The EIR for the Community Plan prepared in 1982 indicated that water levels as high as 14 to 35 feet below the ground surface have occurred in Diamond Bar. These areas have historically been in Brea, Diamond Bar, and Tonner canyons. The regional water table is probably lower than historic levels, due to the overuse of groundwater in the East San Gabriel Valley. However, the potential for liquefaction may still exist along the stream channels in Diamond Bar. This is because the City does not use local groundwater (Walnut Valley Water District 1990), although local wells are used by residents of "The Country" development. Differential Settlement The moderately thick alluvial soils which underlie some of the City could be subject to differential settlement during intense seismic shaking, especially where several fill materials have been used that have different settling rates. This type of seismic hazard results primarily in the damage to property when an area settles to different degrees over a relatively short distance. The actual potential for settlement is, however, difficult to predict. Landslides Most of the hillsides in Diamond Bar have moderate to high potential for landslides. The stability of a slope is attributed to such factors as the soil type, gradient of the slope (greater than 25 percent particularly), underlying geologic structure, and local drainage patterns. The rolling topography and composition of local soils throughout most of the City create numerous areas for potential landslide hazards. Although many historic landslide locations have since been stabilized through proper grading and development, there still exist a number of potential landslide areas along the eastern third of the City as well as in Tonner Canyon (sphere of influence). Figure II -B-5 shows the location of landslides identified by the Los Angeles County Engineer (1980). Seiching This phenomenon occurs when seismic groundshaking induces standing waves (seiches) inside of water retention facilities, such as reservoirs and water tanks. Such waves can cause the retention structures to fail and flood downstream properties. Seiching may be a potential hazard for areas in proximity to the various reservoirs in the City. Explosion/Fire/Damage Significant groundshaking could cause explosions or fires in residential or non-residential areas by breaking natural gas and electrical lines. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-15 Mineral Resources As a part of the Surface Mining and Reclamation Act (SMARA), the California Department of Conservation is responsible for evaluating and designating potential mineral resource areas within the State. In its Special Report #143, the Department of Mines and Geology classified sand and gravel (construction -grade aggregate) resources within the greater Los Angeles area (CDMG 1987 Part Vlj. The City of Diamond Bar is located in the southwest corner of the Claremont -Upland Production -Consumption (P -C) Region (this term refers to the production and consumption of aggregate materials for building). This area is most known for its extensive aggregate deposits in the south -facing alluvial fans of the San Gabriel Mountains, such as Son Antonio and Cucamonga Creeks. The State estimates that this P -C area will require 245 million tons of aggregate to meet local demands through the year 2031, while the current reserves equal only 55 million tons. The report focuses on urban development pressures on the remaining washes in the foothill area that are not currently producing (San Dimas,. Day, and Deer creeks). Based on the level of Information available, the State further classifies each P -C Region into the following four (4) Mineral Resource Zones (MRZs), depending on the amount and type of resources: • MRZ-1 'Areas where adequate information indicates that no significant mineral deposits are present, or where it is judged that little likelihood exists for their presence.' • MRZ-2 "Areas where adequate information indicates that significant mineral deposits are present, or there is a high likelihood for their presence.' • MRZ-3 'These areas incorporate land containing mineral deposits, the significance of which cannot be evaluated from available data." • MRZ-4 "Areas where available information is inadequate for any other classification." The land within Diamond Bar and its sphere of influence are characterized as only MRZ-1 and MRZ-3 (CDMG 1987). The only areas that could contain significant aggregate resources (MRZ-3) would be within the Soquel member of the Puente Formation, which are shown in Figure II -8-2. According to the Division of Mines and Geology, this formation... "consists of poorly cemented and pebbly sandstone, interbedded siltstone, and local lenses of pebble conglomerates. The MRZ-3 classification was mainly given to areas underlain by these sediments based on lithologic descriptions and field observations. In the past, aggregate was produced from a conglomerate lense of the Soquel Member in an area east of EI Toro Marine Air Station, located in the adjacent Orange County-Temescal Valley P -C Region. It is not known whether conglomeratic lenses of the Soquel Member within the San Jose and Puente hills have similar physical and chemical properties to those mined in the east EI Toro area' (CDMG 1987). However, the report also indicates that "siltstones of the Puente Formation are generally unsuitable for use as aggregate" (CDMG 1987). The remainder of the City and sphere of influence is classified as MRZ-1 with no significant mineral resources. Over 95 percent of the potential aggregate Teserves for this P -C Region is projected to come from the alluvial fans in the San Gabriel foothills. Thus, the Diamond -Sac area would need to import aggregate material even if a minor local source was discovered and exploited. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-17 2. ISSUES AND OPK)MN TIES The primary earth resource issue facing the City Is to what degree seismic safety and soil stability should play In preserving or otherwise protecting locally significant landforms. This question is more directly related to the overall question of preserving (or not preserving) prominent landforms that remain In the City. The Landforms and Topography section (II -A) of this report identified natural landforms or slopes in the City that should be given special consideration when planning for future land uses. Some of these areas also have building limitations because of local soil conditions or potential changes during earthquakes (landslides or liquefaction, for example). However, most of these limitations can be overcome with some degree of engineering and careful construction, depending on the condition. Therefore, other considerations, such as the extent of hillside modification through grading, or the amount of natural hillsides and vegetation that will be preserved, will probably weigh more heavily in the Issue of hillside changes. a. Geology/Seismicity The principal fault most likely to produce earthquake damage in or near the City is the Whiffler Fault, although a major temblor on either the San Andreas or Newport -Inglewood fault would have - serious impacts on the entire region. The Whittier Fault Zone, as delineated by the Department of Mines and Geology for the Alquist-Priolo Act, is considered an active fault. Policies and criteria for dealing with seismic hazards were established to assist cities and counties, although the act does not preclude local governments from adopting more stringent requirements (CDMG 1982). New development within the City should be built to withstand the likely maximum amount of groundshaking anticipated in the area without loss of life. b. Unreinforced Masonry The 1933 long Beach earthquake led to the first State and local laws requiring seismic resistance building designs. Buildings constructed prior to 1933 may offer little or no structural protection in a major earthquake. The Uniform Building Code, a set of structural requirements for building construction and safety, did not require until 1952 that single family homes be bolted to their foundations. Other than unreinforced masonry structures, the only buildings covered by retroactive laws are public schools. The State has regulated school safety requirements since the Field Act was adopted after the 1933 Long Beach earthquake (Title 24, State Building Standards Commission, 1987). Although buildings constructed offer 1933 offer a somewhat greater degree of earthquake resistance, it was not until after the 1971 San Fernando earthquake that building code requirements became even more stringent. The building code was changed to require positive anchorage of wall panels to floor and roof diaphragms. These requirements, however, are not retroactive to existing buildings. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .lune 8, 1992 II -B-18 B is possible that one of the most serious seismic hazards in the City could be the presence of unreinforced masonry buildings. Although nearly all buildings in the City were built subsequent to the 1952 Building Code, there may be some buildings In the City that are not properly built, or have fallen Into such disrepair, that they would not be safe in a major earthquake. Unreinforced buildings may be subject to collapse or substantial destruction during a moderate to severe earthquake. The Unreinforced Masonry Building Act (1986) requires cities and counties to prepare on "Inventory and Mitigation Plan" for all such buildings within their jurisdiction. It should be noted that according to the State Historical Preservation Commission, buildings that are designated as having local historical significance are exempt from standard seismic upgrade requirements. C. Soils/Slope Stability Due to the many limitations of local soils and their underlying geology, the City may wish to have specific geotechnical and soils reports prepared for each new development. This would especially apply to the Tres Hermanos area, where previous County data on soil limitations Is lacking. Figure II -B-5 delineates the known geologic and seismic hazards that could affect undeveloped areas of the City. Areas that could be subject to liquefaction should have adequate testing and reports prepared to assure that this will not affect the proposed development. In general, it is advisable not to develop land with slopes greater than 25 percent without significant hillside design review (Los Angeles County General Plan, 1980). Hillsides with slopes of 10-25 percent, or slopes that contain soils or underlying formations that produce severe building constraints, require engineering studies to be performed to determine the most appropriate structural design. Older structures need to be upgraded if they are to withstand a major earthquake, while new developments must conform to applicable seismic codes. It is recommended that the local grading ordinance address such issues as overwatering of slopes, improper placement of fill, poor soil compaction, and inadequate hillside grading. This will ensure the stability of the remaining hillsides that are developed. Local landslides should be stabilized prior to development, and local soil materials used carefully for fill material, especially those containing clay or other limiting material. To minimize the potential for differential settling, the use of more than one source or type of fill material for a particular project should be minimized, or carefully controlled, to avoid vastly different materials being in contact with each other. Expansive soils should not be allowed, or used carefully to assure that soil creep or expansion does not occur. The City may wish to discourage or prohibit the use of septic tanks, leach fields, etc., especially in areas with soil constraints. This limitation should be considered not only in the immediate area containing limiting soils, but also in areas downslope since leachates can flow underground and saturate non -project soils. This could contribute to differential settling or soil expansion it were to encounter soil materials susceptible to such conditions. d. Sphere of Influence The City should carefully consider development in the sphere of influence in light of seismic limitations. Low density or open space uses would be appropriate. Overall access to the sphere area must also be an important consideration, especially if a major earthquake were to cut off primary access. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1 M II -B-19 G. Mineral Resources The mining of aggregate materials within the City limits or sphere of influence of Diamond Bar would not be economical or practical for the following reasons: • A review of historical and recent geotechnical reports from local development projects indicates that lenses or other structures do not bear aggregate materials In deep formations, therefore, substantial land area would have to be disturbed to mine sufficient aggregate materials (see Report by the Los Angeles County, Department of the County Engineer, 'G eologic•Seismic Study for the General Plan, Diamond Bar', 1980); • There is an insufficient amount of undeveloped land available that contains the Soquel member of the Puente Formation to warrant economical removal; • The steep terrain of available areas would make access and removal difficult and expensive; • Mining of undeveloped areas would be incompatible with nearby suburban development; and • Mining would have to take place on undeveloped slopes, many of which contain the last remaining natural vegetation within the City. In addition, the mining of aggregate materials within Tonner Canyon (sphere of influence) would not be economical or sensitive to the unique environment of the area. Such activity would seriously harm the riparian habitat that exists there, and more than likely degrade its water quality and noise environment, to the detriment of local native species that now inhabit the canyon. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -B-20 C. DRAINAGE AND FLOOD CONTROL 1. ExLsnNG SETTING a. Drainage Basins The varied topography of Diamond Bar creates complex drainage patterns through a number of local watercourses. Seasonal runoff from the City of Diamond Bar and its sphere of influence flow into Los Angeles County to the west and Orange County to the south, with a minor amount going into San Bernardino County (Chino Basin) to the east. Diamond Bar Creek and Sunset Crossing Flood Control Channel convey runoff from the northern and western half the City. This runoff travels west toward San Jose Creek, where it is eventually conveyed to the los Angeles Basin. The southern and eastern half o1 the City is drained by the creeks running through Brea Canyon and Tonner Canyon, which carry water southwest to the Orange County Basin. A small portion of the northeast corner of the City drains towards the east Into the Chino Creek Basin (which also reaches the Orange County Basin via the Santa Ana River). All of the runoff water from Diamond Bar eventually reach the Pacific Ocean. The following summarizes the major drainage basins and channels in the City and sphere of influence. Figure II -C-1 shows their locations. San Jose Creek This is a fully improved, regional flood control facility maintained by the Los Angeles County Flood Control District. it collects runoff from most of the east San Gabriel Valley and conveys it into the Los Angeles Basin. It is fed by two local drainage channels: Diamond Bar Creek and the Sunset Crossing Flood Control Channel. Together, these channels drain approximately 45 percent of the City of Diamond Bar. Diamond Bar Creek This channel enters Diamond Bar near the southern intersection of the 57 and 60 freeways, and travels along the west side of the dual freeway until it reaches the Diamond Bar Golf Course near Grand Avenue. Here it posses under the roadway and drains the small lake on the north side of Grand within the golf course. The unimproved channel collects runoff from the lands generally north of Grand Avenue between the 57/60 freeways and the eastern ridgeline of the City. It also drains the following areas: • Existing residential areas northeast of the 60 Freeway and Golden Springs Drive (northwest and north of Reagan Park), • The corporate center on Golden Springs Drive southwest of Grand Avenue, • The existing mixed use areas west of the 57 Freeway, both south and north of the 60 Freeway within the City limits, and • The east -facing rolling hills within the City of Industry on the west side of the 60 Freeway. Diamond Bar Creek is all or partially improved in some locations, such as west of the 60 Freeway (refer to Flooding, below), while in other locations, such as near the Diamond Bar Golf Course, it is unimproved. This channel drains over a third (38 percent) of the City of Diamond Bar, and represents the largest local basin. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -C-1 Sunset Crossing Flood Control Channel This channel is improved as a rectangular concrete channel from the 57 Freeway west to the end of the residential area along Sunset Crossing. From here, the channel is unimproved to Son Jose Creek. This channel collects runoff from the residential areas north of the 60 Freeway and west of Golden Springs Drive, along with runoff from both sides of Sunset Crossing, west of the 57 Freeway, and conveys it into the south fork of the San Jose Creek as 6 passes southwest within the cities of Walnut and Industry. This facility drains approximately 7 percent of the City's land area. Brea Canyon Channel This creek collects runoff from the developments and slopes along Diamond Bar Boulevard south of Grand Avenue, and conveys it to the southwest towards Orange County. While improved and undergrounded within the developed portions of the City, Brea Canyon Channel becomes an unimproved channel south of Diamond Bar Boulevard and the 57 Freeway. It then follows the historical alignment of Brea Canyon Road. It also drains the areas west of the 57 Freeway south of Pathfinder Road, and all of the canyons on the "front" (northwest -facing) side of "The Country" development. This creek drains approximately 28 percent of the City of Diamond Bar, and is its second largest local drainage basin. Chino Creek Approximately 5 percent of the City, in the extreme northeast, undeveloped corner of the Tres Hermanos area, drains east toward Chino Creek in the Chino Basin. Runoff from this area eventually reaches Orange County via the Santa Ana River. Toner Canyon Creek Just under a quarter of the City of Diamond Bar is drained by the creek flowing through Tanner Canyon. The middle and upper reaches of this natural canyon are located east of the City, although the upper reaches are within the Tres Hermanos area of the City. In addition, much of the middle and lower sections of the canyon are within the City's sphere of influence (the portion north of the Orange/Los Angeles County line). All of the canyons on the "back" (southeast -facing) side of "The Country" development drain into Tanner Canyon. This channel drains almost a quarter (22 percent) of the City area and two thirds (65 percent) of Tanner Canyon. Flows collected in the canyon meet with Brea Canyon (creek) at the 57 Freeway and travel south into Orange County. The canyon is also drained by Lions Canyon and Sonome Canyon, two smaller creeks that flow southeast and south, respectively, off of the high ridge along the south side of Tanner Canyon. Runoff from these canyons eventually enter Carbon Canyon Creek in Brea to the south. These two creeks drain approximately the southeastern third (35 percent) of Tanner Canyon. b. Flooding At present, there are no major flooding problems identified within the City limits of Diamond Bar (Koss 1990, FDS 1988, FEMA 1980). According to the Federal Emergency Management Agency (FEMA), the Flood Insurance Rate (FIRM) Map for Diamond Bar shows that essentially all of the lands within the City limits are within flood zone "C", which means "areas of minimal flooding" (FEMA 1980). However, there are two areas within the City or sphere of influence that have identified flood hazards according to the FEMA study: CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -C-2 Reed Canyon Chanel One small section of Diamond Bar Creek, at the intersection of Old Brea Canyon Road, just north of the 60 Freeway, was identified by the FIRM study as having a slight flooding potential. This portion of the creek Is referred to as the Reed Canyon Channel. A small area Immediately upstream Gust east) of the roadway is classified as flood zone 'A', which means that it is an area of 100 -year flooding, but no base flood elevations or flood hazard factors have been determined. A slightly larger area downstream Gust west) of Brea Canyon has a flood zone designation of "AO", which means areas of shallow flooding during a 100 -year flood, where depths are between one (1) and three (3) feet. Average depths of inundation are shown (on the FIRM map), but no specific flood assessment has been made (FEMA 1980). Figure II -C-2 shows the location of these flood zones. Toner Canyon A portion of lower Tonner Canyon has been assigned a flood designation of 'K by FEMA because It is subject to 100 -year flooding. However, no base flood elevations or specific flood hazards have been determined. In addition, the FIRM study only addressed canyon flooding up to one mile north of the Orange/Los Angeles County line, and no additional studies have been done. It is therefore possible that additional flooding potential exists within Tonner Canyon that has not been identified as yet. Figure II -C-2 shows the location and extent of the presently determined flood hazards in the canyon. There are two houses and a maintenance building along this portion of the canyon, but they are on graded benches substantially above anticipated flood levels. The flood plain of the San Jose Creek is also adjacent to the City of Diamond Bar in two locations: near Old Brea Canyon Road north of this 60 Find north of Sunset Crossing and the 57 Freeway. Much of the land is these areas is adjacent to the eastern bank of the creek, and is planned for industrial uses. The FEMA study classified these areas as flood zone 'D', meaning "areas of undetermined, but possible, flood hazards" (FEMA 1980). While some of these areas have been developed since the 1980 FEMA study, large tracts remain vacant, and could experience flooding during a 100 -year event. The extent of this flood zone, relative to the Diamond Bar city limits, is shown in Figure II -C-3. C. Flood Control Facilities Existing flood control programs and facilities, for the region as well as within the City of Diamond Bar, have been built by the Los Angeles County Department of Public Works (Anderson 1990). The Present system consists of a series of natural channels, storm drains, and improved channels designed to convey runoff in an efficient and safe manner. There are no regional flood control facilities planned within the City, nor are any needed according to the County (LADPW 1985). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -C-3 C O z 0 u _F Z9 0z U� OomU' u0 O" Y Z Q � z J Z U O; mo m �0� U U nZ 3 3 -U Z U ;o W pr u W 30 O oc J O- N ri v vi o ,� m m o W R CD C O z 0 u _F Z9 0z U� OomU' u0 O" Y z Z U O; mo m �0� U U nZ 3 3 -U Z U ;o W pr u n -0 30 O oc J O- N ri v vi o ,� m m o Z R P� 0 C O z 0 u _F Z9 0z U� OomU' u0 O" u 0 0 Z /'iCL}f )) i|} !}}) , . }JI( �� IM _`(77 cn �} LU z � 10\} 0 4 § y c V— §_ � 2/!{$ * •— q q § § ( �\ k� 'a LL. u 0 0 CL 0 < 0 LU z LLJ 0 z a The local drainage system Is largely complete within the City of Diamond Bar, with only a few projects left to complete the backbone system (Koss 1990). The San Jose Creek represents the major regional collector for runoff for the region. it is a fully improved, trapezoidal concrete channel which transfers storm flows from the east San Gabriel Valley, including much of the urbanized portions of Diamond Bar, into the Los Angeles Basin. At present, no major improved flood control structures serve Tonner or Brea canyons. In most of the upland areas of the City, runoff is first collected by streets and curbs, and then directed toward existing County drainage control structures, as shown in Figure 11-C-4. In natural areas, drainage that flows toward the west is generally intercepted by a roadway, where it is then diverted towards a flood control facility. The County system has been designed and installed to collect and transport flood flows that would be produced by development at the density of the Los Angeles _County General Plan. While the City General Plan may modify the overall densities or locations of land uses, it is likely that the total amount of land coverage, and thus the amount of runoff generated, will be similar to those levels used to design and build the existing flood control system. Therefore, no significant upgrading or changes should be required to existing or planned drainage facilities within the City (Koss 1990). There are, however, a number of locations within the City with existing deficiencies or needs identified for additional flood protection, as shown in Figure II -C-4. These proposed improvements are based on the most recent assessments by the Los Angeles County Department of Public Works (Koss 1990, LACDPW 1985). Although these are identified projects according to County Public Works (Koss 1990), all flood control projects are scheduled for funding on a County -wide basis as funds are available, so there is no way at this time to ascertain when or which projects will actually be constructed In the future (Anderson 1990). d. System Deficiencies The Los Angeles Department of Public Works has identified 16 deficiencies, needs, or planned improvements in the Diamond Bar area, as shown in their 1985 "Plan for Flood Control and Water Conservation' (LACDPW 1985). The following discussion of flood control needs or deficiencies is organized by local drainage basins: • Diamond Bar Creek Much of the Upper Sycamore Canyon area east of Diamond Bar Boulevard, north of Grand Avenue is undeveloped, but a number of the ridges north of Grand Avenue have been developed recently into homes. The Los Angeles Department of Public Works believes that this construction may have contributed large amounts of sediment that have periodically blocked the steel culverts that convey runoff under Golden Springs Drive to the retention basin (lake) on Diamond Bar Golf Course (Koss 1990). The County is now in the process of removing the sediment from these structures, but this is a long-term maintenance problem that could continue as additional development within this drainage basin occurs each year. Diamond Bar Creek contains the only identified potential flood heard within the City (see previous section on Flooding). The Los Angeles County Department of Public Works has identified the following seven system deficiencies or flood control needs within this drainage basin (X.XX refers to County Public Works numbers for each project, as shown in Figure II -C-4). A number of these improvements are transfers of responsibility from some other municipal agency to County Public Works, and are designated in this text and on Figure II -C-4 as Municipal Transfer Drain (MTD), while Public Drains are abbreviated PD. It should be noted that the following list of proposed improvements is only current as of 1985, and some of the improvements, especially in the industrial areas, may hove already been installed wholly or in part. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -C-7 The six flood control needs or projects identified by the County to address drainage needs for the Diamond Bar Creek drainage area are: 2.01 An additional 1,800 feet of storm drain to augment Public Drain 1469, to serve Old Brea Canyon Road just south of Colima. 3.07 A 1,000 foot portion of a 4,150 foot long channel and/or drain mainly designed to connect developing industrial parcels within the City of Industry to San Jose Creek. 3.16 Approximately 7,000 feet (1.3 miles) of storm drain and/or channel to serve Lycoming east of Old Brea Canyon Road. This Is part of another project (3.17) designed to serve this portion of Diamond Bar along with the City of Industry areas north of the Union Pacific railroad tracks by eventually hooking project 3.16 up with the San Jose Creek. 3.17 Planned for 2,000 feet of additional storm drain to connect projects 3.16 and 3.32 to San Jose Creek. 3.32 Approximately 1,500 feet of storm drain designed to provide service to development on Lemon Avenue, south of the railroad tracks in Diamond Bar, by connecting into projects 3.16 and 3.17. 3.33 Actually within the City of Industry, this 750 foot long storm drain is needed to serve the business areas in Diamond Bar located southeast of Old Brea Canyon Rood and Washington (portions of this improvement may already be constructed). • Sunset Crossing Flood Control Channel Due to its age and location, there is very little setback between this facility and a number of homes that front onto the southwest side of Sunset Crossing. The Los Angeles County Department of Public Works indicated no major problems with this facility other than periodic maintenance. However, the County has identified the following four needs or projects for this drainage area: 3.27 This project would improve the existing Sunset Crossing flood control channel and extend it 1,100 feet west to connect Public Drain 389 with the South San Jose Creek. 4.05 Short section of storm drain to connect development with existing drainage structures along Palomino to Sunset Crossing facilities, which in turn will drain to San Jose Creek (see project 3.27). 4.31 This project would extend Public Drain 863 1,500 feet north to serve the land south of Highland Valley Road. 4.32 This new section of storm drain will extend 3,000 feet up Golden Springs Drive, north of the 60 Freeway, to serve planned development (some or all of this improvement may already be installed). A new debris basin is also planned as part of this project on the south side of the freeway, to connect to Public Drain 268. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -C-8 Brea Canyon Channel The Los Angeles County Department of Public Works indicates no major maintenance problems for this channel other than periodic cleaning and desilting in the unimproved portions south of the City (Koss 1990). The County shows the following four drainage needs or improvements planned for this area: 2.05 Improvements to Brea Canyon Channel, connecting Public Drain 493 and 418 upstream with private facilities downstream. 2.06 Improvements to Brea Canyon Channel, connecting private system upstream with private facilities downstream. This improvement is actually outside (downstream) of the City limits but is adjacent to the sphere of influence. 2.07 This is an almost one -mile long improvement to the existing Brea Canyon Channel south of Grand Avenue, between Mt. Laurel Way and Morning Canyon Road. It should be noted that some or all of this project may have been completed already. 2.08 A short section of storm drain to connect Public Drain 984 with Public Drain 346 and Brea Canyon Channel. Chino Basin Several municipal drains have already been constructed east of Phillips Ranch Road, immediately north of the 60 Freeway (LACDPW 1985). Two of these drains, MTD 435 and MTD 442, will eventually be built to accommodate development in the northeast portion of the Tres Hermanos property. These projects represent over a mile of new storm drain, but some portions may already be built or in the planning stages. Toner Canyon (Sphere of Influence) This canyon has been maintained in close to a natural state, with no significant improvements to the stream bed. Oil drilling activities near the mouth of the canyon (at the 57 Freeway) and the Firestone Boy Scout Ranch in the middle portion of the canyon are the only intrusions into this wild area. The only maintenance performed on the creek channel are infrequent weed abatement by the California Department of Fish and Game, and natural flood flows. As of 1985, there were no flood control improvements planned within Tonner Canyon itself that have been identified by the Los Angeles County Department of Public Works (LACDPW 1985). e. Facilities Financing In the past, flood control improvements throughout Los Angeles County have been funded by four 250 million dollar general obligation bonds that were passed in the 1950s and 1960s. These funds were sufficient to provide a backbone drainage system in Diamond Bar, as shown in Figure II -C-4. At present, completion of this system is being financed through a "flood control benefit assessment district", which levies an assessment on each property owner to pay for additional construction. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -C-9 v \ § Z _ \ U z CL )R $!\ Ll -70 [@ -! ZOf LLJZ \)}� /\ LLJ . � so / \ § )R $!\ Ll -70 [@ -! /6 \)}� /\ O so R 0 � � � \ /KI § � New development Is required to "pay its own way", leaving the County to concentrate on providing connections to existing service and solve localized problems or deficiencies. Although the County Public Works Department has identified 16 needs or deficiencies within Diamond Bar, there is no multi-year capital Improvement budget to indicate which Improvements will be made in what years. The County presently schedules projects on a County -wide basis depending on available funds and the relative need for a particular project (Anderson 1990, Koss 1990). At present, there are 1,600 flood control projects left to complete the backbone system, including the 16 projects identified in Diamond Bar. These projects presently compete for the some (limited) funds. Other than the County's "Plan for Flood Control and Water Conservation" prepared in 1985, there is no master plan for flood control facilities in Diamond Bar that addresses funding and scheduling _ of specific projects (Istic 1990). f. Stormwater/Urban Discharge Permit Under new federal regulations Issued by the U.S. Environmental Protection Agency, jurisdictions are now required to obtain National Pollutant Discharge Elimination System permits in order to improve the quality of stormwater and urban discharge. The permitting authority in California is under the individual Regional Water Quality Control Boards, in this case, the Santa Ana region. A large portion of Los Angeles County has applied for and received such a permit; the County of Los Angeles is the lead, with a number of cities in the county, including Diamond Bar, as co -permittees. The role of Los Angeles County is that of coordinator, as well as being responsible for basinwide monitoring and for the stormdrains in unincorporated areas. The individual cities are responsible for implementing the permit requirements in their respective jurisdictions, and developing specific strategies (Best Management Practices") that will improve the quality of urban discharge into stormdroins. The City of Diamond Bar is considered a Phase II city on this permit, and thus will begin implementing the permit requirements commencing on July 1, 1992. Therefore, specific programs and strategies for the City have not yet been developed. Regardless, the programs and strategies developed and Implemented by the City will be consistent with the requirements of the permit overall. Implementation of flood control requirements as contained in this permit may have budgetary implications for the City. 2. ISSUES AND OPPORTUNITIES _ Without a master plan of drainage, it is difficult to determine if the City-wide drainage system, both existing and proposed, will be adequate to accommodate buildout of the City. However, most of the planned system is already installed, with 16 additional projects to be completed by the County in the future. Since there are no major drainage hazards or identified needs, it is likely that the existing system will be adequate. Although a master drainage plan may be unnecessary at this point, the proposed system should be reviewed by qualified engineering personnel to assure that all new and planned development can be adequately served. As part of an overall assessment of .drainage, the City may wish to prioritize flood control improvements, as presently planned by the County, or identify additional projects. The Los Angeles County Department of Public Works has indicated it will review any additions or corrections to their list of needs, deficiencies, or projects based on studies submitted by local agencies (Koss 1990). The City may also wish to inventory any areas of ponding, unusual surface erosion, etc., that might indicate potential drainage problems. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .kine 6, 1992 II -C-1 1 The City may wish to coordinate planned flood control improvements with the City of Industry serving the areas north of the 57/60 freeway interchange. Drainage facilities along Diamond Bar Creek where It passes under Old Brea Canyon Road (Reed Canyon Channel) should be examined to determine how to best alleviate potential flooding problems that might still exist at this location. The City should carefully examine development proposed in the Tres Hermanos area, as runoff from this area could contribute to continued blockage of drainage structures into Brea Canyon channel at the Diamond Bar Golf Course, for example. Development In the sphere of influence should alleviate existing flooding conditions, plus plan a comprehensive drainage that adequately controls runoff. The City may wish to encourage a joint flooding and flood control study for Tonner Canyon which could include, but would not be limited to, the following agencies or organizations: • U.S. Fish and Wildlife Service • California Department of Fish and Game • County of Los Angeles Public Works • County of Orange Public Works • Community of Chino Hills • Developer(s) of the Tres Hermanos - property • Southern California Golf Association • Boy Scouts of America • Union Oil • Brea Canyon Oil Company • The Country Homeowner's Association • Other land owners in the canyon CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-C-12 D. BIOLOGICAL RESOURCES 1. ExsnNG SETTING a. Flora The Diamond Bar area is considered an Intercostal environment because it is located between the Pacific Ocean and the foothills of the San Gabriel Mountains. The City encompasses a variety of roiling hills and steep canyons within the Puente and Chino hills. The Pacific Ocean and the nearby mountains provide the dominant climatic and physical constraints on the region. This area supports a variety of coastal and mountain vegetation types, which directly influences the kinds of plants and wildlife present.7 The height and location of the San Gabriel Mountains cause much of the available precipitation from weather systems to fall within the los Angeles basin and the San Gabriel foothills. The City and its sphere of influence contain five major native plant communities plus areas disturbed by human activity. Plant associations are most often defined by the dominant or most prevalent species. The area supports a variety of coastal and inland sage scrub, oak grasslands, walnut woodlands, several types of chaparral, and riparian or stream -side areas. There are also a variety of developed or otherwise disturbed areas that support landscape or weedy plant species. Annual grasses cover many of these disturbed areas, and have also invaded Into areas with native vegetation. There are several steep hillsides and canyons in the City that support isolated pockets of native vegetation. Table II -D-1 provides a list of plant species generally expected within the City and its sphere of influence. This table was compiled from the most recent local environmental documents. Standard taxonomic references were used for plants (Munz 1974), mammals (Janeson 1988), reptiles, amphibians (Stebbins 1985), and birds (AOLI 1982 and Robbins 1986). Sage Scrub This association comprises a variety of low to moderate height herbaceous plants, and is found on lower, undisturbed slopes. it is dominated by Sagebrush (Artemisia tridentata), White sage (Salvia apiana), Buckwheat (Erogonium spp.), and Rabbit brush (Chrysothamnus spp.). Many of its plants form the understories of other local plant associations, but it is not adapted to periodic fire (see Chaparraq. Chaparral This association occupies the higher, undisturbed slopes and is dominated by Chamise (Adenostoma fasciculatum) as well as other herbaceous coastal sage species such as White sage (Salvia apiana), and Buckwheat (Eriogonum spp.). Some hearty scrubs may also be present, such as Ceanothus (Ceanothus spp.), toyon (Heteromeles arbutifolia), Lemonade berry (Rhus laurinia), and scrub oak (Quercus dumosa). It can vary in "coverage" or "density" from very open to impenetrable, and it can be classified by the amount of herbs to scrub as either "soft" (mostly herbaceous) to "hard" (mostly scrubby or woody). Many chaparral plants have adapted to periodic wildfires to the point that some of the hard (woody) species actually depend on brushfires for the germination of their seeds, or resprouting of shrubs. This plant community requires fire to maintain its health, and can become seriously overgrown if not exposed to fire for long periods of time (over 15 years). Oak Woodland Also called oak grasslands, this dry, upland plant community occupies many rolling hills in the City, especially in Tonner Canyon. These hillsides support large, coast live oak (Quercus agrifolia) and -smaller, scrub oaks (Quercus dumosa), with an understory of coastal sage annuals, herbs, and grasses. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June e, 1992 II -D-1 Walnut Woodland Interspersed with oak woodlands and chaparral on some slopes, especially in Tonner Canyon, are woodlands with the dominant tree being California Walnut trees puglans californica), sometimes called black walnut trees. Understory plants are grasses and coastal sage herbs, similar to oak woodlands and chaparral. Riparian Woodland In contrast to the oak or walnut woodlands, riparian vegetation typically follows watercourses or annual sources of water. There are few lakes or ponds in the area, most of which are either man-made or within Tonner Canyon. There ore few perennial creeks or channels, although many local channels carry significant amounts of water for short periods of time during rainy periods. The sphere of influence (Tonner Canyon) and a few canyons within the City support a variety of stream -side or hydrophilic (water -loving) vegetation such as willow (Salix spp.), cottonwood (Populus spp.), white alder (Alnus rhombifolia), Western Sycamore (Platanus racemosa), and cat -tail (Typha spp.), among others. Disturbed Areas Many areas of the City have been disturbed by human activity such as grading, landscaping, weed abatement, etc. to the point that they only support mainly weedy or invasive plants, such as Russian Thistle (Salsola australis), cactus (Opuntia spp.), Curly dock (Rumex crispus), Filaree (Erodium cicutarium), Dove Weed (Eremocarpus setigerus), sunflowers (Helianthus spp.), tree tobacco (Nicotiana glauca), and wild mustard (Brassica spp.). In may areas, non-native grasses and weeds have largely supplanted native grasses and plants, so that only introduced grasses such as Brome or Cheat (Bromus spp.), Barley (Hordeum spp.), and Fescue (Vulpia spp.) remain today. b. Locol Plant Communities The lands within the City are largely developed, and contain human structures and landscaped materials. Scattered throughout the City are isolated pockets of native vegetation (eg. hillsides with coastal sage or oak grasslands). Figure II -D-1 shows areas that still contain native plant communities remaining within Diamond Bar. There are few remaining natural areas with substantial native plant communities, with the exception of the sphere of influence (Tonner Canyon). Hillsides range from mainly landscaped on manufactured slopes to more native plants on natural slopes. Plants on undisturbed hillsides change depending on moisture, orientation to the sun, and elevation. Sage scrub, chaparral, and disturbed plants mix with each other on many slopes throughout the City. Generally, sage scrub plants are most often found on the lower slopes, changing slowly to "soft" (chomise) chaparral, then finally reaching "hard" (woody) chaparral if conditions are right. Within the City, the only slopes with chaparral vegetation are in the undeveloped, southern portion of "The Country' development. These ridges and canyons also support extensive oak and walnut forests, which blend into the undisturbed Tonner Canyon area further south (see Natural Diversity Data Base later in this section). An examination of woody materials on these hillsides indicates there has not been a major brushfire through the chaparral for at least a decade. These rugged, southeast -facing hillsides also contain numerous firebreaks and access roads which are no doubt used by many "Country" residents as equestrian and hiking trails. Hillsides with oak and walnut woodlands still exist in the City in three locations; between Brea Cutoff and Pathfinder Roads west of the 57 Freeway, between Pathfinder and the corporate office park on both sides of the freeway (including east of Sandstone Canyon), and in the central and southern portions of "The Country" development. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June S. 1992 II -D-2 Several slopes In the City containing remnant sage scrub and chaparral plants exist, such as behind (east oo the corporate office park east of Golden Springs Drive, from Grand Avenue south to the 57 Freeway, and In the Upper Sycamore Canyon area. Two canyons in the City support extensive riparian and oak woodland communities. 'Sandstone Canyon', as It Is commonly called, is located north of Pathfinder Road, west of the 57 Freeway and Steep Canyon. It contains a meandering stream which was previously fed from a perennial spring south of Pathfinder which has since been covered over by two large reservoir tanks. It now appears to be fed by regular landscape irrigation runoff from the houses and offices built west and south of the canyon, respectively. This lush canyon contains arguably the oldest oak and walnut trees in the City. It has an oak -canopied path along next to the stream, as well as a path along the steep ridgetine to the east. The eastern slope of this ridge also contains a remnant oak and walnut woodland (refer to previous discussion and to the section on the Natural Diversity Data Base later In this section). The 'Upper Sycamore Canyon' is a large area (+300 acres) containing several inter -connected canyons north of Grand Avenue between Diamond Bar Boulevard and Leyland Drive. Two of the main canyons, adjacent to two of the main roads in the area, contain ephemeral streams. "Steep Creek' travels along the north side of steep canyon road, while "Clear Creek" Is located just west of Clear Canyon Road (see Figure II -13-1). These drainages (Clear Creek in particular) contain some of the largest oak and sycamore trees in the City, and a number of walnut trees as well. Much of the drainage from this area eventually flows into lower Sycamore Canyon, which is a designated park. For additional information on drainage and sedimentation problems, see Section II -C, Drainage and Flood Control. The Tres Hermanos area, the largest undeveloped portion of the City of Diamond Bar, has been grazed extensively by cattle, and is essentially barren with a few scattered stands of oak trees within the Tonner Canyon drainage. Within the City, there are few unplanted slopes that contain only one particular plant association, since most slopes have had some type of previous disturbance such as grading, clearing for fire protection, or human traffic. Most slopes within the City contain a mixture of species. For example, there are hillsides in the "Steep Creek" area with a riparian stream bottom, oak and a few walnut trees on the lower slopes, then only red mustard, some weeds, and isolated cactus on the upper slopes. Most vacant or previously graded lots within the City support disturbed species, or remnant coastal sage plants. Occasionally, some heartier shrubs such as toyon or Lemonadeberry survive from previous chaparral growth. The type of plants associated with disturbed areas depends on the extent and frequency of disturbance, as well as its proximity to undisturbed native areas. For example, a hillside once cleared for fire protection that is not regularly cleared, but is adjacent to hillsides with native scrub plants, is for more likely to support native species compared to small vacant lots that are surrounded by urban development. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1 W2 II -D-3 ) H22 2 &§ $!�■« ® §■�` R ` ! f f uj LLJu z ƒ z §aƒ ! LLJ q » \ u � e a K Table ll- -1 Local plants Scientific Name Common Name Adenostoma fasciculaium Chomise Amarontus albus Pigweed Ambrosia psilostachya Western Ragweed Artemisia californica California Sagebrush Asclepias californica California milkweed Asclepias erioscarpa Woolypod Milkweed Astragalus trichopodus locoweed Avena barbata Slender Wild Oct Avena fatuo Common Wild Oat Bocchoris glutinosa Mulefat Baccharis pilularis Coyote Bush Brassica kaber Charlock Brassica nigra Black Mustard Brassica raps Field Mustard Bromus diandrus Ripgut grass Bromus mollis Soft Chess Bromus rubens Red Brame Carduus pycnocephalus Italian Thistle Centaurea rnilitensis Tacalote Chenopodium album Lamb's Quarters Cirsium californicum California Thistle Claytonia perfoliata Miner's Lettuce Convovulvus arvensis Field Bindweed Conyze canadensis Horseweed Cuscuta spp. Dodder Cynodon dactylon Crabgrass Datura meteloides Jimsonweed Daucus pusilus Rattlesnake Weed Dryopteris arguta Wood Fern CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -D-5 Table q -D-1 Local Plants Scientific Name Common Name Dudleya lanceolota Live Forever Elymus condensatus Giant Wild Rye Encello calfornica California Encelio Eremocarpus setigerus Dove Weed Eriogonum fasciculotum California Buckwheat Erlophyllum confertiflorum Golden Yarrow Erodlum cicutarium Red -stemmed Filaree Euphorbia albomarginaia Rattesnoke Weed Festuca megalura Foxtail Fescue Gallium nuftallil Bedstraw Gnaphollium californiocum California Everlasting Grindelia robusta Gum Plant Haplopoppus venetus Goldenbush Helionthus annus Sunflower Hemizonia faciculota Torweed Heteromeles arbutifolia Toyon Heierotheca gradifloro Telegraph Weed Hordeum leporinum Foxtail Barley Juglons colifornia California Black Walnut Kechiello cordifolio Penstemon lactuca serriola Prickly Lettuce Lonicera subspicato Chaparral Honeysuckle Lotus scoparius Deerweed Lupinus succulentus Lupine Molocothamus fasciculatus Chaparral Mallow Marsh macrocarpus Wild Cucumber Morrubium vuigore Horehound Medicago polymorpha Burrclover Melilotus indicus Yellow Sweet Clover CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -D-6 Table II -D-1 Local Plants Sclenttfic Name Common Name Mimulus longiflorus Sticky monkeyflower Nasturtium officinole Watercress Nicotiano glauca Tree Tobacco Opuntia littorolis Prickly Pear (Beavertail) Cactus Picris echioides Ox Tongue Plotanus racemoso Western Sycamore Prunus Ilicifolia Hooly-leaved Cherry Rincinus communis Costorbeon Quercus ogrifolia Coast Live Oak Quercus dumoso Scrub Oak Raphanus sotivus Wild Radish Rhamnus colifornica Coffeberry Rhamnus ilicifolia Holly -leaved Redberry Rhus Integrifolia Lemonadeberry Rhus lourina Laurel Sumac Rhus ovato Sugarbush Rhus trilobata Squawbush Rhus ursinus California Blackberry Ribes speciosum Fushia-flowered Gooseberry Rumex crispus Curley Dock Sabucus mexicana Blue Elderberry Salix gooddingii Black Willow Salsola iberico Russian Thistle (Tumbleweed) Solvio apiono White Sage Salvia leucophylla Purple Sage Salvia mellifera Black Sage Schinus molle California Pepper Silybum marianum Milk Thistle Solanum xanti Nightshade CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .June 8, 1992 II -D-7 Table 11-13-1 Local Plants Scientific Name Common Name Stelloria media Chickweed - Stephonomieria exigua Stephanomieria Stipa lepida Small -flowered Needlegrass Toxicodendron diversilobum Poison Oak Trichostema lanceolatum Vinegarweed Typha latifolia Broad-leaved Cattail Source: Compilation of species lists from local environmental documents and field surveys (Plor"ng Network 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -D-8 C. Wildlife The sum of all physical and biological conditions necessary for a particular species to function (e.g. live, eat, reproduce) is called its habitat. The combination of coastal and mountain conditions in the area create a wide range of habitats for local wildlife. To a large degree, the types and location of plant communities determines the diversity of habitats available for local wildlife. Many animals, especially birds, small mammals, and rodents, can utilize both the valley floors and surrounding uplands for food and shelter. Ground squirrels, mice, rats, songbirds, and other opportunistic creatures can find food almost anywhere, including the more urbanized areas within the City. Table_ II -D-2 provides a list of the wildlife species generally expected in the City and sphere of influence, and was compiled using the most recent local environmental documents. At present, much of the City is developed, with only isolated canyons and hillsides remaining undeveloped. The major exception Is Tonner Canyon, which supports sizeable areas of riparian woodland. Typical mammals found within the City are those that ore tolerant of human contact, including ground squirrel (Spermophilus beecheyi), cottontail rabbit (Sylvilagus audubonii), California pocket mouse (Perognathus californicus), mole (Scapanus latimanus), and gopher (Thomomys bottae). Less frequent, but often found in the natural canyons or outlying areas are the opposum (Didelphis marsupialis), racoon (Procyon lotor), coyote (Canis latrans), mule deer (Odocoileus hemionus), and striped skunk (Mephitus mephitus). Tonner Canyon contains a significant amount of local native animals, including deer, grey fox (Urocyon cinereoargenteus), bobcat (Lynx rufus), weasel (Mustela frenata), racoon, etc. Birds that frequent the City include songbirds such as the Western Meadowlark (Sturnella neglecta), common raven (Corvus corax), mourning dove (Zeinaida macroura), seagulls (Larus spp.), and mockingbirds (Mimus polyglottus). Birds that can be found in outlying areas or natural canyons include the California Quail (Lophor4w californicus), turkey vulture (Cathartes aura), red-tailed hawk (Buteo jamaicensis), white-tailed kite (Elanus leucurus), Phoinopepola (Phaenopepola nitens), wrentit (Chamaea fasciata), Acorn woodpecker (Melanerptes formicivorus), goldfinch (Carduelis psaltria), waxwing (Bombycilla cedrorum), scrub jay (Aphelocoma coerulescens), and flycatcher (Mylarchus cinerascens). Tonner Canyon supports all or most of these birds on a year-round basis, as well as providing habitat for the Red -Shouldered Hawk (Buteo lineatus), Cooper's Hawk (Accipiter cooperir), great horned owl (Bubo virginianus), and screech owl (Otus asio). Few reptiles, other than the Western fence lizard (Scaloperous occidentalis) and side-blothed lizard (Uta stansburiana), are found within the City. Occasionally, the common king snake (Lampropetlis getulus), or striped racer (Coluber lateralis) are found in City canyons. During certain times of the year, the Western Diamondback Rattlesnake (Crotalus atrox) or Red-Daimond Rattlesnake (Crotalus rubers), can pose a threat on native or weedy hillsides, but are becoming less common as development encircles the City. The Southwestern Pond Turtle (Clemmys marmorata pallida) may also be found in Tonner Canyon, although it has not specifically found in the portion of the canyon within the City's sphere of influence. The Pacific tree frog (Hyla regilla) and western load (Bufo boreas) are the only amphibians found regularly in the City, although the arboreal salamander (Aneides ligubris) and slender salamander (Batrachoseps attenuatus) can be found along stream bottoms or in wetter canyons. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8,1992 II -D-9 Table II -13-2 Local Wildlife SCIENTIFIC NAME COMMON NAME AMPHIBIANS Aneides lubugrisl Arboreal Salamander Bottrachoseps attenuatus California Slender Salamander Bufo boreas Western Toad Hyla regillo Pacific Tree Frog REPTILES Clemmys marmorata pallidal Southwestern Pond Turtle Cnemidophorus tigris Western Whiptail Coluber lateralis Striped Racer Crotalus atrox Western Rattlesnake Crotalus rubers Red -Diamond Rattlesnake Diodophis amobilis Western Ring -Neck Snake Gerrhonotus multicarinatus Southern Alligator Lizard Lampropeltis getulus Common Kinagsnake Lampropeltis pyromelona Banded Kingsnake Lichanura roseofusca Rosy Boa Masticophus lateralis Red Racer Phrynosoma corrannatum Horned Lizard Pituophis canfenofer Gopher Snake Pituophis melanoleucus California King Snake Sceloporus occidentialis Western Fence Lizard Uta stonsburiono Side -Blotched Lizard MAMMALS Ammospermophilus leucurus Antelope Ground Squirrel Bos Bovis Domestic Cow Canis domesticus Feral Dog Canis latrans Coyote Didelphis morsupiolis Opossum Dipodomys sp. Kangaroo Rat Fells domesticus Feral Cat lepus colifornicus Block -tailed Hare Lynx rufus Bobcat Mephitus mephitus California Striped Skunk Most Ikety supported in Tonner Canyon. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -D-10 Table U -D-2 Local Wildlife SCIENTIFIC NAME COMMON NAME MAMMALS Microtus californicus (Conrd]l Mustela frenotal Neotoma fuscipes Odocoileus hemionus Otospermophilus beecheyl Perognathus californicus Perognothus longimembris Peromyscus spp. Procyon lotor Ratus norvegicus Reithrdontys megalotis Scapanus latimanus Sciurus griseus Spermophilus beecheyi Spilogole putorius Sylvilagus audubonii Sytvilagus bachmani Taxidea taxusl Thomonys bottae Urocyon cinereoargenteusl Accipiter cooped Acciptier striatus Aeronautes saxatalis Aphelocoma coerulescens Archilochus alexandri Bombycilla cedrorum Buten jamaicensis Buteo lineatus Bubo virginionus Calypte anna Calypte costae Most likely supported in Tonner Canyon California Vole (Meadow Mouse) Long-tailed Weasel Dusky -footed Woodrat Mule Deer California Ground Squirrel California Pocket Mouse Little Pocket Mouse Deer Mouse Racoon Norway Rat Western Harvest Mouse Broad -handed Mole Western Grey Squirrel California Ground Squirrel Spotted Skunk Audubon's Cottontail Brush Rabbit Badger Botta Pocket Gopher California Grey Fox Cooper's Hawk Sharp -shinned Hawk White -throated Swift Scrub Jay Black -chinned Hummingbird Cedar Waxwing Red-tailed Hawk Red -shouldered Hawk Great Horned Owl Anna's Hummingbird Costa's Hummingbird CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -13-1 1 Table ll D-2 Local Wildlife SCIENTIFIC NAME COMMON NAME BIRDS Comphylorhynchus brunnei Cactus Wren (Cd) Carduelis psoltria Lesser Goldfinch Corpodocus mexicanus House Finch Cathartes aura Turkey Vulture Chamaea fasciata Wrentit Charadrius vociferus Killdeer Colaptes ouratus Common Flicker Columba fasciata Band -tailed Pigeon Columba Uvia Rock Dove Corvus branchyrhynchos Common Crow Corvus corax Common Raven Elanus leucurus White -toiled Kite Eremophila alpestris Horned Lark Euphagus cyanocepholus Brewer's Blackbird Falco sparvorius American Kestrel Falco mexicanus Prairie Falcon Geococcyx califorianus Roadrunner Hirundo rustica Barn Swallow Icterus parisorum Scott's Oriole Lanius ludovicianus Loggerhead Shrike Larus spp. Seagulls Lophortyx colifornicus California Quail Melanerptes formicivorus Acorn Woodpecker Mimus polyglottus Mockingbird Myadestes townsendi Townsend Solitaire Myiarchus cineroscens Flycatcher Otus asio Screech Owl Porus inornatus Plain Titmouse Passer domesticus House Sparrow Phainopepola nitens Phainopepola Pholoenoptilus nuttallii Dusty Poorwill Phasianus colchicus Pheasant Picoides albolarvatus White -headed Woodpecker Pipilo erythrophthalmus Rufous -sided Towhee Pipilo fuscus Brown Towhee CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-D-12 Table 1�a2 Local Wildlife SCIENTIFIC NAME COMMON NAME BIRDS Psaltriparus minimus Common Bushtit (Cont'd) Sayornis soya Say's Phoebe Spinus psoltria Lesser Goldfinch Spinus tristis American Goldfinch Spizella atrogularis Black -chinned Sparrow Spinus tristis American Goldfinch Spizella brewers Brewer's Sparrow Sturnelia neglecta Western Meadowlark Sturnus vulgaris Starling Thryomones bewickii Bewick's Wren Toxostoma redivivum California Thrasher Turdus migratorus American Robin Tyto alba Barn Owl Zenaida mocroura Mourning Dove Source: Compilation of species lists from local environmental reports (Planning Network 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June b. 1992 II -D-13 d. Sensitive Species While development of the City may not be totally compatible with preservation of native plants and wildlife, it Is possible to strike a balance between these conflicting goals. The major focus on native plant and animal protection is: Identifying those species considered sensitive to human activity or that need protection from decline, and; Identifying those areas near or adjacent to natural areas that are undisturbed and/or can be maintained or expanded to support or preserve native wildlife. . tt is the responsibility of various agencies to prevent the loss of or damage to biological species. The U.S. Fish and Wildlife Service Is responsible for designating species of nation-wide concern, while the California Department of Fish and Game Is responsible for designating species of State-wide concern. These agencies exercise their powers under the federal and State Endangered Species Acts, respectively. These agencies coordinate their efforts by classifying the sensitivity of vegetation and wildlife (such as rare or endangered) (CDFG 1990). Federal Regulations Under the Endangered Species Act (1973), species that are officially listed as endangered or threatened are afforded full legal protection from harm. Species that have been proposed for listing as either endangered or threatened are afforded limited protection under the - Act. The term 'endangered" refers to "any species, including subspecies (and varieties), that are in danger of extinction throughout all or a significant portion of its range". The term "threatened' refers to 'any species, including subspecies (and varieties), likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range'. Finally, the term 'proposed endangered or threatened" refers to "species for which a proposed regulation has been published in the Federal Register, but no final rule has been issued yet" (CDFG 1990). SWa Regulations Under the California Endangered Species Act (1984), species can be classified as rare, threatened, or endangered. The term mrarea means that "although not presently threatened with extinction, it Is in such small numbers throughout its range that it may become endangered If Us present environment worsens". The term "threatened" means that "although not presently threatened with extinction, it is likely to become an endangered species in the foreseeable future in the absence of special protection and management efforts". Finally, the term "endangered' means 'the prospects of survival and reproduction of the species are in immediate jeopardy from -one or more causes'. Species included in any of these three categories are afforded protection under the Act, as are Candidate species which are being considered for one of the three major classifications. Species that are considered candidates (of various types) for possible listing as endangered or threatened are afforded no federal legal protection under the Endangered Species Act at present. However, the California Department of Fish and Game has begun looking more closely at Candidate species and attempts to provide some level of protection, where appropriate, through its consultation authority under the California Environmental Quality Act (CEQA). For example, the U.S. Fish and Wildlife Service may classify a bird as a Category 1 species, which means it is officially endangered. This classification carries legal protection such as levying fines for damaging or killing individual animals under the U.S. Endangered Species Act of 1973. They might classify another species as Category 2, which means it will be studied to determine if it is actually endangered. Category 2 species may eventually become Category 1 species (actually listed as endangered), or it may be determined that the species is not endangered; it would then be taken off of the list of sensitive species. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -13-14 Federal and State lists on sensitive species are continually updated to reflect the most current information on species habitat and sensitivity. The following information is from the California Deportment of Fish and Game through its computerized Natural Diversity Data Base maps. Natural Diversity Data Base (NDDB) Diamond Bar is located within for the San Dimas and Yorba Linda quadrangles of Los Angeles and Orange counties, respectively. The NDDB identified fourteen (14) significant resource areas or sites that affect the planning of Diamond Bar, although only three are within the City limits, and six are within the sphere of influence. The locations of all these sites are shown in Figure II -D-2. City of Diamond Bar The NDDB printout and species mapping for Diamond Bar indicates there are three (3) sites within the City limits that can be considered important biological resources: DF&G Site 2600 This is a group of three canyons and hillsides in the Puente Hills on the west side of the 57 Freeway south of Pathfinder Road. This area contains "California Walnut Woodlands", which are similar to oak grasslands but support California Walnut trees (Juglans califomica) as well as coast live oak trees (Quercus agrifolia). The two northern canyons are isolated from nearby undeveloped lands to the west by development and Brea Cutoff Road. The southernmost canyon occupies both sides of Brea Cutoff Road, just north of the 57 Freeway. The vegetation in all three canyons is in fairly healthy condition. This plant association has no official State or federal status and was last surveyed in 1988. DF&G Site 2633 This site contains remnants of "California Walnut Woodland", but is split into two parts by the 57 Freeway. It is generally located between Pathfinder Road and the 60 Freeway interchange. Some of the larger eastern portion of this site was removed during grading for the corporate office center south of Golden Springs Drive. The western portion consists of a small canyon and hills along Brea Canyon Road, and is still in fair condition. The site was last assessed in 1984. DF&G Site 2677 This is another "California Walnut Woodland" which also contains coast live oak trees. Since its survey in 1985, this area has become the private open space/recreation park for "The Country" development. Much of the natural slopes and vegetation have been maintained. This area drains southeast into Tanner Canyon. Sphere of Influence The NDDB survey and species mapping for Diamond Bar identified six (6) sites within the City's sphere of influence that can be considered important biological resources: DF&G Sites 2578 and 2610 These two canyons drain south into Tanner Canyon, and contain mature "California Walnut Woodlands". In addition, these sites contain coast live oak trees and riparian vegetation. DF&G Sites 2643 and 2657 These two small canyons contain "Southern Coast Live Oak Riparian Forests and drain northwest into Tanner Canyon. They were last surveyed in 1988 but only with the use of aerial photos. • DF&G Site 2716 This area consists of two sizeable canyons, Lions Canyon and an unnamed canyon, both located southeast of Tanner Canyon. The upper "headwaters' of these canyons are within the City's sphere of influence, although the majority (the middle and lower portions) of the canyons are south of the sphere, and drain into Carbon Canyon Creek in Orange County. These canyons contain "California Walnut Woodlands" along with chaparral and scrub plants. They were last surveyed in 1985 with aerial photos. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -D-15 DF&G Site 2681 This area contains an extensive 'California Walnut Woodland' on a large cayon and stream bench of Tanner Canyon. The canyon drains northwest off of the north -facing ridgeline, and supports a variety of riparian species. Directly through the ridge is the headwater canyon of the Sonome Canyon, which drains away from Tonner Canyon toward Carbon Canyon in Orange County. Adjacent to the City There are also five (5) sites that are just outside of the City limits or sphere of Influence, but are an integral part of the locally important plant communities or notable biological resources: • DF&G Site 2591 This canyon contains a "Southern Coast Live Oak Riparian Forest". It Is fairly shallow .and is the first canyon south of Brea Cutoff, north of the 57 Freeway. It forms a common drainage into Brea Canyon Creek with the southern canyon of DF&G Site 2600. This and the other oak forest sites along the Brea Canyon (DF&G Sites 2600, 2633, and 257 1) are all remnants of once extensive oak and walnut forests in the eastern Puente Hills (Weintraub 1990). DF&G Site 2571 These five canyons are just outside of the City limits, southwest of Brea Cutoff, north of the 57 Freeway. They are part of the once continuous oak and walnut forests that covered these hillsides northwest of Brea Canyon Creek. These five canyons contain "Southern Coast Live Oak Riparian Forest," are considered to be a significant group of coast live oak (Quercus agrifolia), and was last surveyed in 1985. As with Site 2600, it has no official federal or State protective status. It should be noted that the portions of this area not included in Site 2571 are included In the Tonner Conyon/Chino Hills SEA 15 (see Significant Ecological Areas later in this section). DF&G Site 2703 (Not shown on Figure II -D-2) Although not located within the sphere of influence, it represents a 1987 sighting of a Southwest Pond Turtle (a Category 2 species) in the lower drainage of Site 2716 (Lions Canyon) where it enters Carbon Canyon Creek. • DF&G Site 2715 This site is the Arnold Reservoir, within the Tonner Canyon drainage basin. Although this site is immediately east and outside of the Diamond Bar City limits, it does represent another sighting of the Southwest Pond Turtle (see Site 2703). It should be noted that this sighting is undated, so there is no way to know how long ago the species was sighted here. However, from these two sightings, the Tonner Canyon drainage should be consideredappropriate habitat for this species, which Is presently in federal Category 2. DF&G Site 2588 This canyon drains south into Tonner Canyon, and contains mature "California Walnut Woodlands". It is closely associated with DF&G Sites 2578 and 2610, which are directly across Tonner Canyon from this canyon. Sites of Local Concern Two additional areas that contain plants similar to these DF&G sites are: Sandstone Canyon just west of DF&G Site 2633, and Upper Sycamore Canyon CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .lune 8, 1992 II -D-16 Sandstone Canyon contains a mature riparian oak woodland with a meandering stream. It supports a large variety of local plants and wildlife, and may still have access to a wildlife movement corridor connecting to the Puente Hills to the west. The Monterey Blue Butterfly, considered endangered by the State, is reported to have been observed by local naturalists in this canyon (Schad 1990). However, the State has no record of sighting for this species. Upper Sycamore Canyon comprises a series of canyons north of Grand Avenue, between Diamond Bar Boulevard and Leyland Drive. This area contains a mixture of riparian, chaparral, and coastal scrub vegetation, and is one of the largest remaining undeveloped areas in the City. It is also immediately visible by travelers on the 57/60 freeways and Diamond Bar Boulevard. "California Native Plant Society In addition to State and federal agencies, the non-profit California Native Plant Society (CNPS) maintains lists of plants that have special local, regional, or State-wide concern (CNPS 1988). Although the CNPS maintains their lists independent of Fish and Wildlife or Fish and Game, these agencies nevertheless coordinate their protective efforts by continually updating and refining their lists as new information on species becomes available. The only plant species in the Diamond Bar area which the CNPS considers sensitive is the many -stemmed dudleya (Dudleya multicauliis). This species is found on stony ground of elevations below 2500 feet, generally in chaparral or coastal sage scrub associations. It is considered to be threatened, mainly because its habitat is being lost through grading for development. Although the Natural Diversity Data Base did not indicate any sightings of this species within the City limits or sphere of influence, it has been repeatedly observed in San Dimas, north of the City, at roughly similar elevations (DF&G Sites 2675 and 2676). This species is on CNPS list 18, meaning that it is "rare, threatened, or endangered in California and elsewhere' (CNPS 1988). This species is categorized by the CNPS as 1-2-3 according to the Rarity -Endangerment -Distribution (R -E -D) index. The #1 means it is "rare, but found in sufficient numbers and distributed widely enough that the potential for extinction or extirpation is low at this time'. The #2 means it is'endongered in a portion of its range", while the #3 means it is 'endemic (native) to California". This species has no official State status, but it is presently classified as a "candidate species" (Category 2) by the U.S. Fish and Wildlife Service. This means "Information now in the possession of the U.S. Fish and Wildlife Service indicates that proposing to list them as endangered or threatened is possibly appropriate, but for which substantial data on biological vulnerability and threat(s) are not currently known or on file to support the immediate preparation of rules' (CNPS 1988, CDFG 1990). In addition, 'candidate species" are those that the U.S. Fish and Wildlife Service is considering for listing as endangered or threatened status, but for which there are no published rules. These species have no formal protection according to the Endangered Species Act. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -D-17 N D LD zz Z W LU co LV L:c? e. Significant Ecological Areas In 1976, the Los Angeles County Regional Planning Office, in conjunction with the County Parks Department, designated over 60 Significant Ecological Areas (SEAS) throughout the County. Development and planning on unincorporated lands within these areas is monitored by the Significant Ecological Area Technical Advisory Committee (SEATAC). The County's SEATAC committee has categorized the SEAS into the following classifications. SFA Class Description (1) Habitat for rare, threatened, or endangered plants or animals (State or federal). (2) Biotic communities, vegetative associations, and habitat of plant and animal species that are either one of a kind, or are restricted in distribution on a regional basis. (3) Biotic communities, vegetative associations, and habitat of plant and animal species that are either one of a kind, or are restricted in distribution in Los Angeles County. (4) Habitat that, at some point in the life cycle of a species or group of species, serves as a concentrated breeding, feeding, resting, or migrating ground, and is limited In availability. (5) Biotic resources that are of scientific interest because they are either an extreme in physical/geographicol limitation, or they represent an unusual variation in a population or community. (6) Areas important as habitat for game species or fisheries. (7) Areas that would provide for the preservation of relatively undisturbed examples of the natural biotic communities in Los Angeles County. (S) Special Areas - Areas that are worthy of inclusion, but that do not fit any of the other criteria. The central and southern portions of Tanner Canyon are classified as a "Significant Ecological Area' by the Los Angeles County Department of Regional Planning. Figure II -D-3 shows the present boundaries of this SEA as approved by the SEATAC Committee. Tanner Canyon The Diamond Bar Sphere of Influence encompasses the central portions of Tanner Canyon, north of the Los Angeles/Orange County line. Tanner Canyon represents the heart of the Tonner CanyorVChino Hills Significant Ecological Area" (SEA 15), because it is a "regional riparian woodland complekm. It meet the Class 7 criteria, meaning it: 1) is completely or nearly undisturbed, 2) has a variety of habitats, 3) is large enough to support representative plant and animal groups, and 4) is more or less isolated from outside impacts by physical boundaries (LACDRP 1976). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -D-19 Toner Canyon contains limited development at present. Current uses include oil production in the lower portion, near the 57 Freeway, by Unocal and several other oil companies. Some of the lower canyon and all of the middle canyon are used by the Boy Scouts of America, who own 50 percent of the canyon, for their Firestone Boy Scout Ranch. The watershed of this canyon covers 9 square miles (+5700 acres). It is approximately 9 miles long and varies in width from half a mile to over a mile in some places. It contains a perennial stream that supports extensive riparian, oak woodland, walnut woodland, chaparral, and coastal sage vegetation. This canyon is considered an important biological resource by the County of Los Angeles. Despite intrusive uses (oil production and scout camping), this canyon still represents a unique vegetation and wildlife reserve. Its importance is enhanced by its location at the intersection of three urbanizing counties; Los Angeles, Orange, and San Bernardino. The City's sphere of influence encompasses over 350 acres of SFA 15, as shown in Figure II -D-3. Tonner Canyon contains seven (7) biological resource areas as identified by the California Department of Fish and Game's Natural Diversity Data Base program. These resource areas are a combination of oak and walnut riparian forests in rugged canyons draining into Tonner Canyon. This reinforces the concept that Tonner Canyon acts as a regional plant and wildlife "sanctuary" or reserve in its present state. it should be noted that a significant amount of the Chino Hills portion of the SEA (outside of Tonner Canyon) Is west of the 57 Freeway, and a small portion of this area is just outside of the Diamond Bar City limits, adjacent to DF&G Site 2591 and encompassing DF&G Site 2571 (see Sensitive Species). Figures II -D-2 and II -D-3 show the locations of these biological resource areas. it Tonner Canyon was developed to the point that its biological resources were largely eliminated, there would only be two other representative riparian SEAS in Los Angeles County: Buzzard Peak/San Jose Hills and Powder Canyon/Puente Hills (SEA 17). Buzzard Peak/San Jose Hills (SEA # 16) is located approximately 6 miles north of Diamond Bar, while the Powder Canyon/Puente Hills (SEA 17) is located about 4 miles west of the City. It should be noted that there has been an historical connection between Sandstone Canyon (northwest of 57 Freeway at Pathfinder) and SEA 17 through the Puente Hills. However, the region surrounding and including SEA 17 is being considered for development in the near future. The County of San Bernardino adopted the Chino Hills Specific Plan in 1982. This land planning document identified part of the upper drainage of Tonner Canyon as the Tres Hermanos Ranch. A village -typed planned community was proposed for Tonner Canyon with portions the ridgeline and water courses preserved as open space (CPP 1987)(EDAW 1982). The major purpose of the SEATAC report was to identify areas that should be preserved as regional biological resources. Loss of these three areas through cumulative development would seriously degrade the long-term viability of native plants and animals in this portion of the Los Angeles basin. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .June 8, 1992 II -D-20 2 a\ ƒ CO, ©Q 204 \ z k/} CL z | fit/00 \ 6 \ ` wLLI y / �J■�/} z LD U) LU } / ) 2. ISSUES AND OPPORTUNITIES The major Issues facing the City regarding biological resources deal with possible preservation of natural areas (canyons, hillsides, etc.), within the City versus development potential. While some of these areas may have other physical constraints (such as soil stability) that lend themselves to preservation, the City still needs to address the issue of the need for preserving biological areas on their own merits. There is first a larger question that must be answered regarding biological preservation. A city may decide to preserve a particular piece of land as a biological resource. However, if the parcel is too small, does not contain enough resources to support the plants and animals, or it is Isolated from nearby natural or undeveloped areas, it may not be sufficient on its own to adequately preserve biological resources. This is the most important factor when deciding if a particular area Is appropriate for preservation. a. Preservation of Land within the City The City still has an opportunity to preserve or protect various local natural areas within the City limits. However, the timing of any action by the City is crucial, since other potential areas have already been developed, and more will be lost soon if no action is taken. Even if the City eventually decides to allow development of these areas, it should take the opportunity now to study their potential preservation. Once they are developed, their potential for preservation will be lost forever. Prime areas for possible preservation within the City, as identified by the Natural Diversity Data Base (State Department of Fish and Game), are shown in Figure II -D-2 and include: The hills and canyons containing oak and walnut woodlands, west of the 57 Freeway north of Pathfinder Road (not including Brea Cutoff Road): Remaining walnut groves along both sides of the 57 Freeway, between Pathfinder Road and the 60 Freeway. In addition, there are several locally identified areas that could also be considered for preservation (see Figure II -13-2): • Sandstone Canyon, located west of Brea Canyon Road and north of Pathfinder Road, • The Upper Sycamore Canyon area, north of Grand Avenue between Diamond Bar Boulevard and Leyland Drive, • The remaining natural slopes with native vegetation behind (east of) the corporate offices off of Golden Springs Drive (includes east side of walnut groves mentioned previously), • Any wooded slopes or streambeds in the Tres Hermanos area, especially if they are part of the Tanner Canyon drainage. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1 M II -D-22 b. Environmental Planning The City may wish to place the following areas, which ore outside of the City limits and sphere of Influence, within an "Environmental Constraints Line": West side of Brea Cutoff Road to include the drainage along the west side of the road plus the first canyon to the south, All of Tanner Canyon drainage not already within the City or its sphere of influence. City staff could then use this designation to justify working more closely with the responsible jurisdictions to best coordinate land planning for these areas. C. Wildlife Corridors/Troils As previously stated, setting aside open or natural areas will not guarantee their value for preserving biological resources unless they fullfill the habitat requirements of the resources. Preserving some or even all of the isolated canyons and hillsides suggested previously may help protect the valuable vegetation present (oak and walnut trees), but would probably not provide sufficient habitat for diverse animal populations. Large mammals will be forced out of these areas as development surrounds them, even if they are utilizing them now to a significant degree. Birds and small mammals (squirrels, rabbits, etc.) will probably continue being able to utilize these areas, although the types and numbers of animals using these areas will change. Potential areas for trails to link resource areas could be in the following locations: • The northern slopes of Tonner Canyon that form the southern and southwestern boundaries of 'The Country" development; • Sandstone Canyon, both along the streambed and the eastern ridge; • Along the oak woodland slopes, northwest of the 57 Freeway at Pathfinder Road; • Along the south side of Brea Cutoff (if the oak woodland areas south of the road can be brought into the City's sphere of influence); and • Upper Sycamore Canyon, connecting Sycamore Park to both the Tres Hermanos area and/or the Summit Ridge Park area. As development begins to surround natural areas, native species face increased competition from weedy, invasive, or pest species. For example, landscaping installed next to a natural canyon would probably support a number of song birds, which could outcompete more reclusive native riparian bird species for food and nesting sites in the natural areas. The only way for some of these areas to remain viable as complete ecosystems, instead of isolated islands of native vegetation, is to provide connections to nearby undeveloped land or natural areas. For example, the southern end of Sandtone Canyon has already been cut off from its historical water source (a spring), and has been further blocked off at its northern end by urban development and the junior high school. The last remaining link with larger resource areas is a small canyon to the west that leads into the Puente (La Habra) Hills. If this area is developed, Sandstone Canyon will be completely isolated, even though there is a potential for preserving a significant amount of land in this canyon. On the other hand, if a wildlife corridor were somehow maintained to the west, animals might be able to travel between here and the undeveloped Puente Hills and canyons west of the City. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -D-23 Another example is the Upper Sycamore Canyon area, north of Grand between Diamond Bar Boulevard and Leyland Drive. Although this is a fairly large, natural area, it has no connection to larger wild areas such as Tonner Canyon. It will eventually become an island of native vegetation which cannot be fully utilized by local wildlife. However, if a way were found to connect these canyons with Lower Sycamore Canyon to the west, and the undeveloped land in Tres Hermanos, or (even better) with Tonner Canyon, a much greater variety of native wildlife would be able to utilize this area over the long term. It may be possible to combine wildlife corridors with trails linking open space areas, although larger wildlife would be less apt to use paths frequented by humans. Suggestions for possible trail locations are shown in Section II -N, Recreation and Open Space. Without connections to larger wild areas, it can be argued that no natural areas should be preserved within the City. However, natural areas provide benefits other than just for biological resources. For discussions on additional benefits, see sections II -A. Landforms and Topography; II -B, Earth Resources and Seismicity; and II -N, Recreation and Open Space. A myriad of factors must be weighed to decide if or what areas should be preserved. d. Environmental Tradeoffs Another factor to consider in determining the most appropriate areas to preserve is the tradeoff between development and biological resource potential. For example, the floors of the canyons west of the 57 Freeway and south of Pathfinder are flat and lend themselves to building. However, they also contain the most walnut and oak trees. The hillsides could be graded for homes, but could also be a good location for community trails. Transferring the density of development to a portion of a site is a common way of allowing for the preservation of another part of the site. However, concentrated development can impact adjacent natural areas to such a degree that they become useless for local plants and wildlife. The issue to density and locational tradeoffs is an important one in determining the overall effectiveness land use policies for natural as well as developed areas. e. Tonner Canyon Tonner Canyon represents a unique biological resource for the entire region. This resource needs to be carefully planned and managed if it is to remain a valuable asset. The City may wish to enter into a joint study of this entire watershed area with the affected agencies and land owners, including the Community of Chino Hills, State Department of Fish and Game, Union Oil, Boy Scouts, Southern California Golf Association, etc. Issues such as flood control, circulation, and future boundaries of the Significant Ecological Area could also be addressed. Other Considerations The City may wish to encourage landscaping with native plants and trees, not only for the biological value, but also for water conservation as well (LACDFFW 1979). The City may wish to disseminate information about oak tree preservation and maintenance (LACDFFW 1988). Residents may also want information on control of tree pests (LACDFFW 1989b) or landscaping for fire prevention (LACDFFW 1989a and 1989c). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, t 992 II -D-24 Residents should be aware that domestic pets that are allowed to roam free in natural areas can significantly reduce local wildlife. Pet owners should keep their animals on leashes at all times when traveling through natural areas, especially near dawn and dusk. in addition, residents should be warned of the potential harm in harassing or killing local wildlife, especially raptors and large mammals. If the State-wide drought continues, the City may wish to investigate irrigating certain coastal sage or chaparral hillsides to protect them from disease and dehydration (CSUF 1990). Since these plants do not require substantial moisture, the water requirements of such a preservation program would be fairly low, and It would yield significant benefits to local plants as well as for fire protection. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8,1 M II -D-25 E. LAND USE 1. E)=NG SETTING a. Historical Land Use Diamond Bar Is located in the southeastern corner of Los Angeles, with two rapidly urbanizing freeway corridors (57 and 60) to the west and north, and the undisturbed Tonner Canyon to the east and south. The City has grown from rolling hillsides once dotted with cattle a hundred years ago into a thriving rural residential community during just the last 30 years. The City Incorporated in 1989, after developing under the jurisdiction of Los Angeles County for almost 30 years. Although touted as one of the first planned communities in the west, Diamond Bar developed mainly as individual detached single family residential tracts, with a minimal amount of commercial and other non-residential uses. Historical patterns of development under the County have created isolated multi -family areas, small commercial centers with limited access, and a general fragmentation of uses in the City. Current land uses within the City of Diamond Bar are primarily residential, with supporting neighborhood commercial centers, freeway frontage retail/commercial, and newly expanding office and professional uses. Theses uses are supported by various roadways and public utility structures. Table II -E-1 provides a summary of all existing land uses in the City, while Figure II -E-1 shows their locations. A detailed breakdown of land uses by traffic zone is also provided in the Land Use Appendix. b. Residential Uses Residential uses are all dwelling units including single-family homes, joint ownership developments such as condominiums or townhomes, apartments, and mobile homes. The City is primarily residential, with 4,952 acres (52%) of the land developed for housing. The City's housing stock comprises 12,589 single family detached units (71.3%). 4,132 condominiums (23.3%), 649 apartments (3.7%), and 294 mobile homes (1.7%). Approximately 616 of the single family units (5%) are on large, "rural' residential lots (one acre or more). In general, development densities are greater in the flatter portions of the City (west), while larger lots predominate in the upland areas (east). Table II -E-1 provides a summary of residential acres and numbers of units by housing type for 1990. Figure II -E-1 shows the location of existing residential uses within Diamond Bar. C. Single Family Development Single-family residential neighborhoods are distributed evenly over the southeast, east, and northeast portions of the City, with some development scattered in the southwest and west portions. Typically, older residential neighborhoods are located in the flatter portions of the City, generally along the east side of the 57 Freeway and north of the 60 Freeway. The majority of new housing stock is located within the hillside areas in the southwest, southeast, east, and northeast. Single-family residential estates are located on large lots in the south and southeast portions of the City. Along the 57 and 60 freeway corridors, single family lots are generally under 10,000 square feet. Detached single family development in these areas have been built at 5-8 dwelling units per acre, which represents over half of the City's entire housing stock. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .lune 8, 1M II -E-1 Typical of most affluent suburban communities In hillside areas, lot size, unit size, and unit price in Diamond Bar generally increase with the degree of slope. East of Diamond Bar Boulevard, development densities decrease to 0-4 units per acre, as lot sizes increase. "The County", a private gate -guarded community, contains 616 homes and occupies 855,5 acres along and just west of the ridge separating the City from Tonner Canyon. Here, lots may be several acres or more, depending on the degree of slope. d. Multi -Family Development While single family development predominates in Diamond Bar, multi -family projects can be found along Diamond Bar Boulevard south of Grand, and on Golden Spring Drive north of Diamond Bar Boulevard. These developments usually occupy small sites along major roadways, and are built at 10-20 units per acres. The more dense multi -family projects (+ 18 units per acre) are usually older condominiums approved by Los Angeles County prior to incorporation. This western half of the City generally contains the older housing, built in the 1960's and early 70's. The City also contains four apartment complexes of moderate size and density (10.9-16.7 units per acre), with most located on major arterials (Diamond Bar Boulevard, Grand Avenue, etc.). A summary of multi -family housing projects within Diamond Bar is provided in the Land Use Appendix. e. Non -Residential Development Non-residential uses comprise 1,867 acres or 19.5 percent of the City's land area. Commercial uses occupy 182 acres (1.9 percent of total), mainly located along Diamond Bar Boulevard and portions of Golden Springs Drive/Colima Road. Office uses occupy approximately 140 acres, with a major 110 -acre corporate office complex located just east of the southern intersection of the 57 and 60 freeways; this Gateway Corporate Center is presently less than half completed. Approximately 85 acres of industriol/business park uses are located along Brea Canyon Road, north of Lycoming Avenue. Parks, public facilities, open space, and roads occupy the remaining 1,463 acres (78.4 percent). Table II -E-1 summarizes the acreages and approximate building areas for existing non-residential land uses in Diamond Bar,while Figure II -E-1 shows the general location of these uses. The building areas given in Table II -E-1 are for existing commercial, office, and business park uses and were calculated based on representative samples of shopping centers, office parks, and industrial parks within Diamond Bar. Building area can be estimated based on Floor Area Ratio (FAR), or the ratio of building area in square feet divided by the total area of the site (in square feet). For example, a building with 17,500 square feet on a 1 acre site (43,560 square feet) has an FAR of 0.40 (17,500 divided by 43,560). Local leasing companies were contacted to obtain total site and building square footages. Detailed data on local FARs was not available, because most shopping centers, supporta variety of commercial, office, and/or business park uses. However, a selective but representative survey of local centers indicates the following FARs are most applicable to Diamond Bar uses, and can be considered representative for planning purposes: Commercial = 0.24, Office = 0.38, and Business Park = 0.32. Commercial There are approximately 125 acres of commercial uses in the City, with only about 12 vacant acres of land zoned for commercial uses at present. These uses are mainly comprised of neighborhood commercial services, located along the Diamond Bar Boulevard corridor. Additional, less significant commercial areas are located adjacent to main commercial centers. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 9,1 vss II -E-2 The main commercial nodes are at the following locations: Country Hills Town Center A neighborhood shopping/theater center with an Alpha Beta supermarket, drugstore, movie theater, various retail stores, service-oriented businesses, and restaurants. • Intersection of Diamond Bar Boulevard/Grand Avenue Commercial land uses are located on oil four corners of the intersection. Developed in a "strip" fashion, typical uses are supermarkets, banks, hardware stores, fast-food stores, restaurants, retail, and service-oriented businesses. The retail centers are known as Standard Brands/1 st Interstate Plaza, Lucky's Plaza, Ralph's/Boston Store Plaza, and Vineyard Bank Plaza. This intersection is considered the actual town center. Intersection of Diamond Bar Boulevard/Golden Springs Commercial land uses are located on the southwestern and northwestern corner of intersection and continue down to the freeway. Commercial uses include retail stores. Vons supermarkets, K -Mart discount variety store. Sav-on drugstore, service oriented businesses, banks, gas station, auto service center, and restaurants. Diamond Bar Boulevard between Sunset Crossing and Highland Valley located along freeway frontage, users such as fast-food restaurants, gas stations and auto services are primary land uses. The Windmill/Ranch Center, and Oak Tree Plaza are among the commercial retail centers. Several office buildings are also located in this area. Colima Road/Brea Canyon Road Commercial uses include neighborhood commercial such as a supermarket and hardware store servicing the residential needs of Diamond Bar and Walnut, freeway frontage commercial uses including gas stations and fast-food restaurants. g. Office/Professional Office uses are generally located along the 57 Freeway at Diamond Bar Boulevard, Pathfinder Road, the intersection of the 57 Freeway and 60 Freeway, and at Sunset Crossing. The new Gateway Center is the most prominent office/professional development in the City, it is visible from both freeways, and is serving the regional/corporate office market. There are approiamately 200 acres of office uses presently within the City, although this figure includes some vacant land already planned for development in the Gateway Center. h. Industrial Industrial land uses represent a total of about 112 acres in the City, and are confined to the area north of the 60 Freeway on either side of Brea Canyon Road. The industrial uses are considered "light", no manufacturing or heavy machinery type uses are located within the City. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -E-3 Open Space Open space within the City of Diamond Bar is mostly scattered and limited in extent. However, there are four (4) large areas of vacant land left in the City: • West of the 57 Freeway, both north and south of Pathfinder and Brea Cutoff Roads (Sandstone Canyon, Pathfinder canyons, and Brea Cutoff canyons), • The south end of "The Country", a gate -guarded community in eastern Diamond Bar, • Between Leyland and Diamond Bar Boulevard, north of Grand Avenue (Upper Sycamore Canyon), and • The hills and valleys in the extreme northeast corner of Diamond Bar, south of the 60 Freeway, called Tres Hermanos. Additional open land is scattered along manufactured slopes and serves as buffer zones between conflicting land uses. A survey of potential development restrictions on various parcels of open land in the City Is provided in the Land Use Appendix. Recreation Recreational areas and neighborhood parks are distributed through the City. The most prominent recreational feature is the Diamond Bar Golf Course, located at Golden Springs and Grand Avenue (178 acres). Other significant recreational uses include Sycamore Canyon Park located adjacent to the Golf Course, and the Little League Field and Park located west of the 57 Freeway. A private park, tennis, and equestrian center is located in "The Country' development. In total, developed recreational uses total almost 60 acres, while there are 75 more acres in undeveloped parks. "The Country park occupies 186 acres, while the Little League fields occupy another 8 acres. k. Public Facilities Various public facilities available within the City include schools, city administration offices, Chamber of Commerce, public library, and police and fire protection facilities. The 8 elementary schools, 3 junior high or middle schools, and one senior high school in the City occupy approximately 180 acres. The City's public library is located on Grand Avenue between Golden Springs and Diamond Bar Boulevard. The City Hall and administration offices are located in the new Gateway Center. The City has two Los Angeles County fire stations within its boundaries. Transportation Facilities The dominant transportation features within the City are the Pomona (60) and Orange (57) freeways. The 57 Freeway travels along the western portion of the City in a north -south direction. The 60 Freeway merges with the 57 near the central portion of the City, then splits again to the east near the northern City limits. Together with major streets, these facilities occupy 787 acres within Diamond Bar. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -E-4 M. Other Uses Other major non-residential land uses include the Diamond Bar Golf Course (178 acres), schools (158 acres), and parks (109 acres). At present, there are 2,764 acres of vacant open land potentially available for development and/or preservation. The largest parcel of vacant land in Diamond Bar, except for the sphere of influence, Is the Tres Hermanos property, at the northeast corner of the City, between Grand Avenue and the 60 Freeway. n. Sphere Of Influence The City of Diamond..Bar's sphere of influence, as presently approved by the Los Angeles County Local Agency Formation Commission (LAFCO), encompasses 3,591 acres immediately south of the City limits to the Los Angeles/Oronge County border. This sphere area represents the middle portion of Tanner Canyon, an undeveloped northeast/southwest trending wooded canyon. This portion of the canyon is presently owned by the Boy Scouts of America and utilized for their Firestone Boy Scout Reservation. The Scout Reservation is an unimproved camping facility, and the only improved uses in the canyon are scattered campground support buildings, a water tower on the southern ridge, and a commercial radio tower on the northern ridge. There have been several studies for a regional roadway in Tonner Canyon. This roadway could start In the canyon on Grand Avenue, east of the Los Angeles/San Bernardino County line, and connect to the 57 freeway in Orange County near the City of Brea. Several other alignments have been proposed, however, that would move the road east, out of Tonner Canyon, into the Chino Hills development. Regional circulation studies indicate that Grand Avenue will experience a tremendous increase in commuter traffic as the areas east of the City develop. However, even with the construction of this connector roadway, traffic levels on Grand will still increase significantly as capacity on the new roadway is used up, probably within 5-10 years after it Is completed. Development of such a roadway would significantly impact the open space and biological resources of the canyon, although it would allow for more convenient access to Tonner Canyon from Diamond Bar itself, instead of having to use the Tonner Canyon interchange in Brea (Orange County). An arterial connection could also be added to allow access to Tonner Canyon from Diamond Bar Boulevard. o. Adjacent Land Uses The City is surrounded by the City of Industry, the City of Pomona, and unincorporated land within the counties of San Bernardino (Chino Hills) and Los Angeles (Rowland Heights). The following is a more detailed description of land uses adjacent to the City: South To the south, east of the 57 Freeway, Diamond Bar is bordered by unincorporated Los Angeles County land, Tonner Canyon/Firestone Boy Scout Reservation and the southwest is bordered by Los Angeles County unincorporated open land. Further to the south and southwest is the City of Brea in Orange County. West South of the 60 Freeway and west of Diamond Bar Boulevard is the community of Rowland Heights, while north of the 60 Freeway and east of the 57 Freeway are the cities of Industry and Walnut. The City of Industry is comprised mainly of light industrial, agriculture, and open land uses. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8,1 W2 II -E-5 North To the north are the college campuses of Mount San Antonio Community College (Mt. SAC) in Walnut, and the California State Polytechnic University at Pomona (Cal Poly Pomona) in Pomona. To the northeast is the City of Pomona, with the Lanterman State Hospital/Development Center located Immediately to the northwest of the City. East To the east of the City is a large planned community in unincorporated San Bernardino County known as Chino Hills. The majority of this land adjacent to the City is vacant, but it is under development with completion anticipated Into the next century. P. Potential Annexation Areas The sphere of influence presently occupies all of the available vacant land south of the City limits to the Los Angeles/Orange County line. The community of Chino Hills occupies all of the land to the east, Phillips Ranch and the City of Pomona occupy the lands to the north and northwest, while the City of Industry Is located along the western boundary of the City. The only vacant land adjacent to the City that is within Los Angeles County and is not already incorporated is approximately 4,100 acres (6.4 square miles) near the southwest corner of the City. This area is south of the unincorporated community of Rowland Heights, west of Lo Habra Heights, and north of the City of Brea in Orange County. Rowland Heights consists mainly of residential uses with commercial establishments along the 60 Freeway, while the vacant lands are comprised mainly of rolling hills used for cattle grazing. q. Views of the City Figure II -E-2 presents various views of the land and land uses of Diamond Bar. Yews are both in and around the City, including the sphere of influence (Tanner Canyon). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -E-6 Table II -E-1 City -Wide land Use (1990) Residential Subtotal EXISTING USES 17,664 100.0 RESIDENTIAL EXISTING USES PERCENT OF PERCENT OF NON-RESIDENTIAL < LAND USES ACRES UNITS RESIDENTIAL TOTAL ACRES Rural/Hillside 855.5 616 17.3 8.9 Single Family 3656.8 11,973 73.3 38.2 Multi -Family 440.1 5,075 8.9 4.6 Condominiums 350.2 4,132 7.1 3.7 Apartments 67.8 649 1.4 0.7 Mobile Homes 22.1 294 0.5 0.2 Residential Subtotal 4,952.4 17,664 100.0 51.7 EXISTING USES NON-RESIDENTIAL < PERCENT OF NON- PERCENT OF LAN p USES ... ACRES S9 FT. RESIDENTIAL TOTAL ACRES Commercial 181.8 1,901,000 9.7 1.9 Office 138.5 2,293,000 7.4 1.4 Business Park 83.6 1,165,000 4.5 0.9 Public Facilities 211.7 11.3 2.2 Parks/Recr/Open Space 464.2 24.9 0.5 Fwys/Major Roads 787.1 42.2 8.2 Non -Residential Subtotal 1,866.9 5,359,000 100.0 19.5 Vacant Land 2,763.7 0 28.8 TOTAL 9,583.0 100.0 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -E-7 5 0 41 Zi gUj W g W p5 Z Z o Z o /nn 1/7 / W V cc �U Z zKIw _ o N W Z O w 0 \ / \k }0 $k »@ 91 E 0 k e ƒ \ A E 0 9 Z CL/ 3 < $ / / \ ( — z 0 \ 2 / ( a _ \ / \k }0 $k »@ 91 E 0 k e ƒ \ A E 0 9 D n Z � T• LL V' C _ rP/ OfLU O / Z O Z O W U O Z = Uj � O N �5 0 91 E O 91 i d L E O Q ,C V � c O O vV CD L �r L o Z ami 3 L C) c 10 'A' ��- d L E O Q ,C V � c O O vV CD L �r L o Z ami 3 L C) c 10 V N Z .I .i L�sj'.s_.. ��• ��i'r ! Y J Q Q_ P• W `L/ N % OLU 0 Z Z O Z J 2 W F" � 2 V) O 3 O Z` A 9 0 a 3 O 0 ex .I .i L�sj'.s_.. ��• ��i'r 9 0 a 3 O 0 ex s Z J � Jw z (DE O Z o W o O Z LU � O N N L' ►`MWA 1 O O L U N L S Z' C O 7 m 0 �U G � O E O O 1. 0Q) O j L0 o a) Z L 3E o >Z= 0 LO � C O OU � L �r 0. 0 m-0 L C (1) L 3 o O N a) N L E L Q m m N Z - g < ' LU `n N 0 Z 0 0 _ LU CL L = z w U Z P. m 9 0— 2. ISSUES AND OPPORTUNITIES The City must face a variety of land use issues as it makes decisions about the ultimate disposition of land In Diamond Bar. The preservation of hillside open spaces is a major policy decision facing the City of Diamond Bar. There are several significant open or hillside areas left in the City, but they are under increasing pressure to develop. A major issue that must be addressed involves the status of restrictions against buildings previously approved by the County. Some of these open space areas were precluded from development as a condition of approval for on adjacent tract. Often, these areas were calculated as the open space requirement for the adjacent development, even though the County did not accept dedication. In some instances, additional density was granted to the adjacent development In exchange for retaining these areas as open space. These areas were often dedicated for environmental reasons, or because they had physical constraints and would create high maintenance costs to the County or high development costs to the owner. As land becomes more valuable (more costly) in Diamond Bar, these higher costs become less of a restriction to development. It can be expected that the City will be asked to reconsider development of some of these lands previously designated as open space. Whether or not these open space areas are allowed to develop is a policy issue for the City rather than a property right. Individual property owners with large, hillside lots may also wish to re -subdivide their lots and increase the number of allowable units. The individual property owner would reap an economic benefit, and more individuals would have access to hillside lots. However, there would be a decrease in the actual, and perceived, amount of open space that characterizes the community. The City may also choose to 'develop" several different forms of open space. For example, a tract might grade a slope to create a pad of homes and a recreation area. While the natural, passive open space area is lost, a man-made, active open space is created. In each case, the City must decide what type of open space best captures the community vision it wishes to create, while recognizing the interdependency of such factors as maintenance and fire protection costs. Another major issue facing the community is the preservation of existing neighborhoods, as long as they are of good quality, and represent a benefit to the community. In general, housing densities, types of units, and lot sizes should be maintained in established residential areas. However, the desire to maintain existing uses must be weighed against eliminating uses that are not compatible, or that are not appropriate for a specific area. Remedial action may range from eliminating or minimizing conflicts (walls to block freeway noise), to designating areas for more appropriate uses. One land use issue that will result from conscious decisions to maintain existing low density residential development will be the mandated provisions for affordable housing. One of the main reasons for incorporation of the City was a cumulative aversion to the increasing density of residential projects approved by the County (Highlander 1989). Yet, higher density projects help provide alternative housing types to serve a variety of housing and income needs for groups such as seniors, handicapped, single parent households, etc. Municipal financing is also closely tied to land use decisions. The amount and variety of non-residential (especially commercial) uses allowed in the City will largely define its revenue options as it determines the types of services it can provide for its residents. Aside from property taxes and per capita subventions, sales taxes are often the largest source of municipal revenues. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. t 992 II -E-15 The sphere of influence also represents a significant challenge to the City in terms of balancing the responsibility of protecting regional open space and biological resources versus the need for regional transportation solutions and development that could provide additional City revenues. The other major Issue regarding the sphere of influence Is a regional connector roadway. Although such as roadway would provide temporary relief in terms of traffic congestion within Diamond Bar, future traffic, generated by growth east of the City, will negate any long-term benefits. It is likely that traffic congestion would be back to existing levels within 5 years after opening the new roadway. However, it is possible to build such a roadway outside of Tonner Canyon to the east, within Chino Hills. This would provide traffic relief as well as help preserve the sensitive resources of Tonner Canyon. The City should also consider annexing some additional open lands along the west side of Brea Canyon Cutoff. The most likely areas are the canyons and ridges adjacent to Brea Cutoff and the 57 Freeway, around the Arciero Business Park. The natural slopes and canyons surrounding the Arciero project should be preserved, as well as the heavily wooded canyons along Brea Cutoff. Additional residential development could be planned for the ridges, while some freeway commercial development could be added near the on-off ramp areas. However, the City should NOT consider annexing any of the existing residential development west from the 57 Freeway over to Nogales in Rowland Heights. This area (west of the current City boundary) contains mainly residential uses and very little freeway commercial uses that could be self-supporting In terms of City finances. This area is also within the probable incorporation boundaries of Rowland Heights, and the los Angeles County Local Agency Formation Commission has previously denied the City inclusion of this area into its sphere of influence. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .June 8, 1992 II -E-16 F. Alla QUALITY 1. EwsnNG SEmNG Air quality throughout the Los Angeles basin is considered the worst in the nation. Since Diamond Bar is part of the Los Angeles basin, its air quality Is also poor, mainly from sources outside of the City. Diamond Bar's air quality is the result of the regional and local weather acting on air pollutants produced locally, as well as within the los Angeles basin, and the movement (or lack of movement) of air pollution out of the area. a. Climate Southern California's climate Is characterized as Mediterranean with warm summers and mild winters, Infrequent rainfall, and moderate daytime onshore breezes. Temperatures in Diamond Bar range from 50 to 90 degrees Fahrenheit (°F) in summer and from 40 to 80 OF in winter. The average annual low in winter is 39 OF, while highs in the summer average 88 OF. The average annual mean temperature in Diamond Bar is a comfortable 62.5 OF. Precipitation comes mainly from Pacific storms that pass through the area during the winter and spring (November through Aprin. Annual rainfall in the East San Gabriel Valley varies from 7 to 20 Inches, with a long term annual average of about 10.8 inches per year. Although climatic conditions make the Southern California region desirable, a semi-permanent high pressure center over the Pacific Ocean severely restricts the movement of air, and thus the dispersion of pollutants, out of the Los Angeles (South Coast) air basin. b. Wind Patterns Prevailing breezes are towards the northeast at an annual average of about 12 miles per hour (mph). During the daytime, winds tend to blow north and east through the local passes, reversing themselves at night. In the summertime, winds move across the nearby San Gabriel Valley at 5-13 mph during the day, but slow to 3-6 mph at night. During the winter, this daily reversal is not as pronounced, with daily breezes of 5-8 mph compared to 5-6 mph at night. During certain times of the year, strong dry desert winds, called Santa Anas, blow out of the west. These winds can cause periods of blowing dust and can temporarily push local pollutants out of the east San Gabriel Valley. While air movement through the basin is generally adequate to flush daily air pollutants, air can stagnate due to a variety of conditions caused by the basin's location and shape. C. Air Pollutant Movement The location of a semi -desert basin (Los Angeles) so close to the Pacific Ocean creates two distinct air pressure systems that govern regional air movement. Daily and annual air temperatures of the on -shore (over land) system vary considerably, while temperatures over the off -shore (over the ocean) system stay more constant. These temperature differences create the two distinct air pressure systems which in turn govern the regional transport of air pollutants. During much of the year, air pollutants created in the South Coast Air Basin are moved out of the basin through mountain passes by regional winds, or are lifted over the mountains by rising air currents. In this manner, the air basin is cleansed by natural air movement. During the summer months, lighter winds and a shallow vertical mixing layer combine to reduce or prevent the dispersion of air pollutants. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSES MENT June 8. 1992 II -F-1 The complex Interaction of the two air pressure systems create two different types of temperature 'inversions' that hinder the regional movement of air pollutants. Their complex interactions govern the vertical depth through which pollutants are mixed. The onshore flow is topped by a massive dome of warm, sinking air which caps a shallow layer of cooler ocean air. These marine Inversions act like a giant lid over the basin. They allow for local mixing of emissions, but they confine the entire polluted air mass within the basin until it escapes into the desert or along the thermal chimneys formed along heated mountain slopes. During winter months, the air near the ground cools while the air aloft remains warm, forming radiation Inversions that trap low-level emissions such as automobile exhaust near their source. As vehicular exhaust rises during the seaward return flow, the combination of base line levels plus emissions trapped locally by radiation inversions create microscale air pollution near freeways, shopping centers, and other traffic concentrations In coastal areas of the Los Angeles Basin. While inland valleys experience poor periods of air quality on summer afternoons during strong onshore wind conditions, winter mornings are the periods of poorest air quality in coastal areas during strong offshore flow. To further exacerbate the problem, the east San Gabriel Valley receives polluted air from neighboring areas In addition to the pollution it produces locally. This valley is situated in a area where air pollutants undergo photochemical reactions in the presence of sunlight, and then move during the daily sea breeze cycle. The prevailing winds usually transport pollutants generated in the morning in the Los Angeles area, which travel toward Diamond Bar, undergoing photochemical reactions along the way. The air that finally reaches Diamond Bar is quite 'developed', that is, it contains air pollutants that were formed as it traveled. These conditions produce very poor air quality, involving a number of air pollutants, throughout the entire South Coast Air Basin. d. Air Pollutants Major air pollutants include both primary pollutants (those produced directly from pollutant sources) and secondary pollutants (those that result from photochemical reactions between primary pollutants and sunlight). Primary pollutants include carbon monoxide, hydrocarbons, oxides of nitrogen, sulphur dioxide, and particulates. Secondary pollutants include oxidants, of which ozone is the most prominent. The following are the contaminants of major concern, most of which are associated with vehicular exhaust and photochemical smog: • Carbon Monoxide (CO) This odorless, invisible gas is primarily produced by vehicle exhaust. It interferes with the oxygen transfer process in blood hemoglobin and can cause dizziness, nausea, and can be toxic to humans when concentrated in enclosed places. Carbon monoxide is a prime contributor to the production of other (secondary) pollutants through photochemical reaction. • Hydrocarbons (HC) These pollutants include a variety of hydrogen and carbon compounds from vehicular exhaust, but also many individual sources such as dry-cleaning stores, points, and fuel evaporation. • Oxides of Nitrogen (NOx) These pollutants result largely for the incomplete oxidation of fuel in vehicular engines. They can combine with other pollutants in the presence of sunlight to form other (secondary) pollutants of which Nitrogen Dioxide (NO2) is the primary constituent. • Nitrogen Dioxide (NO2 This brownish gas results from the photochemical reaction of oxides of nitrogen in the presence of sunlight. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL AsSESMENT June 8, 1992 II -F-2 • Particulates (Part) These are small airborne particles from various sources including Internal combustion engines (both diesel and gasoline powered). The particles of most concern are aerosols and particles of 10 microns or smaller (PM1� which con penetrate deep into and cause damage to lung tissues. • Sulphur Dioxide (SO.) This pollutant is produced mainly from power plants and certain large industrial plants such as oil refineries. This yellowish gas can irritate mucous membranes. • Ozone (03) Ozone constitutes 90 percent of all oxidating air pollutant compounds (oxidants) that can irritate mucous membranes and breathing passages. It is produced by a photochemical reaction with ultraviolet radiation in sunlight and primary pollutants such as carbon monoxide, hydrocarbons, and oxides of nitrogen. e. Air Pollutant Monitoring The South Coast Air Quality Management District (SCAQMD) monitors ambient air quality data in terms of State and federal standards. These standards have been adopted to minimize the risk for that segment of the population susceptible to respiratory response. In addition to federal standards, California has adopted episode criteria for oxidant, carbon monoxide, and sulfur dioxide. The episode levels are defined as short-term exposures at which public health Is actually threatened. Diamond Bar is located within Source Receptor Area # 10 of the South Coast Air Basin, and the SCAQMD maintains a monitoring station for this area in the City of Pomona. Table II -F-1 presents the most recent air quality data collected from this station, which is only equipped to monitor carbon monoxide, ozone (oxidants), and nitrogen dioxide. Basin -wide, it should be noted that actual concentrations of the most significant air pollutant, ozone, has been decreasing slowly over the past decade, which is borne out by the historical air monitoring data presented in Table II -F-2. Ambient Air Quality During 1988, the federal oxidant standard (0.12 parts per million or ppm in 1 hour) was exceeded on 91 days at the Pomona station, while State standard (0.10 ppm) was exceeded on 145 days. During this some period, the maximum one hour concentration of ozone was 0.29 parts per million (PPM). However, nitrogen dioxide concentrations were found to be within the federal standard with no days exceeding State or federal standards. A review of neighboring receptor areas also indicates that ozone is the principle pollutant of concern. Figure II -F-1 shows historical exceedance days for the Pomona station. A historical record of ozone and nitrogen dioxide concentrations (the two air pollutants of most concern) is shown in Table 11-F-2. This data shows that the current maximum ozone concentrations have decreased by 18-25 percent (compared to the average and median values) over the past ten years (1978-1988). The number of days that ozone levels exceeded the federal standard also decreased, although the number of days exceeding the State standard show a smaller, but still significant decrease. Historical nitrogen oxide levels do not show a significant decrease compared to historical levels or to ozone levels. However, the concentrations of this pollutant are already lower than either the State or federal standard. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESMENT June 8, 1992 II -17-3 Table I -F-1 Local Air Quality (Pomona Station) Maximum - Days Concentration Exceeded (PPM) PoIlWantl Standard 1989 1990 1989 1990 Carbon Monoxide (CO) Federal z 9.5 PPM 0 0 -- -- 8 Hours Federal > 35 PPM 0 0 12.0 13.0 1 Hour State >- 9.1 PPM 0 0 -- -- 8 Hours State > 20 PPM 0 0 12.0 13.0 1 Hour e�-- •.• - Federal > .12 PPM 61 60 0.25 0.24 1 Hour State >:.09 PPM 117 104 0.25 0.24 1 Hour Nitrogen Dioxide (NO2) State > .25 PPM 1 0 0.26 0.21 1 Hour Source: '1989 and 1990 Air Quality Data Sheets,' South Coast Air Quallty Management District. Sulfur Dioxide, Suspended Particulates, Lead, and Sulfate not measured at Pomona Station. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASS ESM ENT June 8, 1992 II -F-4 Table I1- -F-2 Historical Air Pollution) 10 -Year Average Maximum Federal -Days State -Days Pollutant Year Concentration Exceeded Exceeded OZONE 1990 0.25 60 104 1989 0.24 61 117 1988 0.29 91 145 1987 0.29 72 122 1986 0.27 89 133 1985 0.33 98 138 1984 0.31 98 138 1983 0.34 102 135 1982 0.35 100 136 1981 0.33 97 137 1980 0.37 99 140 10 -Year Average 0.31 88 131 Median 0.31 97 136 NITROGEN DIOXIDE 1990 0.24 0 1989 0.26 1 1988 0.20 0 1987 0.22 0 1986 0.25 1 1985 0.23 0 1984 0.20 0 1983 0.21 0 1982 0.28 3 1981 0.31 5 1980 0.27 1 10 -Year Average 0.24 1 Median 0.23 0 Source: 11978-1989 AJr Quality Data Sheets', South Coast Air Quality Management Agency. 1 One-hour measurements in parts per million. len-year period is 1980-1990. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESMENT June 8, 1992 II -F-5 0 O Ix LU m z J Q z z Q 1U 15( 10C 50 1 m POMONA STATION FIGURE II -F-1 1--- ANNUAL DAYS EXCEEDING STATE OZONE STANDARD f --ANNUAL DAYS EXCEEDING FEDERAL. OZONE STAN DAR D 1981 1982 1983 1984 1985 1986 1987 1988 YEARS HISTORICAL OZONE LEVELS SOURCE:_err Air Quality Data Table, 1980-88; Southern California Air Quality Management District, FTI= 11111111 LAN N I NG N EPWORK GENERAL PLAN Air Pollutants CO ROG NOx Particulates NOx OXIDES of NITROGEN LANN I NG NETVIORK NOTE: Typical suburban development project emissions. Percent totals are separate for mobile and stationary sources. (Planning Network, 1989). II -F-2 AIR POLLUTANT GENERATION BREAKDOWN DIAMOND HAFT . , gig- �i MOBILE SOURCE STATIONARY SOURCE CO CARBON MONOXIDE ROG REACTIVE ORGANIC GASES NOx OXIDES of NITROGEN LANN I NG NETVIORK NOTE: Typical suburban development project emissions. Percent totals are separate for mobile and stationary sources. (Planning Network, 1989). II -F-2 AIR POLLUTANT GENERATION BREAKDOWN DIAMOND HAFT . , gig- �i g. Local Sources and Sensitive Receptors The City of Diamond Bar is not only affected by regional air pollution but also generates its proportionate share of pollutants. Although local pollutants are generated by a number of stationary and mobile sources, the majority are generated by vehicular exhaust from mobile sources. Certain segments of the local population who are especially sensitive to poor air quality include young children, the sick, and the elderly; these groups are referred to as "sensitive receptors". Facilities that contain sensitive receptors include schools, child-care centers, hospitals, and convalescent facilities. The locations of sensitive receptors in the City are shown in Figure II -F-3 and described .in Table II-F�3. Some of these receptors are adjacent to roadways with high traffic volumes and may experience elevated levels of air pollutants due to the localized concentration of vehicular exhaust (such as at intersections when vehicles idle waiting for traffic lights). h. Air Quality Management Plan The current Air Quality Management Plan (AQMP) for the South Coast Air Basin was adopted by the California Air Resources Board in 1989. This document establishes policy designed to meet and maintain federal and State ambient air standards by 1995. Local cities and counties are encouraged to review "significant" proposed development projects based on the new AQMP. Projects are considered "significant" (in size only) if their total projected emissions exceed certain threshold criteria. The determination of environmental significance of project Impacts is still determined by the Lead Agency during the CEQA process. Cities are now strongly encouraged to "conform" to the AQMP in their General Plans. This can be done as an optional (separate) Air Quality Element or as part of the Circulation and Open Space and Conservation Elements, or by incorporating the implementation programs at the AQMD into the General Plan. These programs are included in the Air Quality Appendix. The AQMP suggests implementation measures to help cities and counties attain the regional air quality goals. This implementation plan contains over 75 control measures which may affect most residents and businesses in the air basin at some point. Cities are also encouraged to develop, implement, and monitor their own policies to achieve the goals of the AQMP. These include, but are not limited to carpooling, vanpooling, alternative fuels, modified work hours, public transit, etc. Additional information on State Implementation Plan (SIP) guidelines for "conformity" or local General Plans to the AQMP is provided in two reports published by the Southern California Association of Governments (SCAG) in March of 1990; "Guidelines for the Development of Local Air Quality Elements", and "Guidance for Implementation of 1989 AQMP Conformity Procedures." CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESMENT June 8. 1992 II -F-8 Table 11-F-3 Sensitive Receptors in Diamond Bar 1 Map Ret SeWive Receptor 2 Address 13 Public Schools WVUSD) 22600 Sunset Crossing Road 1 Castle Rock Elementary 2975 Castle Rock Road 2 Evergreen Elementary 2450 Evergreen Springs Road 3 Maple Hills Elementary 1350 Maple Hill Road 4 Quail Summit Elementary 23330 Quail Summit Drive 5 Walnut Elementary 841 Glenwick 6 Chaparral Middle 1405 Spruce Tree Drive 7 South Pointe Middle 20671 Larkstone Drive 8 Diamond Bar High 21400 Pathfinder Road 22 Public Schools (PLISD) 801 Brea Canyon Road 9 Armstrong Elementary 22750 Beaverhead Drive 10 Diamond Point Elementary 24150 Sunset Crossing Road 11 Golden Springs Elementary 245 S. Bollena Drive 12 Lorbeer Junior High 501 Diamond Bar Boulevard Private SchooWPre-SchooWChild Care Centers 13 YMCA Child Care Center 22600 Sunset Crossing Road 14 IGnder Care Learning Center 23555 Palomino Drive 15 Mount Calvary Pre -School 23300 Golden Springs Drive 16 Diamond Bar Community Nursery School 400 Rancheria Drive 17 Village Montessori Academy 23431 Golden Springs Drive 18 Maple Hill Tiny Tots Pre -School 1673 Maple Hill Road 19 Diamond Bar Children Center 2335 Diamond Bar Boulevard 20 La Petite Pre -School 21385 Cold Springs Lane 21 Peppertree Child Enrichment Center 3201 S. Brea Canyon Road 22 New Horizons Learning Center 801 Brea Canyon Road 1 Ma numbers refer to Figure II -F•3. Sensitive receptor locations are Lased on C and P 9 P fly phone company records including public and private schools, pre-schools, and child care centers; there are no hospital, convalescent, or retirement facilities within the City. 2 Walnut Valley Unified School District (MUSD) and Pomona Unified School District (PUSD). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL A S S E S M E N T June S. 1992 II -F-9 (n ov W CL. W �/lRW Wzd Ws�4Z1 W Z V.0 Oy CL ix .n-vo.0-^ O P N a -RNCR 0 0 F g A ccW CL w (n ov W CL. W �/lRW Wzd Ws�4Z1 W Z V.0 Oy CL ix .n-vo.0-^ O P N a -RNCR 0 0 F g 2. ISSUES AND OPPORTUNITIES Although local vehicular traffic and land uses in Diamond Bar do generate air pollutants, the contribution of air pollutants from Diamond Bar are less than one percent of the total air basin. Therefore, actions to reduce the production of air pollutants will only have an incremental effect on regional air pollution. Coordinated regional programs are therefore the best method of reducing regional air pollution. The City will work with the South Coast Air Quality Management District (SCAQMD) and the Southern California Association of Governments (SCAG) In the coming years to Implement applicable sections of the Air Quality Management Plan (AQMP), as amended. A major advantage for the City in this regard will be the relocation of the SCAQMD main office to Diamond Bar. Vehicles account for over 90 percent of major air pollutants in this air basin. The two most plentiful primary pollutants are carbon monoxide and nitrogen oxides (85 percent) and are both produced mainly from vehicular sources. Therefore, the most effective ways of reducing local and regional air pollution are those actions which reduce vehicle use, either by reducing the total number of trips generated, or by reducing the average distance of the trips. Since the vast majority of pollutants come from vehicular exhaust, emphasis should be placed on programs that reduce the number or length of individual trips, such as ridesharing or utilizing public transit. Many cities are also requiring Transportation System Management (TSM) plans from new employers and businesses. A number of businesses in the Orange County area have responded by forming a Transportation Management Agency or Organization (TMO/TMA). The City shall also consider a telecommuting office building or studio within the Gateway Corporate Center, which would help reduce some commute trips by both residents and non-residents. Caltrans already maintains two Park and Ride facilities adjacent or within the City. Since it is at the intersection of two major Los Angeles basin freeways, Caltrans may want additional Park and Ride locations, although they would not necessarily have to be located in Diamond Bar. However, they should be located where they would be convenient for City residents. In addition to Implementing those programs and actions required by law, the City should decide tf it wants more stringent and/or diversified policies, ordinances, etc. to address minimizing air pollutants generated by City_ residents and activities. For example, a policy encouraging the installation of solar energy equipment will help reduce utility energy consumption and thus reduce regional air pollution. During its determination on appropriate City policies regarding air quality, a balance must be achieved between regional air quality goals and local goals and policies of the City. For example, SCAG is emphasizing a regional balance of jobs to housing to help reduce vehicular exhaust produced by long commuter trips. Cities that have a deficit of jobs, or an overabundance of housing by SCAG standards, may feel pressured into adopting or give higher priority to processing non-residential projects. Another example would be increased housing costs caused by adopting a strict a new solar energy ordinance. Such action could conflict with the City's ability to provide affordable housing, as well as the Regional Housing Needs Assessment by SCAG. Such actions could conflict with the City's goals relative to maintaining a rural residential community. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL AssEsMENT .lune 8, 1992 II -F-11 G. NOISE ExIsnNG SETTING a. General Plan legislation Adoption of a Noise Element has been a requirement of local General Plans since 1971. Section 65302 (g) of the California Government Code requires: 'A noise element which shall identify and appraise noise problems in the community. The noise element shall recognize the guidelines established by the Office of Noise Control in the State Department of Health Services and shall analyze and quantify, to the extent practicable, as determined by the legislative body, current and projected noise levels...' Current and projected noise levels are required for several sources including highways and freeways, local streets and primary arterials, railroad operations, airport operations, local industrial plants, and other ground stationary noise sources. State Legislative guidelines regarding the preparation of a Noise Element were amended in 1985. The primary change was the methodology for developing noise contours. A noise contour, which is similar to a topographic contour, maps a concentric 'footprint' around the noise source. The legislation now permits the use of either noise monitoring or approved methods of noise modeling in preparing noise contours. Both types of analysis were utilized in the preparation of this element. Stationary sources were monitored while vehicular noise was modeled. b. Characteristics of Noise Noise is a serious environmental problem which can cause adverse effects on the health and well being of people when exposed to various levels and sources of noise on a daily basis. The negative effects can be both physical and psychological. Loud noise over an extended period of time can cause temporary, or in some cases permanent, loss of hearing. Noise can also interfere with communication, sleep, cause irritability, increase fatigue, and cause the inability to concentrate. Noise can decrease a child's ability to concentrate, as well as decrease a child's ability to discriminate among different sounds, both of which affect learning ability. Noise is defined as unwanted or harmful sound, and has three important physical characteristics: Amplitude/Loudness is the sound pressure measured in decibels (dB). Decibels are based on a logarithmic scale; due to the extensive range of sound intensities it is necessary to compress the scale to encompass all the sounds needed to be measured. Frequency/Pitch is measured in Hertz (Hz), which is the measurement of sound source vibrations or the rate at which air vibrates. Pattern of time can be broken into three separate categories, continuous, intermittent, and fluctuating. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-1 (1) Definitions In discussing noise and its impacts, specific terms are used, these terms ore described below: Decibel, dB: A unit of measurement describing the amplitude of sound, equal to 20 times the logarithm to the base 10 of the ratio of the pressure of the sound measured to the reference pressure, which is 20 micropascals (20 micronewtons per square meter). A-Welghted Level: The sound level is decibels as measured on a sound level meter using the A -weighing filter network. The A -weighing filter deemphosizes the very low and very high frequency components of the sound in a manner similar to the response of the human ear and gives good correlation with subjective reactions to noise. Leq: Equivalent energy level. The sound level corresponding to a steady state sound level containing the some total energy as a time varying signal over a given sample period. Leq is typically computer over 1, 8, and 24-hour sample periods. CNEL: Community Noise Equivalent Level. The average equivalent A -weighted sound level during a 24-hour day, obtained offer addition of five decibels to sound levels in the evening from 7 p.m. to 10 p.m. and offer addition to 10 decibels to sound levels in the night from 10 p.m. to 7 a.m. Ldn: Day -Night Average Level. The average equivalent A -weighted sound level during a 24-hour day, obtained offer addition of 10 decibels to sound levels in the night after 10 p.m. and before 7 a.m. Note: CNEL and Ldn represent daily levels of noise exposure averaged on an annual or daily basis, while Leq represents the equivalent energy noise exposure for a shorter time period, typically one hour. Noise Contours: Lines drawn about a noise source indicating equal levels of noise exposure. CNEL and Ldn are the metrics utilized herein to describe annoyance due to noise and to establish land use planning criteria for noise. Ambient Noise: The composite of noise from all sources near and far. In this context, the ambient noise level constitutes the normal or existing level of environmental noise at a given location. Intrusive Noise: That noise which intrudes over and above the existing ambient noise of a given location. The relative intrusiveness of a sound depends upon its amplitude, duration, frequency, and time of occurrence, and tonal or informational content as well as the prevailing noise level. (2) Measurement of Sound In order to quantify the noise environment, it is necessary to differentiate between measurement of individual sounds and continuous sounds. Individual sounds are measured by air pressure and can be expressed in decibels (dB). The A -weighted decibel scale (dbA) is most often used to assess potential impacts to human health and safety. The A scale de-emphasizes the very low and very high frequency components, and places a greater emphasis on sound frequencies within the sensitivity range of the human ear. Everyday sounds normally range from 30 dBA (very quiet) to 100 dBA (very loud). The average level of conversation ranges from 55 to 80 dBA. Sound becomes discomforting at 120 dBA, and physically painful at 140 dBA. Figure II -G-1 presents a range of typical noises._ Background noise affects speech communication at approximately 70 dBA, and becomes increasingly difficult at 90 dBA. Figure II -G-2 shows how noise interferes with conversational speech. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1 992 II -G-2 Continuous sounds require an additional method of description. Equivalent Noise Level (Leq) Is a common noise rating scale. h is the energy average of fluctuating noise source over a specified period of time. The energy average (Lq) of each hour of the day, weighted for the more sensitive time periods within 24 hours, may describe the Community Noise Equivalent Level (CNEL) or day -night average "level Day -Night" (Ldn)- California Planning and Zoning Law, Section 65302 (f) requires that general plan noise elements use either CNEL or Ldn to describe and evaluate community noise levels. The 1983 Diamond Bar Community General Plan used the Ldn method to evaluate noise within the City. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -G-3 Physically Painful Extremely Loud Discomforting Very Loud Loud Quiet Threshold of Hearing SOURCE: Endo Engineering, 1990. LANN ING NEMOW dBA FIGURE II -G-1 Sonic Boom Jet Takeoff at 200' Oxygen Torch Discotheque Motorcycle at 15' (Unmuffled) Power Mower at 3' Newspaper Press Freight Train at 50' Food Blender Electric Mixer, Alarm Clock Heavy Truck at 50' Busy Street Traffic at 50' Average Traffic at 100', Vacuum Cleaner at 10' Electric Typewriter at 10' Dishwasher at 10', Air Conditioning Unit at 15' Normal Conversation at 5' Typical Daytime Suburban Background Refrigerator at 10' Bird Calls Library Motion Picture Studio Leaves Rustling LOCAL NOISE LEVELS GENERAL PLAN FIGURE II -G-2 a m a 0 J N f 0 z a c 0 Y U M E 5 3 0 J 4 U 5 1U 15 20 25 30 Talker to Listener Distance in Feet NOISE INTERFERENCE WITH SPEECH SOURCE: Miller, 'Effects of Noise on People', Journal of Acoustical Society of America, V. 56, No. 3, September, 1914; and''Endo Engineering. 1990. LAN N I NG N ERVORK GENERAL PLAN (3) Land Use Compatibility Guidelines The purpose of this section is to present information regarding the compatibility of various land uses with environmental noise. It Is from these guidelines and standards that the City of Diamond Bar Noise criteria and standards will be developed. Nolse/land use guidelines have been produced by a number of Federal and State agencies including the Federal Highway Administration, the Environmental Protection Agency, and the State of California. These guidelines, presented in the following paragraphs, are all based upon cumulative noise criteria such as LE9, LDN or CNEL. The U.S. ENVIRONMENTAL PROTECTION AGENCY (EPA) published In March 1974 a document entitled "Information on Levels of Environmental Noise Requisite to Protect Public Health and Welfare With and Adequate Margin of Safety: (EPA 550/9-74-004). Table II -G-1 presents a table of land uses and requisite noise levels. In this table, 55 LDN is described as the requisite level with an adequate margin of safety for areas with outdoor uses; this Includes residences and recreational areas. The EPA "levels document" does not constitute a standard, specification or regulation, but identifies safe levels of environmental noise exposure without consideration for economic cost for achieving these levels. The FEDERAL HIGHWAY ADMINISTRATION (FHWA) has adopted and published noise abatement criteria for highway construction projects. The noise abatement criteria specified by the FHWA are presented in Table II -G-2 in terms of the maximum one-hour Noise Equivalent Level (LE9). The FHWA noise abatement criteria basically establishes an exterior noise goal for residential land uses of 67 LE9 and an interior goal for residences of 52 LE9. The noise abatement criteria applies to private yard areas and assumes that typical wood frame homes with windows open provide 10 dB noise reduction (outdoor to indoor) and 20 dB noise reduction with windows closed. The STATE OF CALIFORNIA requires each city and county to adopt Noise Elements or the equivalent in their General Plans. Such Noise Elements must contain a noise/land use compatibility matrix. A recommended (but not mandatory) matrix is presented in the "Guidelines for the Preparation and Content of Noise Elements of the General Plan," (Office of Noise Control, California Department of Health, February 1976). Figure II -G-3 presents this recommended matrix. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .lune a. 1992 II -G-6 TABLE OF CONTENTS I. IMRODUCTION A. PURPOSE OF THE GENERAL PLAN .................................. 1-1 B. THE EXISTING SETTING REPORT .................................... 1-1 C. LOCATION ................................................. 1-1 D. CITY HISTORY ................................................ 1-3 E. CIRCULATION ............................................... 1-3 F. CITY CHARACTERISTICS ........................................ 1-4 G. SPHERE OF INFLUENCE ......................................... 1-4 H. DOCUMENT FORMAT ......................................... 1-5 N. EXISTING SETTING* A. LANDFORMS AND TOPOGRAPHY ................................ II -A-1 B. EARTH RESOURCES AND SEISMICITY .............................. II -B-1 - C. DRAINAGE AND FLOOD CONTROL .............................. II -C-1 D. BIOLOGICAL RESOURCES ..................................... II -D-1 E. LAND USE ................................................ II -E-1 F. AIR QUALITY .............................................. II -F-1 G. NOISE ................................................... II -G-1 H. CULTURAL RESOURCES ....................................... II -H-1 I. SOCIOECONOMICS .......................................... II -1-1 J. CRIME AND PREVENTION SERVICES .............................. II -J-1 K. FIRE HAZARDS AND PROTECTIVE SERVICES ......................... II -K-1 L. HEALTH AND EMERGENCY SERVICES ............................. II -L-1 M. HAZARDOUS MATERIALS ...................................... II -M-1 N. RECREATION AND OPEN SPACE ................................ II -N-1 O. EDUCATIONAL SERVICES ...................................... II -0-1 - P. WATER .................................................. II -P-1 Q. WASTEWATER ............................................. II -9-1 R. SOLID WASTE .............................................. II -R-1 S. ENERGY SYSTEMS .......................................... II -S-1 T. CIRCULATION AND TRANSPORTATION ............................. II -T-1 III. ADDRIONAL MATERIALS A. PERSONS CONTACTED ........................................ III -1 B. BIBLIOGRAPHY .............................................. III -5 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 1 Table ((-G-1 Environmental Protection Agency Guidelines Source: U.S. Environmental Protection Agency WX--f N a. Since different types of activities appear to be associated with different levels, Identification of a maximum level for activity Interference may be difficult except in those circumstances where speech communication is a critical activity. b. Based on lowest level C. Based only on hearing loss. d. An Leq (8) of 75 dB may be Identified in these situations so long as the exposure over the remaining 16 hours per day Is low enough to result in a negligible contribution to the 24-hour average, i.e., no greater than an Leq of 60 dB. Note: Explanation of Identified level for hearing loss. The exposure period which result in hearing loss at the Identified level is a period of 40 years. e Refers to energy rather than arithmetic averages. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-7 Indoor Ouldoor To Protect Nearing To Protect Nearing Against Activity Loss Against Both Activity Loss Both Land Use Measures interference Consideration Effects (b) Interference Consideration Effects (b) Residential with Outside Space and Ldn 45 45 55 55 Farm Residences Leq(24) 70 70 Residential with No Outside Space Ldn 45 45 Leq (24) 70 Commercial Leq (24) (a) 70 70 (c) (a) 70 70 (c) Inside Transportation Leq (24) (a) 70 (a) Industrial Leq (24)(d) (a) 70 70 (c) (a) 70 70 (c) Hospitals Ldn 45 a 45 55 55 Leq (24) 70 70 Educational Leq (24) 45 45 55 55 Leq (24)(d) 70 70 Recreational Areas Leq (24) (a) 70 70 (c) (a) 70 70 (c) Farm Land and General Leq (24) (a) 70 70 (c) Unpopulated Land Source: U.S. Environmental Protection Agency WX--f N a. Since different types of activities appear to be associated with different levels, Identification of a maximum level for activity Interference may be difficult except in those circumstances where speech communication is a critical activity. b. Based on lowest level C. Based only on hearing loss. d. An Leq (8) of 75 dB may be Identified in these situations so long as the exposure over the remaining 16 hours per day Is low enough to result in a negligible contribution to the 24-hour average, i.e., no greater than an Leq of 60 dB. Note: Explanation of Identified level for hearing loss. The exposure period which result in hearing loss at the Identified level is a period of 40 years. e Refers to energy rather than arithmetic averages. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-7 Table IF -G-2 FHWA Noise Abatement Criteria Activity Design Noise Description of Activity Category Category Level - Leq A 57 Tracts of land in which serenity and quiet are of (Exterior) extraordinary significance and serve an Important public need and where the preservation of those qualities is essential if the area is to continue to serve its intended purpose. Such areas could include amphitheaters, particular parks or portions of open spaces, or historic districts which are dedicated or recognized by appropriate local officials for activities requiring special qualities of serenity and quiet. B 67 Picnic areas, recreation areas, playgrounds, active sports (Exterior) areas and parks which are not included In Category A and residences, motels, hotels, public meeting rooms, schools, churches, libraries, and hospitals. C 72 (Exterior) Developed lands, properties, or activities not included in Category A or B above. D _ For requirements of undeveloped lands see paragraphs Ila and c in Federal Highway Administrations Program 7-7-3. E 52 Residences, motels, hotels, public meeting rooms, schools, (Interior) churches, libraries, hospitals, and auditoriums. Source: Federal Highway Administrations Program Manual FHPM 7.7-3. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1 W2 II -G-8 FIGURE II -G-3 LAND USE CATEGORIES COMMUNITY NOISE EQUIVALENT LEVEL CNEL CATEGORIES - USES <SS so tis 70 75 BOs RESIDENTIAL Single Family, Duple,L A A B B C D D Muhtple Family RESIDENTIAL Mobil• Hone A A B C C D D COMMERCIAL Hotel sfotel, Transient Lodging A A B B C C D Regionel.District COMMERCLAL Commercial Retail. Bank. Restaurant A A A A B B C Regional Vdlage MoAs Tfeaces District. soecial COMMERCIAL Office Budding. Researm and Industrial DevelopmenL Professional Offius, A A A B B C D InstL tbruti City Offices Building, COMMERCIAL Ampiosatr•.Cor"nHall Recreation B B C C D D D INSTfMIONAL Auditorium, Meeting Hal CIVIC CMIer Cfnbrens Amusement Park, "Nature GOMMERCUL Goal Cow". Go-cart Tract. A A A B B D D Reaeadon Equestrian Center. Spore flub COAAMERCIAL Auasmobile Service Station. Auto General, Special Dealership. Manufacturing. A A A A B B B INDUSTRIAL, WSTRUTIONAL Warehowing, Wholesale, Utilities lJSTITUTItONAL Hospital. Church, Library, Sdods' A A B C C D D General Clawoom OPEN SPACE Parks A A A B C D D Goll Coupe, Cemeteries, Nature OPEN SPACE Centers, Wildlife Reserves, Wildlife A A A A B C C Habitat AGRICULTURE Agricrltu• A A A A A A A INTERPRETATION ZONE A Specified I" use is satisfactory, based upon to assumption that any, buildings inwlved are of normal CLEARLY COMPATIBLE Conventional Construction without arty special noise insulation requirements. New construction or developm+•nt should be undertaken only after detailed anajrsis of the noise -ZONE 8 reduction requirements are made and needed noise insulation features in the design are determined. NORMALLY COMPATIBLE Conventional construction, with closed windows and fresh air supply systems or air conditioning will normally suffice. ZONE C New str conxbon or development should generally be discouraged. If now construcion or development NORMALLY INCOMPATIBLE does Proceed, a detailed analysis of noise reduction requirements must be made and needed mdse insulation features included in to design. ZONE D New construction or development should generally rot be undertaken CLEARLY INCOMPATIBLE LAND USE COMPATIBILITY WITH NOISE SOURCE: California Office of Planning Research (OPR) CANNING NEfVvORK I DIAMOND BAR �. C. Existing Noise Environment (1) Noise Generation Noise is generated from numerous sources in typical suburban settings like Diamond Bar. For the purpose of this report, the two major categories of noise sources are mobile and stationary. The most pervasive noise in Diamond Bar, as in most other communities, comes from mobile noise sources, Including motor vehicles and railroads. While the vehicles that utilize the roadways or tracks are mobile, the actual location or alignment of the noise source (i.e. track or road) is actually linear. Figure II -G-4 shows typical noise levels adjacent to railroads. Figure II -G-5 illustrates historical noise sources within the City in relation to noise sensitive uses. (2) Mobile Noise Sources A detailed noise analysis of existing local roadways was prepared by Endo Engineering in July of 1991. Table II -G-3 summarizes the results of the Endo survey. According to the 1991 Endo study, the following are the primary noise sources within Diamond Bar: The Orange (57) and Pomona (60) freeways, particularly in those areas adjacent to the freeways and along the "unbuffered" hillsides. Several major arterial roadways which generate significant noise levels within the City: - Diamond Bar Boulevard (several locations at 66 dB) - Colima Rood/Golden Springs Drive (66.5 dB near Lemon Avenue) - Grand Avenue (65.5 dB at Golden Springs Drive) - Brea Canyon Road (67.5 dB north of the 60 Freeway) Union Pacific Railroad in the City of Industry, which runs adjacent to the City in two locations, north of the Pomona (60) Freeway and west of the Orange (57) Freeway (these areas are buffered by "light' manufacturing and the Liftle League Park (playfields). Additional data on the parameters of this noise study are provided in the Noise Appendix. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .June 8, 1992 II -G-10 FIGURE II -G- 4 400' 350' 300' 250' 200' 150' 100' 50' 0' 50' 100' 150' 200' 250' 300' 350' 400' 1111111111111111111111111111111111I GREATER THAN 70 CNEL IM70-65 CNEL 65-60 CNEL FEDLESS THAN 60 CNEL SOURCE: Endo Engineering, 1990. I LAN N I NG N ETV1 ORK RAILROAD NOISE n � 0 3 S N N y D H U N iW e Z g = R U o V g w Z L== �w >y 0 LU O E W 'moi O Z (D J d LU 6 O 2 l 9t CL � O m71 * Table II -G-3 Existing Noise Conditions 1 CNEL Distance to CNEL Contour StreetRocation ADT Right -of -Way at CL 75 70 65 60 State Route 57 North of State Route 60 126,000 150 75.9 170 355 759 1,632 State Route 57/State Route 60 North of Grand Avenue 226,000 150 79.7 296 632 1,358 2,924 South of Grand Avenue 233,000 150 79.8 301 641 1,379 2,970 State Route 60 East of State Route 57 147,000 150 77.8 224 473 1,015 2,185 West of Stale Route 57 168,000 150 77.8 224 473 1,015 2,185 Dlamond Ear Boulevard East of Brea Canyon Rood 17,400 100 63.6 30 44 82 170 South of Fountain Springs Road 20,700 100 64.3 31 47 90 189 South of Pathfinder Road 27,000 100 65.5 34 55 107 227 North of Pathfinder Road 28,200 100 65.7 36 57 110 232 South of Grand Avenue 31,000 100 66.1 37 60 117 246 North of Grand Avenue 24,400 100 65.0 33 51 100 210 North of Steep Canyon Road 25,000 100 65.1 33 52 101 213 South of Golden Springs Drive 29,300 100 64.4 31 48 92 192 North of Golden Springs Drive 32,800 100 66.3 36 60 121 256 South of Sunset Crossing Road 31,300 100 66.1 35 59 117 248 North of Highland Valley Road 18,600 100 66.2 35 60 119 252 South of Temple Avenue 16,700 100 65.7 34 56 111 234 Colima Road West of Calboume Drive 17,700 100 64.9 32 50 99 207 West of Lemon Avenue 19,800 100 66.4 35 61 123 260 East of Lemon Avenue 19,900 100 66.5 36 62 125 264 West of 60 Freeway 22,100 100 64.5 31 48 93 195 West of Brea Canyon Road 29,200 100 65.7 33 56 111 234 Golden Springs Road East of Brea Canyon Road 19,300 100 62.5 23 36 69 146 West of Copley Drive 18,000 100 62.2 23 35 66 139 West of Grand Avenue 19,700 100 62.6 23 36 70 148 East of Grand Avenue 20,700 100 62.8 24 37 72 152 West of Prospectors Road 16,500 100 63.2 24 39 77 162 West of Diamond Bar Boulevard 16,600 100 61.9 22 34 64 133 East of Diamond Bar Boulevard 16,400 100 61.8 22 33 63 131 East of Sunset Crossing Road 10,400 100 61.2 22 31 58 120 South of Temple Avenue .. 10,600 100 61.3 22 32 59 121 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-13 Table II -G-3 Existing Noise Conditions 1 I FHWA Analysis based on existing Average Daily Traffic (ADT), as prepared by DKS Associates (July 1991). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-G-14 CNEL Distance to CNEL Contour streetA.00 l ADT Right -of -Way at CL 75 70 65 60 Grand Avenue West of Golden Springs Drive 27,400 100 65.5 34 55 107 227 East of Golden Springs Drive 24,700 100 65.1 33 52 101 213 West of Diamond liar Boulevard 23,600 100 64.9 32 51 99 207 East of Diamond Bar Boulevard 19,700 100 64.1 31 46 88 183 East of Longview 16,600 100 63.4 30 43 80 165 Pdhfindar Road West of Peaceful Hills Road 4,300 100 57.5 25 28 39 70 West of 57 Freeway (SB) 14,600 100 62.8 28 40 73 151 East of 57 Freeway (SB) 20,200 100 64.2 30 47 89 187 West of Diamond Bar Boulevard 13,000 100 62.3 28 38 68 140 Brea Canyon Road South of Silver Bullet Drive 8,000 100 61.3 22 32 59 121 North of Diamond Bar Boulevard 4,400 100 58.8 20 25 42 84 South of Pathfinder Road 7,600 100 59.9 26 32 50 99 North of Pathfinder Rood 10,100 100 61.2 27 35 59 119 North of Via Sorella 10,200 100 61.2 27 35 59 119 - South of Colima Rood 15,500 100 63.0 29 41 75 156 North of Colima Road 28,300 100 66.9 37 65 132 281 North of Pomona Freeway 32,700 100 67.5 39 70 144 308 North of lycoming Street 26,500 100 66.6 36 62 126 268 North of Washington Street 20,500 100 66.6 36 62 126 268 Brea Cyn. Cut -Off Road South of Pathfinder Road 10,500 100 59.8 11 22 45 97 sunset Crossing Road West of 57 Freeway 5:800 100 57.3 19 23 35 67 Lemon Avenue North of Colima Road 12,100 100 63.2 30 42 78 160 Wdnuf Drive West of Lemon Avenue 5,200 100 56.8 19 22 33 63 Chow Mils Parkway North of Chino Avenue 30,000 100 65.9 35 57 114 241 Chino Avwmm East of Chino Hills Pkwy. 10,000 100 61.0 13 26 54 117 Source: Endo Engineering (1991) based on Draft Circulation Element by DKS Associates (July 1991). I FHWA Analysis based on existing Average Daily Traffic (ADT), as prepared by DKS Associates (July 1991). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-G-14 (3) Stationary Noise Sources Stationary noise sources include "fixed sources," such as industrial machinery, mechanical equipment, etc. Industrial noise generated by processing and operation is usually of long duration at relatively low frequencies. Construction sources generate high noise levels for extended periods of time. Stationary sources of noise within Diamond Bar consist of the following: • Mechanical electric equipment (air conditioners, refrigeration units and filters, air compressors, Industrial plant machinery); • Power tools (lawn mowers, leaf blowers, and other gardening equipment); • Construction and industrial activities (truck pickup and loading, car wash facilities, Industrial operations); and • Human -related activities (loud music, radio, T.V., loud parties, children playing). Stationary noise sources that significantly affect the environment are typically associated with heavy Industrial land uses such as manufacturing. Since the only industrial activity within the City Is "light" Industrial, located north of the 60 Freeway on either side of Brea Canyon Road, there are no known significant sources of stationary noise. (4) Local Noise Conditions Not all local noise conditions can be easily identified, since the topography and natural features within Diamond Bar can reduce noise by buffering receptors, or increase noise levels by reflecting unwanted sound. It is difficult to determine actual sources of noise at times. Reflection and frequency changes can change incoming sound to the point that the source and direction cannot be determined without special instruments. Likewise, man-made structures buffer and reflect noise, and, in some cases, can amplify noise by reflecting and concentrating sounds. To determine site-specific noise conditions, the City can require development projects located adjacent to local mobile and stationary noise sources to submit noise studies. Such studies would include appropriate measures to effectively attenuate interior noise levels. To assist in monitoring future noise conditions, the City can require noise studies from developments that represent potential stationary (or mobile) sources of noise. These studies would be most appropriate for uses proposed adjacent to public use areas, residential neighborhoods, or sensitive natural areas. Such studies may show that certain locations such as canyons or ridgetops, will not unduly concentrate sound to the detriment of the ultimate user of the property. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-15 (5) Sensitive Receptors Due to the physiological and psychological impacts of noise on humans, the placement of noise sensitive land uses near incompatible noise intrusive land uses should be studied to mitigate noise impacts. Those land uses which are deemed "noise sensitive" include residential dwelling units, schools, day care facilities, libraries, churches and places of worship, health care facilities, hospitals, rest homes, and any other use considered to be noise sensitive by the local jurisdiction. The location of sensitive noise receptors is shown in Figure II -G-6. Based on the noise analysis prepared by Endo Engineering, there are no sensitive receptors that experience exterior noise levels in excess of 65 dB, either from local roadway or stationary sources. Figure II -G-3 provides a comparison of land uses compatible with certain noise levels. The rating system is based on the CNEL method, commonly used to evaluate loudness, duration, and time of noise occurrence. The exterior noise criteria for compatibility on this scale is generally 65 dB CNEL. Figure II -G-3 shows the four ranges of noise levels compared to various types of land uses: clearly compatible, normally compatible, normally incompatible, and clearly incompatible. Table II -G-4 and 7 Figure II -G-7 show normally acceptable interior and exterior noise standards. (6) Noise Attenuation The transmittal of sound involves three statistical components: source, transmission path, and receiver. Noise can be mitigated by treatment of any of the three components such as reducing noise source, increasing the distance (path), or placing a barrier between the noise source and receiver, and Insulating the receiver. For example: Fixed Noise Sources A doubling of distance (transmission path) will produce a 6 dBA reduction in sound level. Transportation Sources A doubling of distance (transmission path) will produce a 4.5 dBA reduction in sound level. Site Design A row of two-story buildings will provide a reduction of about 10 dBA. The reduction or attenuation of noise and noise sources in Diamond Bar is difficult because the major source of noise is caused from transportation sources (the 57 and 60 freeways). Local governments have little direct control, but the City can reduce the impacts onto the community through design and construction of sound barriers such as walls, berms, and buildings. While such devices significantly reduce noise levels, they are expensive for local governments to install. In addition, local topography precludes the effective use of sound walls in many cases. Other potential attenuation measures include the establishment of standards and criteria that regulate and specify acceptable limits of noise for various land uses. Care should be exercised to prevent the placement of noise sensitive uses such as residences, schools, hospitals, etc. near significant noise generating sources. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-16 � � Z b K cr \ LLJ�kJ Q ui §$A$ k3»= 2o�k Qloe ;2 2@\$.©=�3,, u/$§ �e §ate ui 2 \ \ LU LU §��!§2#}{)§ 3 §2$°�§�k22 z =®�ƒ� E�z ® ��>$$2§2m22 > U (§]�22� @ R\o;��o�_@ k m m �- 22§zz� &�2 &%�z 2 z � \ }/}\}k§k2002 } \re .2 2\/$ f U) -_____�_,2=� E 2--- ===a;R - ) ( Table II -G-4 Local Noise Standards Land Use Ma)dmum 6derior CNEL Mcudmum Interior CNEL Rural, Single Family, Multiple Family Residential 65 dBA 45 dBA Schools: Classrooms 65 dBA 45 dBA Playgrounds 70 dBA Libraries 50 dBA Hospitals/Convalescent Facilities: Living Areas _ 50 dBA Sleeping Areas 40 dBA Recreation: Quiet, Passive Areas 65 dBA Noisy, Active Areas 70 dBA _ Commercial and Industrial 70 dBA _ Office Areas 50 dBA Source: State of California, General Plan Guidellnes. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-18 FIGURE II -G-7 LAND USE CATEGORIES ENERGY AVERAGE CNEL CATEGORIES USES INTERIOR EXTERIOR 2 Residential Single Family Duplex, 4,53 65 Multiple Family Mobile Home 654 Commercial- Hotel, Motel, Transient Lodging 45 655 Industrial Institutional Hospital, School classroom 45 65 Church, Library 45 — Open Space Parks 65 INTERPRETATION 1. Indoor environment excluding: Bathrooms, toilets, closets, corridors. 2. Outdoor environment limited to: Private yard of single family Mufti -family private patio or balcony which is served by a means of exit from inside. Mobile home park Hospital patio Park's picnic area School's playground Hotel and motel recreation area 3. Noise level requirement with closed windows. Mechanical ventilating system or other means of natural ventilation shall be provided per Chapter 12, Section 1205 of UBC. 4. Exterior noise level should be such that interior noise level will not exceed 45 CNEL. 5. Except those areas affected by aircraft noise. INTERIOR AND EXTERIOR NOISE STANDARDS SOURCE: California Office of Planning Research (OPR) I LAN NTNG NETWORK DIAMOND HAE! 2. ISSUES AND OPPORTUNITIES At present, there are extensive locations in the City that experience "significant' noise levels (over 60 CNEL). The City should work with Caltrans to encourage the installation of sound barriers for residential areas along the freeways. Even though sound barriers will not eliminate noise impacts as would be the case for flat areas, they can significantly reduce noise impacts for residential lands adjacent to the freeways. Local noise levels will continue to increase as traffic Increases. Therefore, the City should carefully plan land uses along major roadways so that future residents and/or employees are not impacted by excessive noise. Buildings constructed along major roadways should have adequate setbacks or be designed in such a way as to maintain acceptable interior noise levels. Open space areas, medians, landscaped parkways, block walls, and other noise attenuation devices can be used to mitigate or eliminate potential noise impacts on new development projects. Such measures can also be used to retrofit existing development so as to alleviate existing noise problems, if the City determines that such problems exist. a. Future Noise Levels Buildout of the City and surrounding communities will increase local noise levels, primarily from mobile sources, as local traffic volumes increase. Localized noise levels will also increase temporarily during construction activities. A noise analysis of local roadways was performed by Endo Engineering. At buildout, local noise levels along major roadways will generally increase. The assumptions and factors used to arrive and a summary of the data is included in Table II -G-5. While these noise levels are not significantly adverse, they could be potentially adverse if sensitive land uses were allowed to be built where exterior CNEL noise levels exceeded 65 dB. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-20 Table 11-G-5 Future Noise FHWAAnalysisl A f C D E F O H I J K L M 1 Street ADT CNEL 75 70 65 60 Dis CL Spd 1l2W % Tr % Med 2 Alternative 1 3 State Route 60 4 West of Brea Canyon Rood 255,000 78.7 255 542 1,165 2,508 150 55 48 8.7 45.3 5 West of Grand Avenue 361,000 81.7 400 858 1,845 3,975 150 55 48 12.9 34.0 6 East of Diamond liar Blvd. 201,000 79.2 275 585 1,258 2,708 150 55 48 12.9 34.0 7 Wed of Phillips Ranch Road 179,000 78.7 255 542 1,165 2,508 150 55 48 12.9 34.0 8 State Route #7 9 North of Diamond Bar Blvd. 308,000 80.2 319 682 1,466 3,158 150 55 48 10.3 38.7 10 North of Pathfinder Rood 280,000 80.0 310 661 1,422 3,062 150 55 48 12.0 49.8 11 North of Sunset Crossing Road 187,000 77.6 217 459 984 2,119 150 55 48 10.8 60.8 12 Diamond Bar Boulevard 13 East of Brea Canyon Road 48,000 68.0 41 75 155 332 100 45 25 1.5 99.0 14 South of Fountain Springs Road 48,600 68.0 41 75 155 332 100 45 25 1.5 99.0 15 South of Pathfinder Road 52,300 68.3 43 79 163 347 100 45 25 1.5 99.0 16 North of Pathfinder Road 54,200 68.6 46 82 169 361 100 45 28 1.5 99.0 17 South of Grand Avenue 60,000 69.0 47 87 180 383 100 45 28 1.5 99.0 18 North of Grana! Avenue 36,500 66.8 37 64 130 276 100 45 25 1.5 99.0 19 North of Steep Canyon Road 38,000 67.0 38 66 134 285 100 45 25 1.5 99.0 20 South of Golden Springs Drive 44,000 66.2 35 60 119 252 100 40 25 1.5 99.0 21 North of Golden Springs Drive 49,900 68.1 42 77 158 337 100 40 25 3.0 71.3 22 South of Sunset Crossing Road 47,000 67.8 41 73 151 322 100 40 25 3.0 71.3 23 North of Highland Valley Road 28,300 68.0 41 75 155 332 100 50 25 3.0 71.3 24 South of Temple Avenue 25,800 67.6 40 71 146 312 100 50 25 3.0 71.3 25 Colima Road 26 West of Calboume Drive 26,900 66.7 36 63 128 273 100 50 24 1.5 99.0 27 West of Lemon Avenue 30,000 68.2 42 77 160 343 100 50 24 3.0 71.3 28 East of Lemon Avenue 30,300 68.3 42 79 163 348 100 50 24 3.0 71.3 29 West of Pomona Freeway 33,600 66.3 35 60 121 256 100 40 24 3.0 71.3 30 West of Brea Canyon Road 44,400 67.6 39 71 147 313 100 40 24 3.0 71.3 31 Golden Springs Road 32 East of Brea Canyon Road 29,300 64.3 26 45 90 191 100 40 18 1.5 99.0 33 West of Copley Drive 27,400 64.0 26 43 86 183 100 40 18 1.5 99.0 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8,1992 11-G-21 Table II -G-5 Future Noise FHWA Analysis] A 5 C D E F G H I J K L M 34 Sheet ADT CNEL 75 70 65 60 Dis CL Spd 1l2W % Tr % Med 35 West of Grand Avenue 29,300 64.3 26 45 90 191 100 40 18 1.5 99.0 36 East of Grand Avenue 31,400 64.6 27 47 94 200 100 40 18 1.5 99.0 37 West of Prospectors Road 25.100 65.1 28 50 101 216 100 45 18 1.5 99.0 38 West of Diamond Bar Blvd. 25,200 63.7 25 42 83 175 100 40 18 1.5 99.0 39 East of Diamond Bar Blvd. 24,900 63.6 25 41 81 172 100 40 18 1.5 99.0 40 South of Temple Avenue 16.100 63.1 24 39 76 159 100 45 18 1.5 99.0 41 Grand Avenue 42 West of Golden Springs Drive 49,100 68.1 42 77 158 337 100 45 25 1.5 99.0 43 East of Golden Springs Drive 42,000 67.4 39 70 142 303 100 45 25 1.5 99.0 44 West of Diamond Bar Blvd. 55,000 68.6 44 82 170 363 100 45 25 1.5 99.0 45 Pathfinder Road 46 West of Peaceful HUB Road 6,600 59.3 26 30 47 90 100 45 24 1.5 99.0 47 West of Orange Freeway (SB) 22,200 64.6 31 49 94 198 100 45 24 1.5 99.0 48 East of Orange Freeway (SB) 30,700 66.0 34 58 116 245 100 45 24 1.5 99.0 49 West of Diamond Bar Blvd. 19,800 64.1 30 46 88 184 100 45 24 1.5 99.0 50 Brea Canyon Rood 51 South of Silver Bullet Drive 12,200 63.2 24 39 77 162 100 50 18 1.5 99.0 52 North of Diamond Bar Blvd. 6,700 60.6 21 29 53 109 100 50 18 1.5 99.0 53 South of Pathfinder Road 11,600 61.8 27 37 64 130 100 45 24 1.5 99.0 54 South of Pathfinder Road 15,400 63.0 29 41 75 156 100 45 24 1.5 99.0 55 South of Colima Rood 23,600 64.9 32 50 99 207 100 45 24 1.5 99.0 56 North of Colima Road 42,200 68.6 44 82 170 364 100 45 24 3.0 71.3 57 North of Pomona Freeway 48,700 69.2 47 89 187 399 100 45 24 3.0 71.3 58 North of Washington Street 30,600 68.3 42 79 163 348 100 50 24 3.0 71.3 59 Brea Canyon Cut-off Road 60 South of Pathfinder Road 16,000 61.6 14 28 60 128 100 40 6 1.5 99.0 61 lemon Avenue 62 North of Colima Road 18,400 65.0 33 51 100 210 100 45 25 3.0 71.3 63 Walnut Drive 64 West of Lemon Avenue 7,900 58.6 20 25 41 81 100 35 18 3.0 71.3 65 Chino Hills Parkway 66 North of Chino Avenue 35,000 66.6 37 63 126 268 100 45 25 1.5 99.0 67 Chino Avenue 68 East of Chino Hills Parkway 17,200 63.3 18 36 77 166 100 45 6 1.5 99.0 1 Projected to 2010, based on projected traffic from DKS study. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -G-22 RD -77-108 Noise Assumptions 1. Temporal Traffic Distribution Assumed (percent): Typeof Vehicle Day Evening Night Automobile 74.41 12.38 9.21 Medium Truck 1.56 0.09 0.19 Heavy Truck 0.64 0.02 0.08 Source: Orange County EMA representing 31 arterial Intersections throughout the County and assumed to be typical of southern California arterials. ll. Road Grade Assumptions — level terrain and roadway. Ill. RD -77-108 Input Parameters — See previous table. N. RD -77-108 Input Parameters Definitions: ADT means average daily two-way traffic volume provided by DKS Associates. CNEL is provided at 150 feet from the freeway centerlines and 100 feet from all other roadway centerlines. Dis CL means distance to centerline for CNEL calculation. Spd means the posted speed limits were taken from "Draft Circulation Element for the City of Diamond Bar" prepared by DKS Associates, June 1991. 112W is the effective half -width of the roadway (the distance from centerline to the center of outermost travel Ione); taken from "Draft Circulation Element for the City of Diamond Bar" prepared by DKS Associates, June 1991. % Tr is the percentage of trucks on the roadway. Truck mix along the freeways was taken from 01989 Annual Average Daily Truck Traffic on the California State Highway System." The rest of the roadway link truck mix was provided by ? % Med is the percentage of medium trucks. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .lune 8. 1992 II -G-23 H. CULTURAL RESOURCES EXISTING SETTING The cultural resources of the Diamond Bar area include of fossils of prehistoric plants and animals, artifacts of local inhabitants before recorded history, and relics of activities in the recent past. a. Paleontological Resources Much of the Diamond Bar area is underlain by the Puente Formation, a strata of rock that bears tiny fossils: During the Miocene period (11-25 million years ago), this region was covered by a vast inland sea some three miles deep (see also Section it -B, Earth Resources and Seismicity). Silt and sediments containing plants and animals were laid down thousands of feet thick during this time. Eventually, this area was uplifted by tectonic (geologic) activity as the inland sea retreated. Today these sediments yield tiny fish scales, plant leaves, shells, and other Miocene fossils. Fossil materials can be found throughout the Puente Formation, which underlies the entire City and sphere of influence. Micro -fossils (leaves, scales) are most abundant in the Soquel member (McLeod 1990), and the Chino Hills Specific Plan EIR noted that significant vertebrate fossil remains have been found in chalky deposits of the Yorbo member (EDAW 1982). Both of these members underlie a large portion of the City. Figure I1 -B-2 shows the local distribution of the Soquel and Yorba members. A detailed records search was conducted by the Los Angeles County Museum of Natural History for both vertebrate (animals with backbones such as fish and mammals) as well as invertebrates (animals without backbones such as insects and mollusks or shellfish). According to Dr. Samuel McLeod, the Puente formation "is very productive locally, in terms of fish (fossils)". The most common materials found are small leaves, fish scales, even partial or whole skeletons at times, in either silty or diatomaceous earth (soil containing diatoms or microscopic sea plants). Dr. Luella Saul and Dr. Phillip Owen with the Los Angeles Museum also indicated that two sites (LRCM 7693 and LACM 1209) in the Puente Hills just west of Diamond Bar contain 'siliceous shales that has yielded Miocene barnacle plates, mud pectins, foraminifera (another type of plankton) as well as important vertipectin fossils (Chione temblorensis)". Dr. Mcleod indicated that the entire Puente formation should be considered to have the potential to yield significant fossils. According to the records search, there are no recorded paleontological sites within the Diamond Bar City limits or the sphere of influence. However, there are two recorded sites just outside of the City; there location are shown in Figure II -H-1. These sites have been labeled by the Los Angeles County Museum (LACM) according to the numerical order in which they were discovered: LRCM 4349 This site has since been developed, but was located in the Phillips Ranch northeast of the City, near Village Loop Road and Old Pomona Road. It contained plant materials typically found throughout the Puente formation, primarily fish scales, leaves, and some shells. This site originally yielded a greater proportion of fossiliferous materials than other unrecorded sites in the Puente formation, but was not unique in terms of scientific collection (McLeod 1990). LRCM 7153 Spadra Landfill. This former local "dump" appeared to be an old quarry site. It yielded a large variety of intact Miocene fish fossils including pipefish and a fully articulated whale skeleton. It is located north of Valley Boulevard just west of the San Jose Creek in Pomona, and is still used for amateur and educational collecting. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-H-1 b. Archaeological Resources The Diamond Bar area was once inhabited by small bands of Gobrielino Indians. These local hunter -gatherers foraged on the basin floor and into the surrounding hills, utilizing the intermittent streams with their abundant wildlife and edible plants. It would be these some attributes that would eventually attract the early Californians to this area. The Gabrielinos were probably the most prominent local tribe in this area from 500 to 1500 AD. They ranged from the foothills of the San Gabriel Mountains (from which their name was derived) to the Pacific coast, and even to the offshore islands. The Gabrielinos were among the most wealthy, populous, and powerful ethnic aboriginal nationalities in early California. Their main settlements were villages occupied continuously during extended foraging activities; less important settlements were used only seasonally or irregularly. Major settlements were usually located near year-round springs or streams for sources of water, food, and plants. Minor settlements were located along intermittent streams or high points for observation. The Spanish explorers first made contact with the Gabrielinos around 1500 AD. The largest increases in Spanish settlement occurred during the 1700's. At that time, the Gabrielino population was estimated at 5,000 people. European contact greatly reduced the local Indian population due to disease, starvation, and forced assimilation of the European culture. By 1900, the Gabrielinos had ceased to exist as on identifiable cultural entity (LACDRP 1983) (CPP 1987). A records search for recorded archaeological resources was conducted by the Archaeological Information Center with the University of California at Los Angeles (UCLA). There are, at present, five (5) recorded archaeological sites within the City or sphere of influence (UCLA 1990). Figure II -H-1 shows the general location of these sites, although specific locations are kept confidential to protect them from vandalism or illegal collection. The archaeological sites identified in Diamond Bar are: • CA -LAN 852, 853, 854 This location actually represents three separate sites, and has yielded lithic scatter including two chert cores and one chert flake. Although this general area has already been developed, it should be examined further to determine if any significant artifacts remain. If any are found, they should be collected by qualified personnel and housed in an appropriate facility. All three sites were last surveyed in 1976. CA -LAN 1414 This site is along the boundary of the City of Industry near the junction of the 57 and 60 freeways. It has yielded granite fragments of pestle, bifacial manos, flakes, tarring pebbles, and bowls; charcoal was also found. It was last surveyed in 1988. • CA -LAN 1704 This site overlooks Tanner Canyon in the Tres Hermanos area. It contained a chopper, mano and metate fragments, and possibly a hommerstone. It is considered to have been a temporary milling station. Use and condition of site indicates that additional lithic materials may be present. In total, 21 different archaeological studies have been performed by qualified personnel within the City or its sphere of influence. Figure II -H-1 also shows the areas within the City that have been previously surveyed. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -H-2 \ ?5u )/ $(2\§! 7 /\ � 0 m > )\!£ c § z 2 _ . LL) O q < * -- ::D 3\ �� » k § «2 — The remainder of the City and the sphere of influence may harbor additional archaeological resources and artifacts, especially near permanent or intermittent sources of water or high observation points. The City and its sphere of influence both contain additional locations that have one or more of these characteristics that have not been surveyed. Such areas may include, but not be limited to: • Sandstone Canyon (stream and oak trees), • Canyon and hillsides northeast of Silver Cloud and Trigger Drives (trees near Brea Creek), • All canyons, slopes, and ridges of Lower Tonner Canyon drainage (perennial water, trees, and visibility), • Upper Sycamore Canyon (intermittent water, trees, and visibility), • Any high points surrounding canyons with intermittent water (such as Sandstone or Upper Sycamore Canyons), • Low hills west of the 57/60 freeway interchange around Grand Avenue, which are actually in City of Industry but adjacent to Diamond Bar (near San Jose and Diamond Bar Creeks, visibility, and previous site in area). C. Local History Very little remains of the quiet but dynamic history of Diamond Bar. During the Spanish colonial period, Juan M. Alvarado, the Spanish governor of California, granted large tracts of land in Southern California to settlers during the 1830's. Ranching became the most productive occupation due to the relatively dry climate and steep terrain. Under an 1840 Spanish land grant, Jose de la Luz Linares was awarded a troct of land that became known as Rancho Nogales, which means "Ranch of the Walnut Trees". Although there are no records of exact boundaries, it is believed that this rancho encompassed much of the City and its sphere of influence. After the death of Jose Linares in 1847, his widow sold the prime section of the rancho to Ricardo Vejar. By 1856, Vejar had obtained 22,000 acres, or virtually all, of the original Los Nogales Ranch. At that time, the Vejar holdings occupied the land from what is today the City of Pomona, west to the present City of Walnut, and south to Brea Canyon. By 1858, Vejar was known as the wealthiest man in Los Angeles County, and as one of the most powerful cattle ranchers in the country (CPP 1987). Vejar erected a large adobe house at the foot of the Puente Hills which became a cultural center and meeting place for other local ranchers. The adobe was built in 1853 but was demolished in 1955. Today, a scale model of the adobe is located near its original site on the grounds of the Lanterman State Hospital (CPP 1987). When a Butterfield State Line Overland Mail Route opened near the Ranch, a local businessman opened a tavern, near where the 57 Freeway intersects Pomona Boulevard. It was called Spadra when Wells Fargo took over the Butterfield Line, and it retained the name when Wells Fargo was taken over by the Southern Pacific Railroad in 1872. A long period of drought in the late 1860s drove many local ranchers into bankruptcy, and forced the sale of a majority of Vejar's Ranch. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-H-4 Rancho Los Nogales was periodically divided and recombined prior to modern times. During the late 1860's, the ranch was broken up into smaller holdings. But, in 1873, many of the original parcels were consolidated back into one ranch by two local cattlemen. The ranch thrived, at one time supporting over 5,000 head of sheep, several hundred cattle, and 100 head of horses. However, the ranch was again divided in 1890. In 1918, various parcels of the original rancho were again combined. These parcels were combined by Frederick Lewis into a new ranch called Diamond Bar. Lewis tried to raise hogs for a while, but this eventually failed and he returned to cattle ranching. The Bartholome Corporation purchased the Diamond Bar Ranch in 1943. The Bartholome family moved onto the ranch and continued raising cattle. Water facilities such as wells and pipes were built, although there is no record of their location or arrangement. The Bartholome family was considered the first local ranchers to permanently irrigate pasture land (CPP 1990). In 1956, the Christiana Oil Corporation and the Capital Company, a subsidiary of the Transamerica Corporation, purchased the Diamond Bar Ranch. A master plan and zoning map were approved by the County Board of Supervisors in 1958. When residents moved into the first new houses in 1960, Diamond Bar moved out of the ranching era and into the suburban development phase of its history (Westways 1962). Diamond Bar was originally master planned to be a self-sufficient community, with a wide variety of social amenities for its residents and workers. It was once planned to have some 30,000 homes and a population of 100,000 people. However, the building boom of the 1960's did not succeed in providing all of the improvements originally envisioned. During this time, the Diamond Bar Development Corporation requested and received a series of zone changes lowering densities for various projects in Diamond Bar. In 1976, the County formed a Municipal Advisory Committee (MAC) for Diamond Bar to advise the County on local zoning issues. Until 1985, the MAC contained four elected members appointed by the areas's County Supervisor. After that, all members of the MAC were elected. In June of 1988, local County residents voted to form a new city. On April 8th, 1989, the City of Diamond Bar officially incorporated, becoming the 86th city within the County of Los Angeles. d. Historical Resources A review of historic maps indicates there was no identified development within the City or the Puente Hills prior to 1900. Although Brea Canyon Road does appear as early as 1894, there is no development, structures, or improvements associated with it. The road served to connect the East San Gabriel Valley with Brea and Orange County as early as the 1890's. The only development that appears on 1942 maps are some dirt roads and a few structures and buildings associated with the Diamond Bar Ranch. A records search for recorded historical resources was conducted through the Archaeological Information Center with the University of California at Los Angeles (UCLA). According to this survey, there are at present no recorded historical sites within a one -mile radius around the City or its sphere of influence (UCLA 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -H-5 2. ISSUES AND OPPORTUNITIES Since fossils, Indian artifacts, or historical relics could be found almost anywhere in the City, parcels that have not been previously surveyed for paleontological, archaeological, or historical resources should have adequate testing and study prior to development. The City should consider an ordinance to help protect cultural resources (such as fossils or Indian artifacts) discovered during grading or construction. Such an ordinance should require immediate notification of appropriate personnel upon discovery of any artifacts, and prevent destruction of any artifacts until they can be adequately surveyed and salvaged, if necessary. Although few cultural sites or resources have been identified, the City may wish to form a Cultural Commission or some other City -sponsored group to study and make recommendations to the City on cultural resources. The City may wish to consider providing, sponsoring, or soliciting building space in the City for a cultural heritage museum. Such a facility could possibly be incorporated into some commercial or recreational venture to attract tourists. Residents in the City may wish to form a Cultural Heritage or Historical Society, perhaps in cooperation with the Pomona Historical Society. Such a group could help preserve artifacts from Diamond Bar's past, such as fossils, indion tools, or historical relics, including pictures and stories. The City may wish to seek out or advertise for elderly residents who could provide an oral history of the area. This could be done in conjunction with local educational institutions, most likely either high schools or colleges. The City may wish to plan for the proper curation of artifacts found within the City, either within the City itself, through some local civic group, or through an appropriate educational institution. The local school districts may wont to participate with the City, either in arrangements for facilities or educational programs to support local curation. The City may wish to evaluate structures or improvements suspected of being older than 45 years (if any) according to the criteria for inclusion in the National Register of Historic Places. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -H-8 1. SOCIOECONOMICS EXISTING SETTING The quality of life in Diamond Bar is directly affected by the affluence of its residents and the overall health of the local economy. The demographic characteristics that most affect the social and economic environment of Diamond Bar are population, housing, and employment. As part of this analysis of socioeconomic factors in the City, Urban Decision Systems, Inc. collected 1980 federal census and other recent statistical data for the Diamond Bar area. The City occupies four complete census tracts.(4033.12 through 4033.15) as well as portions of tract 4033.02 (shared with unincorporated Rowland Heights) and portions of tract 4033.11 (shared with Pomona). The City also occupies two zip codes. Zip zone 91765 covers all of the City east of the 57 Freeway, while zip zone 91789 covers Walnut and the parts of Diamond Bar west of the 57 Freeway. This division makes statistical analysis inaccurate since Diamond Bar cannot be separated from the total figures. Statistical Limitations The City of Diamond Bar officially incorporated on April 18th, 1989. Prior to that, it was an unincorporated community in the County of Los Angeles. However, the new City boundaries were larger than the boundaries of the older community. Demographic information collected before incorporation may not reflect present boundaries, and so statistical data from different sources may not necessarily agree. a. Population The City of Diamond Bar presently has 59,221 residents compared to a 1980 population of 31,501 residents. This represents a total increase of 88 percent, or an average annual increase of 8.8 percent, during the past decade. By 1995, the City's population is expected to increase to 64,000 (Planning Network 1991). This represents a considerable slowing of growth, from 7.0 percent to 3.8 percent annually as the readily available vacant land is built out. Table II -1-1 presents historical and projected population change for Diamond Bar based on the 1980 census and preliminary data from the 1990 census. Conflicting Data The following are examples of the inconsistent statistical data for the Diamond Bar area. According to information available in the Diamond Bar Library, the City's 1988 population was 60,333 residents, which is higher than the estimate reported by Urban Decision Systems for 1990 (59,22 1). However, the Los Angeles County Department of Regional Planning, Population Research Section Bulletin (dated 1/1/87) reported a 1987 population of only 39,161 residents. Athird source, the Local Agency Formation Commission (LAFCO) staff report for the proposed incorporation of Diamond Bar, reports the 1988 City population to be 60,333 residents. This figure was based on three (3) times the number of registered voters at the time (20,111). These differences may be due to boundary changes since incorporation. The County's 1980 census population figure of 74,000 for Diamond Bar most likely includes substantial lands outside of the present City boundaries. Finally, preliminary figures from the 1990 federal census indicate a 1990 City population of 53,672 residents. According to the Los Angeles County Department of Regional Planning, the 1980 census reported Diamond Bar's population at 28,053 residents, although Urban Decision Systems estimated it at 31,501 residents. This discrepancy is probably due to boundary differences between what was counted as Diamond- Bar for the census versus the current City boundaries. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8 1992 11-1-1 For the purposes of the 1991 General Plan, the preliminary 1990 census figure will be used as the most current and applicable to the existing City boundaries. The City's present population of 53,672 represents 0.6 percent of the estimated 8.86 million IA County population estimated in the preliminary 1990 census figures. Age Distribution The City's population is slowly growing older. A comparison of age groups shows that the over 25 age brackets (25-34, 35-44, and 45-54) are increasing while the under 25 groups are slightly declining. This figures also reflect increasing student enrollments at local schools, which would tend to increase numbers in the 0-5, 6-13, and 14-17 age brackets. Table II -1-1 also provides an age group distribution for the City's population. Median Age Table 11-1-1 29.8 Total Population 31,501 53,672 Population Age Breakdown INCREASE Age Group (Years) 1989 1990 1995 0- 5 10.9 11.9 11.1 6- 13 16.4 16.1 16.8 14- 17 8.0 6.4 6.5 18-20 4.6 3.4 3.4 21 -24 5.3 4.3 3.9 25-34 22.3 20.0 17.2 35-44 17.1 21.6 22.8 45-54 9.1 9.7 11.5 55-64 4.4 3.8 3.7 65 + 2.0 2.8 3.1 Median Age 27.5 29.0 29.8 Total Population 31,501 53,672 64,000 INCREASE Persons 22,171 10,328 Total Percent 70 19 Annual Average 7.0 3.8 Source: 1980 census data from Los Angeles County General Plan, 1988 Report. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-2 Ethnicity Diamond Bar has become an ethnically diverse community. In 1980, minorities represented 13.3 percent of the City's population, up from a 1970 figure of 10.9 percent (Library CU #14). By comparison, minorities comprised 47 percent of Los Angeles County's population and 43 percent of the State's population. According to preliminary census figures, Diamond Bar's ethnic population has increased to 47 percent in 1990. Asians have shown the most increase, with other groups showing slight increases over the some period. Table II -1-2 presents data on the regional distribution of minorities, while Table II -1-3 provides ethnic data for Diamond Bar. Table II -1-2 Regional Ethnicity (1990)1 ETHNIC GROUP CITY COUNTY STATE Caucasian 53.0 40.8 57.2 Latino 2 15.1 37.8 25.8 Black 5.0 10.5 7.0 Asian 24.0 10.2 9.1 Other 1.0 0.7 0.9 Source: Prelimierny 1990 census data from Los Angeles Times, May 6, 1991. Table II -1-3 Diamond Bar Ethnictty3 ETHNIC GROUP 1980 1990 1995 Caucasian 86.7 53.0 49.0 Hispanic/Latino 15.1 17.0 18.0 Black 5.1 5.0 5.0 Asian 6.5 24.0 27.0 Other 1.7 1.0 1.0 Source: Preliminary 1990 census figures. 1995 figures are projections by Planning Network and Urban Decision Systems, Inc. based on 1980 and preliminary 1990 census data, and from other recent demographic data. 1 Total percentage of population. 2 The Latino (all groups) replaced the Spanish Origin category of the 1980 census. The old term meant that a person could be counted as Caucasian or other ethnic group and may also be of Spanish origin. 3 1995 figures based on estimates by Planning Network and Urban Decision Systems, Inc. based on preliminary 1990 and 1980 census data. Hispanic category in 1980 census changed to Latino (all groups) for 1990 census to prevent overlapping of data. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT in,-- R 199? II -1-3 Household Composition The composition of households has remained fairly stable over the past decade. Almost half of the households have 3-4 persons, with a quarter having 2 persons. This contributes to a present average of 3.49 persons per household. This represents only a slight increase (+4 percent) from 3.35 persons in 1980. During the last decade, the total number of families in the City increased from 8,315 in 1980 to 14,404, while the total number of households increased from 9,400 to 16,987 in 1990. These figures represent increases of 73 percent and 81 percent, respectively. By comparison, the total population increased by 88 percent during the same period. These figures indicate that slightly fewer households and families are being housed locally compared to overall population increases. Table II -1-4 provides details on historical and projected household composition in Diamond Bar. Education According to 1980 census figures, approximately 17.5 percent of City residents have not graduated from high school, while 41 percent have graduated. A quarter (25%) of City residents have taken some college courses, while 16.5 percent are college graduates. In 1980, the median amount of education residents had was 12.8 years. It is likely that these figures have significantly increased during the past decade, as evidenced by the tremendous rise in individual and household incomes during that time (1980 Education Characteristics - East County Region, LACDRP Statistical Research Branch). Income Since 1980, household and family incomes in Diamond Bar have almost doubled (+90%), and they area projected to increase another 25 percent by 1995. Incomes will have increased from a combined value of $33,000 in 1980 to $80,000 by 1995 (UDS 1990). Table II -1-5 provides average and median income values for households as well as families in Diamond Bar. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT I-- a 10013 11-1-4 Table 11-1-4 Household Composition Household Size 1980 1990 1995 1 Person 7.5 12.7 14.9 2 Persons 25.0 27.4 28.3 3-4 Persons 48.2 45.9 45.0 5 + Persons 19.2 14.1 11.8 Average Household 3.35 3.49 3.54 Size 34,410 66,297 83,000 Toial Households 9,400 16,987 20,606 Toial Families 8,315 14,404 17,106 Source: 1980 and preliminary 1990 census data; projections by Planning Network and research by Urban Decision Systems, Inc. 1990. Table 11+5 Income ($) Income 1980 1990 1995 HOUSEHOLDS Median 31,153 58,051 70,098 Average 33,288 63,546 79,346 FAMILIES Median 32,039 62,131 76,418 Average 34,410 66,297 83,000 Source: 1980 census data and projections by Urban Decision Systems. Inc. 1990. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT II -I-5 June S. 1992 b. Housing The amount of housing in the City has increased in proportion to the population growth. From 1980 to 1990, housing increased from 10,153 to 17,664 units. This represents a ten-year increase of 80 percent. Urban Decision Systems estimates that housing will continue to increase through 1995, though not as fast as the previous decade. By 1995, the City will have over 21,000 units, which is an increase of 3700 units or 21 percent over five years. The City will continue to be predominately owner -occupied (85%), with vacancy rates of 2-3 percent (LAFCO application data 1988). Since building first began in 1960, Diamond Bar's housing has been largely single family detached units (almost 80 percent), although a significant number of attached and multiple family units have been constructed as well. In 1988, the County of Los Angeles estimated there to be 12,624 total dwelling units in the City, including 3,000 condominiums and townhomes, 300 apartments, and 300 mobile homes (LAFCO 1988). However, a recent survey by Planning Network found 4,132 condominiums and townhomes, 649 apartments, and 294 mobile homes. This survey also found almost 12,000 single family homes. Owners outnumber renters in the City by almost a 7:1 ratio, with only 12.8 percent of occupied units. Historical vacancy rates have been as high as 7-10 percent, although the higher values are probably during times when there was an oversupply of new housing. The 1980 census reported the vacancy rate for the Diamond Bar area to be 6.01 percent (LACDRP 1988). At present, the County estimates that vacancy rates are averaging 2-3 percent (LAFCO 1988). A vacancy rate of 3 percent was used to calculate total units for 1990 and 1995, as shown in Table II -1-6. The housing stock in Diamond Bar is fairly young, with all but 60 units built after 1960 (Library CU #11), compared to only 42 percent of County -wide housing (Los Angeles County Housing Element, 1989). According to the California Market Data Cooperative (CMDC), the most recent annual average resale price of a home in Diamond Bar is $312,324 (April 1990 to March 1991). This is 2.7 percent higher than the average sales price of $304,000 for the previous year (1989-90). Already in 1991, average resole value has increased to $313,468. Annual figures are taken from over 500 resale listings per year. According to CMDC figures, the average home resold in Diamond Bar has 4 bedrooms, has approximately 2,000 square feet of living area, and is 15 years old (build in 1976). In addition to standard suburban development, the City has a large private community. "The Country" is a gate -guarded community located along the eastern border of the City. It occupies 1,250 acres and has been developed into 725 lots with 625 homes (86 percent) already developed. A natural canyon called "The Country Park" occupies 132.7 acres in the center of the development (Davenport 1990). The estimated population of "The Country" is approximately 2200 residents. It should be noted that resale price data also shows that median prices are only about $240,000, which is the "middle" value in terms of numbers of units, as opposed to the arithmetic average. This means that there are many more lower priced homes (probably around $250,000) selling compared to fewer but much "higher" priced homes (over $400,000). An analysis of the price per square foot for resale housing is useful to determine the overall price "scale" of a particular residential community. Based on the latest CMDC figures, Diamond Bar's housing has an average price per square foot of $140-150. Although the general image of Diamond Bar is an upscale community with expensive housing, these values are fairly typical for upper middle class suburban communities in Southern California. These values can be contrasted with established upscale communities such as Rolling Hills Estates ($275/SF) and San Marino ($290/SF). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT II -I-6 June S. 1992 Table II -1-6 Housing Stock Housing 1980 1990 1995 OWNER -OCCUPIED 10,153 17,664 21,223 Units 8,441 14,809 17,603 Percent 83.1 87.2 85.4 RENTER -OCCUPIED 754 678 618 Units 958 2,177 3,002 Percent 34,410 66,297 83,000 TOTAL Units 10,153 17,664 21,223 Occupied 9,399 16,986 20,605 Percent 92.6 96.0 97.0 Vacant' 754 678 618 Percent 7.4 4.0 3.0 Source: 1950 census data and projections by Urban Design Systems, Inc. 1990. 1 Vacancy rates for 1990 and 1995 assumed to be three percent based on UDS and Planning Network estimates. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT II -I-7 June 8, 1992 C. Employment Employment in Diamond Bar is dominated by retail sales, local services, and office uses. Together, these business sectors employ 83.3 percent of the local labor market, as shown in Table II -1-7. Retail trade employs approximately 3,042 workers, or 32.8 percent of the 9,275 workers estimated to be in Diamond Bar (Planning Network and UDS 1990). Most of the existing commercial uses are located along Diamond Bar Boulevard and Golden Springs Road, near the freeway on- and off -ramps or at major intersections (Diamond Bar Boulevard at Grand Avenue and Golden Springs Drive, etc.) The small commercial areas on Colima Road west of the freeway probably add about 15 acres. This area also supports 35 acres of industrial and business park uses. The City also has 138.5 acres of office uses, with the majority concentrated in the Gateway Corporate Center off of Golden Springs Drive, just east of the 57 Freeway. Together, all office uses provide an estimated 4,680 professional jobs in the City (Planning Network), with the majority of them being in finance, insurance, and real estate (UDS 1990). All of these various businesses occupy 5.4 million square feet of buildings. Although land use figures show commercial uses represent only a third of non-residential buildings in the City, many uses in the office and business park categories are classified as retail, which significantly increases the amount of retail -related employees. Table II -1-8 provides a detailed breakdown of building square footage and employees expected according to the various business categories. d. Taxable Sales The non-residential land uses within Diamond Bar generate various revenues towards financing City programs. It is important for any city, but especially new cities, to examine local sources of sales taxes to determine if revenues are 'leaking" into surrounding communities that could be drawn in to fund local services. Table II -1-9 presents 1989 taxable sales data per capita for three different types of cities in Southern California. In terms of comparison cities, all three have similar populations, but have varying income levels and somewhat different mixes of land uses: Arcadia is on upscale, mainly residential community located in the San Gabriel foothills that has recently added some regional commercial uses along the freeway in the past few years. This city has a slightly higher per capita income than Diamond Bar ($21,319 versus $20,828, respectively). Cerritos is a small middle class community but with a large amount of general merchandise and auto sales uses. It has a population is terms of size to Diamond Bar but with a lower per capita income ($15,281 versus $20,828, respectively). Covina has some freeway uses, but in general has a mix of land uses similar to Diamond Bar. Its population is similar to Diamond Bar but with a lower per capita income ($15,421 versus $20,828, respectively). Unfortunately, annual sales data for 1989 was not available for Diamond Bar since it incorporated part way through the year. Tables II -1-10 through 12 compare per capita taxable sales for Diamond Bar versus other cities for the first 3 quarters of 1990. In addition, Tables 11-1-13 through II -1-16 present similar taxable sales data, but by establishment. Even accounting for differences in income, both per capita and per establishment taxable sales data show that City residents are spending much fewer of their "disposable income" dollars in Diamond Bar. Almost all types of businesses show relatively weak sales in both per capita and per establishment categories compared to the three other cities. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-8 Table II -1-7 Employment by Major Industry (1990 estimate) Business Type Employees Percent N Agriculture/Forestry/Fishery 28 0.3 Mining 0 0 Construction 547 5.9 Manufacturing 74 0.8 Transportation/Utilities 37 0.4 Wholesale Trade 111 1.2 Retail Trade 7.272 78.4 Finance/Insurance/Real Estate 334 2.4 Services 1,153 8.2 Unclassified 336 2.4 TOTAL 2 9,275 100.0 Source: Modified by Planning Network from estimates by Urban Design Systems, Inc. 1990 based on *Census ZIP Business Patterns'. 1 Based on Standard Industrial Code (SIC) classifications. 2 Does not Include areas west of the 57 Freeway along Colima or Brea Canyon Roads (UDS 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1,992 III 9 Table 114-8 Employment by Land Usel Industry/Business Type Employees Percent Area (SF) MANUFACTURING/INDUSTRIAL Heavy Manufacturing 0 0 0 General Manufacturing 483 5.2 288,000 Light Manufacturing 0 0 0 Manufacturing, small module 87 0.9 46,000 High-tech activities/research 0 0 0 Wholesale trade, industrial 919 9.9 773,000 Warehousing 0 0 0 General industrial 64 0.7 58,000 Sub -total 1,153 16.7 1,165,000 COMMERCIAL Retail Trade 2,632 28.4 1,783,000 Restaurants and bars 236 2.5 26,000 Personal, rental, repair services 49 0.5 9,000 Automotive repair services 11 0.1 1,000 Equipment rental 13 0.1 2,000 Wholesale trade, commercial 5 <0.1 1,000 General commercial 96 1.0 79,000 Sub -total 3,042 32.8 1,901,000 OFFICE PROFESSIONAL Finance/insurance/real estate 2,055 22.2 567,000 Professional services 1,098 11.8 615,000 Business services 154 1.7 97,000 General office 1,105 11.9 374,000 Medical services 268 2.8 640,000 Sub -total 4,680 50.5 2,293,000 TOTAL EMPLOYMENT 9,275 100 5,359,000 Source: Percentage of employees estimated by Urban Design Systems, Inc. based on 'Census ZIP Business Patterns' (1990). Number of employees calculated by Planning Network based on percentage of employees by category. Building areas calculated by Planning Network based on acreage of land use times approximate building/lot coverage. 1 Industrial and office areas were found to contain some percentage of commercial uses, which would increase both employment and building square footage figures for commercial relative to Industrial and office uses. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-10 Table 11-1-9 Taxable Sales Per Capita 1 1989 Business Type Arcadia Cerritos Covina Apparel Stores 818.26 1,104.32 126.92 General Merchandise 2,231.19 5,641.55 1,974.75 Drug Stores 298.61 152.85 239.66 Food Stores 700.37 279.62 830.95 Package Liquor 75.67 29.04 87.30 Eating & Drinking 1,216.42 838.28 1,176.22 Home Furn. & Appliances 235.20 872.90 266.32 Bid. Mat'I & Farm Implmts. 430.90 1,065.46 1,194.78 Auto Dealers & Supplies 506.25 5,932.31 2,518.25 Service Stations 523.52 475.43 666.14 Other Retail 1,077.39 2,325.15 1,579.93 Total All Retail 8,113.79 18,716.90 10,661.24 Other Outlets 1,784.74 4,972.09 1,646.84 TOTAL ALL OUTLETS 9,898.53 23,688.99 12,308.08 Per Capita Income 2 19,035.00 13,644.00 13,769.00 Source: California Board of Equalization, 'Taxable Sales in California', 1989-1990 1 All figures in dollars. No information is available for sales in Diamond Bar for 1989. 2 Per capita incomes for Arcadia, Cerritos and Covina are from the State Department of Finance, and are adjusted 6 percent per year for inflation since 1987. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT A S S E S S M E N T June 8, 1992 II -1-1 1 Table II -1-10 Taxable Sales Per Capffa 1990 1 st Quarter Business Type Arcadia Cerritos Covina Diamond Bar Apparel Stores 160.88 243.46 27.24 7.25 General Merchandise 434.35 1,141.00 468.49 Drug Stores 92.36 46.07 65.41 37.95 Food Stores 180.87 79.77 219.41 121.20 Package Liquor 21.66 6.20 21.76 8.96 Eating & Drinking 244.09 209.75 294.86 139.85 Home Furn. & Appliances 56.47 188.60 62.49 16.02 Bid. Mat'I & Farm Implmts. 83.08 252.89 252.30 17.10 Auto Dealers & Supplies 134.56 1,479.04 593.03 103.41 Service Stations 98.72 121.94 158.56 134.97 Other Retail 191.10 752.27 360.47 188.29 Total All Retail 1,698.14 4,521.00 2,524.01 775.00 Other Outlets 689.17 1,400.09 393.34 179.57 TOTAL ALL OUTLETS 2,387.31 5,921.09 2,917.35 945.59 Per Capita Income 1 21,319.00 15,281.00 15,421.00 20,828.00 ' General Merchandise for Diamond Bar is included in Other Retail. Source: California Board of Equalization, 'Taxable Sales in California', 1989-1990. 1 Per capita Incomes for Arcadia, Cerritos and Covina are from the State Department of Finance, and are adjusted 6 percent per year for inflation since 1987. Diamond Bar per capita Income is derived from 1990 average household Income (Urban Decision Systems, Inc.). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-12 Table 11-1-11 Taxable Sales Per Capita 1990 2nd Quarter Business Type Arcadia Cerritos Covina Diamond Bar Apparel Stores 218.47 282.38 33.54 7.84 General Merchandise 523.48 1,374.98 508.92 Drug Stores 71.01 35.18 53.60 28.17 Food Stores 168.59 68.50 209.43 111.08 Package Liquor 20.81 7.02 21.99 8.70 Eating & Drinking 254.86 212.92 306,18 161.00 Home Furn. & Appliances 61.09 213.99 68.97 19.19 Bld. Mat'I & Farm Implmts. 81.11 298.85 299.51 29.57 Auto Dealers & Supplies 135.02 1,717.79 658.90 96.14 Service Stations 144.36 121.98 162.59 136.48 Other Retail 220.50 803.93 410.51 170.93 Total All Retail 1,899.30 5,137.53 2,735.18 769.10 Other Outlets 421.10 1,361.10 442.38 182.74 TOTAL ALL OUTLETS 2,320.40 6,498.63 3,177.56 951.84 Per Capita Income 1 21,319.00 15,281.00 15,421.00 20,828.00 *General Merchandise sales for Diamond Bar are included in Other Retail Source: California Board of Equalization, 'Taxable Sales in California', 1989-1990. 1 Per capita Incomes for Arcadia, Cerritos and Covina are from the State Department of Finance, and are adjusted 6 percent per year for inflation from 1987. Diamond Bar per capita income is derived form the 1990 average household Income (Urban Decision Systems, Inc.). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-13 Table II -1-12 Taxable Sales Per Capita 1990 3rd Quarter Business Type Arcadia Cerritos Covina Diamond Bar Apparel Stores 205.53 283.30 35.20 7.15 General Merchandise 477.16 1,330.39 499.71 Drug Stores 75.05 37.10 67.00 29.01 Food Stores 196.04 71.71 219.66 96.18 Package Liquor 19.38 7.01 22.06 7.21 Eating & Drinking 250.28 217.22 298.26 155.16 Home Furn. & Appliances 66.33 203.55 63.21 20.98 Bid. Matt & Farm Implmts. 84.20 286.51 307.38 26.76 Auto Dealers & Supplies 146.57 1,824.47 602.59 95.69 Service Stations 146.99 139.58 215.20 168.86 Other Retail 212.96 834.07 383.41 141.60 Total All Retail 1,880.49 5,234.92 2,713.68 748.68 Other Outlets 367.80 1,400.08 388.04 159.30 TOTAL ALL OUTLETS 2,248.29 6,634.99 3,101.72 907.90 Per Capita Income 1 21,319.00 15,281.00 15,421.00 20,828.00 . General Merchandise for Diamond Bar is included in Other Retail Source: California Board of Equalization, 'Taxable Sales in California,' 1989-1990. 1 Per capita incomes for Arcadia, Cerritos and Covina are from the State Department of Finance, and are adjusted 6 percent per year for inflation since 1987. Diamond Bar per capita is derived from the 1990 average household income (Urban Decision Systems, Inc.) CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-14 Table II -1-13 Taxable Sales Per Establishment 1989 Business Type Arcadia Cerritos Covina Apparel Stores 434.22 683.65 228.50 General Merchandise 7,182.93 16,686.44 7,110.25 Drug Stores 1,030.00 2,034.50 739.64 Food Stores 1,091.00 1,063.36 1,087.97 Package Liquor 261.00 386.50 290.15 Eating & Drinking 515.27 495.89 315.66 - Home Furn. & Appliances 264.14 1,858.92 287.68 Bld. Mat'I & Farm Implmts. 990.86 4,363.46 2,346.50 — Auto Dealers & Supplies 1,438.06 18,578.59 3,108.74 Service Stations 1,203.86 1,205.33 1,199.25 Other Retail 272.39 847.88 416.24 Total All Retail 684.99 2,275.09 849.89 Other Outlets 81.15 263.92 42.96 TOTAL ALL OUTLETS 292.53 875.23 241.51 - Establishments 1,634 1,441 2,202 Source: California Hoard of Equalization, `Taxable Sales in California', 1989-1990. 1 All amounts are in thousands of dollars except the number of establishments. No data was available for Diamond Bar in 1989. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-15 All amounts shown are in thousands of dollars except the number of establishments. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT .lune 8, 1992 11-1-16 Table II -1-14 Taxable Sales Per Establishment 1990 1st Quarter Business Type Arcadia Cerritos Covina Diamond Bar Apparel Stores 91.40 158.07 53.50 29.92 General Merchandise 1,233.82 3,374.83 1,686.83 Drug Stores 278.75 613.25 188.4 339.50 Food Stores 281.74 326.69 287.27 406.56 Package Liquor 69.73 82.50 72.31 60.13 Eating & Drinking 99.82 126.9 80.63 100.08 - Home Furn. & Appliances 64.93 401.64 77.14 35.83 Bld. Mat'l & Farm Implmts. 211.16 1,038.69 473.96 83.45 - Auto Dealers & Supplies 361.00 4,921.50 674.29 616.67 Service Stations 238.35 295.09 285.46 557.23 Other Retail 46.14 141.00 92.71 102.08 Total All Retail 140.90 565.02 201.58 150.71 Other Outlets 31.37 72.94 10.22 11.41 TOTAL All OUTLETS 70.17 217.71 57.19 45.70 Establishments 1,643 1,448 2,204 1,121 • General Merchandise for Diamond Bar is included in Other Retail. Source: California Board of Equalization, 'Taxable Sales in California', 1989-90. All amounts shown are in thousands of dollars except the number of establishments. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT .lune 8, 1992 11-1-16 Table II -1-15 Taxable Sales Per Establishment 1 1990 2nd Quarter Business Type Arcadia Cerritos Covina Diamond Bar Apparel Stores 124.12 183.34 65.86 32.38 General Merchandise 1,487.00 4,066.89 1,832.42 Drug Stores 214.31 468.25 154.40 252.00 Food Stores 262.31 280.54 274.21 372.63 Package Liquor 67.00 93.50 73.08 58.38 Eating & Drinking 103.42 128.82 83.73 115.21 Home Furn. & Appliances 70.24 455.72 85.14 42.92 Bid. Mat'I & Farm lmplmts. 206.16 1,223.92 562.65 144.27 Auto Dealers & Supplies 362.22 5,715.94 749.18 573.33 Service Stations 348.55 295.18 292.71 563.46 Other Retail 53.24 303.55 105.58 92.67 Total All Retail 157.59 642.07 218.45 149.56 Other Outlets 19.17 70.91 11.49 11.61 TOTAL ALL OUTLETS 68.20 238.94 62.29 45.63 Establishment 1,643 1,448 2,204 1,121 ' General Merchandise for Diamond Bar is included in Other Retail. Source: Califomia Board of Equalization, 'Taxable Sales in California', 1989-90. All amounts shown are In thousands of dollars except the number of establishments. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT June 8, 1992 II -1-17 Table U E 16 Taxable Sales Per Establishment 1 1990 3rd Quarter Business Type Arcadia Cerritos Covina Diamond Bar Apparel Stores 116.76 173.37 56.33 25.60 General Merchandise 1,536.13 4,166.47 1,660.85 Drug Stores 226.50 493.75 180.94 311.40 Food Stores 295.84 293.69 287.61 322.63 Package Liquor 62.40 93.25 73.31 48.38 Eating & Drinking 103.30 128.50 80.04 111.04 Home Furn. & Appliances 74.49 373.69 70.03 45.04 Bid. Motl & Farm Implmts. 239.18 1,098.57 577.43 119.67 Auto Dealers & Supplies 4n.", 4,223.26 703.68 642.00 Service Stations 373.58 337.77 371.92 697.15 Other Retail 50.41 290.24 92.55 67.86 Total Ail Retail 156.84 611.20 207.16 138.07 Other Outlets 16.12 72.30 9.85 9.52 TOTAL ALL OUTLETS 64.59 237.56 59.09 40.98 Establishments 1,681 1,487 2,268 1,189 * General Merchandise sales for Diamond Bar are included in Other Retail. Source: California Board of Equalization, 'Taxable Sales in California,' 1989-90. 1 All amounts are in thousands of dollars except the number of establishments. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT II -I-18 June 8. 1992 ISSUES AND OPPORTUNITIES a. Population The City may eventually grow to between 60,000 and 70,000 residents. Development of residential uses in the sphere of influence could significantly increase this estimate. As the City grows, the ethnic diversity of its population will continue 10 increase, although the overall increase will be fairly small. The City will continue io "age" as its population gets older, but it will continue to be a youthful affluent town, home to younger professional families with young children. The percentage of minorities, especially those of Asian decent, will probably increase in the coming years, but no group will experience the dramatic increases seen during the 1980's. b. Housing Housing in Diamond Bar will likely remain largely detached single family units. There will be occasions when the City may want to consider other types of housing such as senior projects or locations where condominiums, townhomes, or apartments are more appropriate because of some preexisting physical or land use constraint. The City may wish to evaluate the potential impacts and costs of additional public improvements on housing affordability, and its associated impacts on new or move -up homebuyers. C. Employment At present the City has approximately 195 acres of developable land designated for retail, service, or office uses. Based on a population of 60,000 residents, the City has just over three acres of commercial uses per thousand population. Diamond Bar therefore provides less land for these uses compared to other (similar) cities in Southern California, such as Anaheim, Fullerton, and Ontario, that provide 5.4 to 7.8 acres per thousand. The City may therefore wish to concentrate on the development of additional commercial uses, as these generate the most additional municipal revenues through sales taxes. For example, a typical new retail commercial center could generate as much as $2 per square foot per year in property taxes and $1 per square foot per year in sales tax revenues to the City. The City should keep in mind however that an emphasis on commercial uses should not exclude thetimely consideration of complimentary businesses or services that will eventually contribute to an appropriate balance of land uses within Diamond Bar. d. Taxable Sales The City has the opportunity to designate vacant parcels of land for uses that would provide additional municipal sales tax revenues. Evidence indicates that retail commercial uses generate the largest amount of sales tax revenues relative to the costs of services they utilize. Office uses essentially break even in terms of costs versus revenues, and business park or industrial uses cost more to serve than the revenues they generate, unless these areas also contain support commercial uses. At present, the City has relatively weak sales in almost all taxable sales categories. Therefore, Diamond Bar could benefit from encouraging most types of commercial businesses. The City may want to periodically examine sales tax revenue data to determine which uses cause the most "leakage" out of the community. Various methods can then be utilized to attract such uses into Diamond Bar, such as reducing or eliminating any processing or permit fees on new businesses of - this type. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENT ASSESSMENT II -1-19 June 8, 1992 J. CRIME AND PREVENTION SERVICES EXISTING SETTING a. Local Crime Due to Diamond Bar's recent incorporation, there is very little historical information on local crimes with which to predict future trends. Statistics on crime within the City's boundaries and sphere of influence have only been kept for only a little over a year. As shown in Table II -J-1, most major crimes appear to have'remained at a fairly constant but manageable level, according to the local Sheriff's Department (McCowen 1990). Diamond Bar presently has fewer major crimes than other suburban cities of similar size in Southern California (see Table II -J-1). Comparable cities include Buena Park, Cerritos, Chino, Corona, Mission Viejo, and Upland. In 1989, the City had 1,897 total major offenses, which is less than half (49 percent) of the median value for total offenses in the 18 comparable cities during the some period. The most common crimes in the City involve theft or assault, which are typical of suburban neighborhoods in the Los Angeles basin, especially those situated along freeways (McCowen 1990). b. Police Facilities Crime prevention and protection services are provided to the City of Diamond Bar by the Los Angeles County Sheriff's Department. The City and its sphere of influence are served by the Walnut/San Dimas Regional Station, which also serves the cities of Walnut and San Dimas, among others. The Walnut Station is located at 21695 East Valley Boulevard in Walnut. It occupies 32,000 square feet with an additional service building of 5,800 square feet. C. Staffing The Walnut/San Dimas Station has a total of 66 vehicles with 40 marked (black and white) patrol cars. The City of Diamond Bar currently has 6 marked patrol cars and one Community Services Officer vehicle specifically assigned to it. The station is approximately 2 miles from downtown Diamond Bar (Grand/Diamond Bar Boulevard) with at least two patrol cars always available within the City limits for emergency calls (McCowen 1990). The Walnut Station presently houses 275 personnel with 150 sworn officers. The City of Diamond Bar now has 18 patrol cars assigned to it, and approximately 29 deputies assigned to it. The Department also provides slightly over three (3.2) full-time detectives, two (2) community service officers, approximately one full-time (0.8) S.A.N.E. (drug prevention) officer, one (1) crime prevention deputy, and a half time (0.5) crime prevention sergeant for Diamond Bar. In addition, one lieutenant and one sergeant have collateral management and supervision of City patrol services (McCowen 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -J-1 Table II -J-1 Local Crime Statistics Source: 'Walnut -San Dimas Stations, First Year and Quarter Reports', Los Angeles County Sheriff's Department. 1990. 1 Based on 'National Crime Statistics' published annually by the Federal Bureau of Investigation (FBI), 1989, Table 6. There are 18 suburban cities in Southern California that are 'comparable' to Diamond Bar (population 55-70,000). Only major crime statistics are kept. 2 Driving while Under the Influence of alcohol or narcotics. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -J-2 Annual Median Crimes for 1988-89 1989-90 1989-90 Comparable Crime 1st Quarter 1st Quarter TOTAL Cities Major Crime Homicide 0 0 2 4 Rape 0 1 10 16 Robbery 14 24 69 181 Assault 62 57 207 269 Burglary 114 128 381 840 Theft 175 179 766 1,791 Grand Theft Auto 101 95 451 750 Arson 5 2 11 24 Subtotal 471 487 1,897 3,875 - Other 615 512 2,241 Vandalism 113 113 474 Total Arrests 221 220 864 Juvenile (%) 10% 21% 17% Traffic Accidents 178 136 722 Fatal 1 0 1 Injury 53 40 207 Property Damage 124 96 514 Citations 3,345 2,531 12,352 Hazardous 2,580 1,335 8,761 Non -Hazardous 169 159 757 Parking 596 752 2,844 DUI2 57 35 193 Source: 'Walnut -San Dimas Stations, First Year and Quarter Reports', Los Angeles County Sheriff's Department. 1990. 1 Based on 'National Crime Statistics' published annually by the Federal Bureau of Investigation (FBI), 1989, Table 6. There are 18 suburban cities in Southern California that are 'comparable' to Diamond Bar (population 55-70,000). Only major crime statistics are kept. 2 Driving while Under the Influence of alcohol or narcotics. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -J-2 Current patrol services in the City include a total of seven (7) personnel for general law enforcement, with 2-3 officers per shift. There are also seven (7) officers for traffic enforcement, again with 2-3 assigned per shift. It should be noted that current FBI and other law enforcement agencies recommend from 1.4 to 2.0 sworn officers per thousand residents for typical suburban communities (Planning Network 1990). With a present staffing of approximately 29 patrol officers, Diamond Bar now has a service level of 0.5 sworn officer per thousand residents (based on an estimated population of 60,000). Staffing Diamond Bar to the minimum recommended level (1.4 officers) would require an additional 55 officers (84 total officers). While this would be more than double the present staffing, these ratios are only suggested, The Sheriff's Department indicates "this level of staffing to be adequate for the current requirements of the City of Diamond Bar" (McCowen 1990). d. Response Times Response call data from the Sheriff's Department indicates an average of 1,250 calls for service each month. The current response time for emergency calls is 4.5 minutes, compared to the Department's goal of less than 5 minutes. The current response time for routine calls is 9 minutes, compared to a goal of 20 minutes (McCowen 1990). These goals are generally consistent with those recommended by the FBI and other law enforcement agencies. e, Community Programs The Crime Prevention Office has a variety of programs to combat crime within Diamond Bar. The primary community crime prevention program is the Neighborhood Involvement Program (in some areas called Neighborhood Watch), which presently has 141 block leaders throughout the City. The Department also presents regular classes on drunk driving awareness (Sober Graduation) at Diamond Bar High School. The Crime Prevention Deputy for the City also publishes weekly and monthly articles in local newspapers. Members of the Crime Prevention Unit also speak to and attend community group meetings on a weekly basis. "The Country" Along the eastern border of the City is the 1,250 -acre gate -guarded "The Country" community. This 16w density development was created in the 1960's with a distinct rural atmosphere. It has no sidewalks or streetlights, and is situated on rolling hills around an oak and walnut studded canyon that drains into Tanner Canyon. Crime in this area is generally low, due to its being guarded and gated. However, these conditions do not preclude the possibility of serious crime. In fact, their presence can lull property owners into a false sense of security. Professional criminals can sometimes take advantage of this because residents do not take adequate security precautions to protect themselves and their belongings. 2. ISSUES AND OPPORTUNITIES a. Future Service As the City grows and changes, the rate, distribution, and types of crimes committed in the City will likely change as well. The service contract with the Los Angeles County Sheriff's Department should be reviewed regularly to be sure the City is receiving adequate protection service. Crime data should be monitored for any rapid changes in types of crimes, as this might signal the need for patrol or other service changes. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June S. 1992 11- 1-1 The City may also want to discuss the Sheriff's Department and the California Highway Patrol utilizing the some radio frequencies so they can "back each other up" in case of a major crime situation. Development of the sphere of influence will require additional security service and personnel, although the actual amount of increased Sheriff's service will depend on the types of uses ultimately approved. Additional roads will require additional traffic patrol, but will generate additional revenues through increased citations. Any significant amount of residential building in the sphere (or elsewhere in the City) will generate a need for additional protective services. b. Community Programs The City may wish to consider how to best advertise and cooperate effectively with the Sheriff's Department and the local school districts on prevention programs for drug and alcohol abuse, safe driving, bicycle safety, child assault prevention, etc. The City may wish to strongly encourage residents and employers to participate in the "Neighborhood Improvement Program" or similar programs through the Sheriff's Department. This also includes "The Country" development. This is a major way local citizens can help reduce potential crime in the City. The City may also wish to institute a crime prevention hotline or a "We Tip" program. Some cities have even included rewards for the apprehension and conviction of criminals through this program. C. Design Measures for Crime Prevention The General Plan can present opportunities to discourage burglaries and other crimes through strategic use of design features. Since burglary is more off en a crime of opportunity than a premeditated crime, community design features can often be implemented to reduce crime incidents. This is commonly referred to as the "defensible space" concept. Defensible space permits the identification of suspicious happenings or persons (in part by increasing visibility and recognition by neighbors), and makes if evident to a potential criminal that a crime could be observed and the criminal easily apprehended. .Unfortunately, it is often difficult to achieve defensible space in hillside developments. Isolated residences or houses not visible from the street or neighbors' houses are more likely to attract criminals intent on theft or vandalism. There is also evidence to support the contention that gated, even guarded communities, are not totally safe. Several instances in the past few years in exclusive developments in Newport Beach showed local residents and police that care and vigilance must be exercised, even in "safe" communities. Similar defensible space techniques and other security precautions can also be defined for other (non-residential) types of uses. In addition to creating defensible developments, road improvements can be made that may reduce the number of hazardous, non -hazardous, and parking violations that occur within the City. Uniform road widths and signalized intersections can minimize the potential for moving violations. Furthermore, provision of adequate off-street parking in commercial areas and near public facilities can minimize parking violations. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 1144 d. City Police Force It is commonly assumed that as a city reaches some threshold population, it becomes cost effective to establish its own police force. Diamond Bar may wish to prepare a study to determine at what size it cold successfully support its own police force. However, the trend within the Los Angeles County Sheriff's Department service area has been just the opposite. Almost a dozen cities have abolished their own police forces in favor of contracting with the Sheriffs Department since 1970, with most of these coming after the passage of Proposition 13. It is anticipated that present fiscal constraints could accelerate this trend. Typical cost estimates show that City police forces generally operate at $140 - $180 per capita, while the County can operate its Sheriffs Department at .approximately $70 -per capita. Regardless of what authority provides protection services, it may be necessary to plan for a substation as the City's population continues to grow. This need could become even more critical if the sphere of influence is developed with uses that introduce new residents or employees. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 1145 K. FIRE HAZARDS AND PROTECTIVE SERVICES EXISTING SETTING a. Fire Threat in Natural Areas The City of Diamond Bar and its sphere of influence contain various materials, both natural and man-made, that are susceptible to damage or destruction by fire. Many of the undeveloped as well as disturbed slopes in the City and native vegetation in Tonner Canyon consist of coastal sage plants which are quite flammable. Some of these slopes also support chaparral vegetation, which has evolved to require occasional burning; plant communities that demonstrate this characteristic are called "fire periodic". In addition, portions of the City and its sphere of influence contain extensive riparian oak and walnut woodlands. While this vegetation is not readily susceptible to fire (because of the amount of water present), the large amount of weedy material could ignite given a fire that was large enough or hot enough. Most fire prevention agencies encourage or utilize firebreaks or fuel breaks in areas with extensive native vegetation susceptible to fire. A fuel break is an area, usually a long strip of land, where vegetative fuels are eliminated or reduced in volume and maintained so as to produce a reduction of fire intensity if a wildfire burns into it. b. Fire Threat in Developed Areas Within the developed portions of the City, there are only minor fire hazards. However, the increase in human activity in an area alone will proportionately increases the chances for accidental fires. Man-made structures within the City can be threatened by fire, depending on their use, construction, and condition. Buildings that present more than a normal level of threat from fire are generally older wood frame structures, especially if they are abandoned or in a state of disrepair. Within the City, the most fire prone buildings are older single family or multiple family structures. Another factor that increases the risk of fire is the use of older single family homes for commercial uses, especially those that utilize combustible materials (paints, solvents, fuels, etc.). Specific building characteristics that increase the risk of fire include open stairwells; lack of firewalls or fire doors; no sprinkler systems in non-residential buildings; worn or substandard electrical wiring, flammable furniture and furnishings, older air conditioning, heating, and ventilating systems. In addition, unsafe practices, such as inappropriate storage of flammable materials, also contribute to the threat of fire. While individual "fire prone" buildings represent a potential safety hazard, collections of these buildings represent a more serious threat to public safety. This is because their burning could produce a large, intense, urban fire that could, in turn, threaten nearby (normally safe) structures. Single family residences are the most common source of urban structural fires; they are also the source of many unsafe practices that cause fires, such as smoking in bed or falling asleep while smoking, kitchen fires from the ignition of cooking oil, or children playing with matches or fireworks. Non-residential uses such as stores, offices, and industries, also represent potential fire threats, especially when they store or use flammable materials. Facilities that handle hazardous, toxic, or explosive materials on a regular basis, such as paint stores and some of the local industries, could represent serious potential fire threats if accidents were to occur at these facilities, In addition, tanker truck accidents on the 57 or 60 freeways represent additional potential fire hazards. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -K-1 Public facilities such as churches, schools, theaters, restaurants, etc. are a special category of fire -threatened structures. Fires at these locations could threaten large numbers of persons, by the nature of their use. But, because of their use, these types of facilities generally have more stringent fire safety requirements. However, unsafe practices, disrepair, or vandalism (arson) can still produce a considerable threat even to well-designed structures, The interrelationship between urban and undeveloped areas is also important in determining overall fire danger. Since the local plant communities have moderate combustibility, it is possible that a major firestorm would proceed through the sphere of influence from Orange County and threaten homes in Diamond Bar. Some increased risk may be found where urban or rural development is adjacent to native -coastal sage or dense chaparral vegetation, or during times of high wind conditions. C. Santa Ana Winds Extreme wind conditions and wildfires have resulted in the loss of life and property in the Diamond Bar area in the past. Generally, winds in the east San Gabriel Valley are from the south and southwest, with an average speed of 11 miles an hour. However, Santa Ana wind conditions are a reversal of the normal winds and occur in late summer and early fall. These warm, dry winds flow from the higher desert elevations and travel through mountain passes and canyons. As a result, wind velocities can reach 90 to 100 miles an hour in the mouths of canyons, dissipating as they spread across the valley floor. The Santa Ana winds generally coincide with dry periods, exacerbate already dry vegetation and make the Diamond Bar area especially susceptible to fires. Once a fire has begun, these high winds aggravate existing fires, not only by spreading the fire quicker, but by blowing hot embers to homes and nearby locations, causing spot fires. d. ISO Ratings The Insurance Service Organization (ISO) is a private insurance research group that periodically assesses the degree to which fire threatens geographic areas. This rating is based on the type of vegetation or structures present, climate, and the availability of fire protection services. The ISO uses a scale of I (best protection or lowest threat) to X (least protection or higher threat). At present, the City of Diamond Bar has an ISO rating of III. However, the sphere of influence has an ISO rating of IX -X, depending on the proximity to water. While these ISO ratings are unacceptable for suburban areas, they are appropriate given the low intensity and type of uses presently within Tonner Canyon. The ISO also rates fire departments on the some scale according to their ability to provide the protection. At present, the Los Angeles County Fire Department (LACFD) has an ISO rating of III within the City, which is considered good for urban areas. However, similar to the ISO rating for Tonner Canyon, the LACFD can only provide adequate (ISO Class III) service within five miles of its stations and where fires are within 1,000 feet of an hydrant. Due to staffing, personnel, and facility limits, the LACFD cannot at this time provide suburban level fire service to the sphere of influence at this time. However, unless this area develops to suburban/urban intensities, this level of protection is not needed. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -K-2 G. Fire Protection Services The Los Angeles County Fire Department (LACFD) provides fire protection services to much of the east San Gabriel Valley, including Diamond Bar and its sphere of influence. The LACFD was formed to provide both wildland and structural fire protection. The City of Diamond Bar contracts with the County of Los Angeles for the same level of staffing and protection normally provided to other largely developed but unincorporated areas. During 1989, the LACFD responded to 116 fire -related calls in Diamond Bar (Gee 1990). The LACFD maintains three fire stations in the immediate area to serve Diamond Bar. Their locations are shown in Figure II -K-1, and their equipment and staffing are presented in Table II -K-1. Station 119, located on Pathfinder Road near Brea Canyon Cutoff Road, serves the southwestern quarter of the City, essentially all areas west of Pathfinder and Diamond Bar Boulevard. Station 120 is located on Grand Avenue just west of Diamond Bar Boulevard. This central station serves the majority of Diamond Bar, and overlaps service areas with the newest station (# 121). Station 121 is located just south of the 60 Freeway on Armitos Place and serves the northern portions of Diamond Bar, as well as portions of the Phillips Ranch and Pomona. There is also a fire station in the "downtown" area of Phillips Ranch operated by the City of Pomona Fire Department. The Walnut Valley Water District has made ample provisions in its current distribution storage program to provide sufficient storage for required fire protection. The District's five-year goal (1995) is to provide 67 million gallons (a three day supply) of in -District storage. Only two small portions of the City are outside of the recommended LACFD fire station service radius of 1.5 -miles (see Figure II -K-1). The first is the industrial area near Brea Canyon Road and Lycoming. However, this area is just outside of the recommended service area for both stations 119 and 120 within Diamond Bar. However, it is within a 2 -mile radius of both stations, which is still considered acceptable in suburban locations. It is also within 2 miles of a third station (#61), located in Walnut at the corner of Puente Road and Lemon Avenue. The second area outside of the recommended 1.5 -mile fire station service area is the southeastern portion of "The Country" development. However, this area is also within two miles of both Stations 119 and 120. The locations of and equipment and staffing at these three stations provides all of Diamond Bar (within the City limits) with adequate protection from typical urban fires. Stations 120 and 121 have service areas that total 4.5 square miles of land, while Station 119 has a service area of 5.6 square miles (Freeman 1990). These stations provide a local service level of one firefighter for every 6,500 residents in Diamond Bar (Gee 1990). In the case of a major brushfire, the County maintains automatic mutual aid agreements with other area fire agencies under the State Mutual Aid Pact. These agreements can help augment the resources of local fire districts in the event of a major fire. One agency in particular that has proven extremely helpful during brushfires is the U.S. Forest Service. The USFS maintains a fleet of water- and borate -dropping aircraft to combat forest fires, which are also invaluable in fighting raging brushfires as occur in Southern California periodically. All Los Angeles County Fire Department firefighters have Emergency Medical Technician (EMT) training, and specialized paramedics are provided at Station 119 in Diamond Bar (Gee 1990). For additional information on paramedic and emergency transportation (see Section II -L, Health and Emergency Services and Section II -M, Hazardous Materials. The Department also maintains regular brush -clearing and weed abatement programs (Gee 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .lune 8, 1992 II -K-3 Y m 0 Z L 0 5 0 mJ z Z V g V cz Lu U uo LLJ O�� ��� �0tx Z 'LU D 0- 4. J Z q KI LL LL 0 0 S 0 2 Table II -K-1 Fire Protection Facilities Station Location Equipment 119 20480 Pathfinder Road 5 firefighters, 1 Engine, 1 Rescue Squad 120 1051 S. Grand Avenue 4 Firefighters, 1 Engine, 1 Patrol 121 346 Armitos Street 3 Firefighters, 1 Engine Source: Los Angeles County Fire Department, 1990. 2. ISSUES AND OPPORTUNITIES a. Additional Facilities The Los Angeles County Fire Department (LACFD) attempts to maintain a maximum five minute response time to urban and suburban areas. To this end, the LACFD typically tries to locate fire stations with a urban/suburban service area radius of 1.5 miles. A second guideline for service area is 4.5 to 6 square miles served by each station, depending on terrain and extent of development. A service area of this size can accommodate the fire protection needs of approximately 7,000 dwelling units in an urban area. Based on the City's present household size (3.49 per household), each LACFD fire station should serve approximately 20,000 residents. That means that of buildout (population 75,000), the City might need one additional fire station. While this estimate takes into account total service population, it does not address optimum service area (recommended 1.5 mile radius). Although small portions of the City are outside of this optimum area, they are within acceptable distances from two adjacent stations, and so are considered to have adequate service. Therefore, the City itself would probably not require an additional station. The LA County Fire Department has already indicated it has no plans to build another fire station within Diamond Bar (Gee 1990). The entire Tanner Canyon could require as many as 3 additional stations, since it is about 9 miles long, and each station has a service area diameter of 3 miles. However, the Diamond portion of Tonner Canyon would probably only require one (1) additional fire station. This would be added to the one (1) additional station projected based solely on total population. The ultimate number and location of fire stations will depend on how the City and its sphere of influence build out, where land uses are located, and to what density they are built. At this point, it appears that fire facilities to serve buildout of the City already exist. However, development of the sphere of influence may require an additional fire station. The LACFD tries to plan one headquarters station for each four to six engine companies. The Department also has a service standard of one rescue squad for every three engine companies, and one truck company for every four companies. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .June e, 1992 II -K-5 At present, it costs the County at least $1 million to construct a new, single-engine company fire house, not including land costs. It costs an additional $1 million annually to equip, staff, and operate such a facility. If development of the sphere of influence required one (1) new fire station, at a minimum, the County would incur a capital cost of at least $1 million, not including land costs or any additional headquarters stations. It would also incur an increased operating cost of at least $1 million each year after the sphere was developed. b. City Fire Department At some threshold population, it is popularly considered cost effective for a City to provide its own fire protection service as opposed to contracting with the County. This approach is off en attractive for cities that wish to establish or maintain their own identity, separate from the County, and to exert local control over fire service. However, historical trends within the LACFD service area indicate that the opposite is more prevalent. Over the past twenty years, almost a dozen jurisdictions that previously operated their own fire departments began contracting fire services from the County, and abolished their own fire departments. The biggest reason for this conversion is simple economics; use of the larger LACFD allows greater economies of scale (i.e. less expensive) while maintaining service levels. It has become increasingly expensive for small cities, and even large cities, to purchase and maintain the equipment and personnel needed to provide adequate fire service. It is generally two to three times cheaper to utilize LACFD services compared to a City operating its own service. The only instance where this ratio would not hold would be isolated areas with no adjacent County fire services. However, it would probably still be cheaper to utilize County services as opposed to a separate City service. It would therefore not be in the best interests of the City to pursue formation of a separate City Fire Department, although the City may wish to study the economics in more detail at a later date. C. Home Protection The City may wish to encourage residents to protect their properties through the use of fuel modification, landscape design, or other measures. The following publications, among many others, may be helpful in educating residents on home fire protection methods: Los Angeles County Department of the Forester and Fire Warden: "Drought Tolerant Landscaping", 1979. "Oak Trees: Care and Maintenance", 1988. "Vegetation Management in the Wildland-Urban Interface of Los Angeles County", 1989. "The Eucalyptus Longhorn Beetle: Prevent the Spread of This Pest", 1989. "Fire Hazard vs. Erosion Control", 1989. Sunset Magazine (Lane Publishing Company): "Protecting Your Home Against Brushfire", September 1985. "Saving Our Oaks", October 1990. United States Forest Service: "Homeowner's Guide to Fire and Watershed Safety at the Chaparral/Urban Interface", January 1990 (4th printing -revised). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -K-6 L. HEALTH AND EMERGENCY SERVICES EXISTING SETTING Diamond Bar residents face potential harm from accidents and disasters. Every day, people need various kinds of medical care to continue enjoying the quality of life in Diamond Bar. In addition, a major disaster, such as a brushfire or earthquake, could seriously disrupt community life for many months. a. Accidents Wherever there is human activity, there is the potential for property damage, bodily injury, or even loss of life due to accidents. Accidents contribute to lost productivity, both economically and socially, and to staggering health care costs that are ultimately borne by society as a whole. While most accidents are minor, many situations can be life threatening unless adequate emergency care is available. A variety of other ongoing health programs are also necessary for prevention of serious diseases. Early diagnosis and successful treatment are more likely with regular checkups and appropriate facilities nearby. While a General Plan cannot eliminate injuries to its citizens caused by accidents, it can determine if there are adequate health care facilities and services available to its residents to minimize the potential for catastrophic loss. b. Local Health Care The provision of health services in California is monitored by the Office of State-wide Health Planning and Development (OSHPD), a joint State agency review board. Diamond Bar is located within Health Service Area (HSA) 11, which covers all of Los Angeles County. HSA 11 is further divided into smaller Health Facility Planning Areas (HFPAs). Diamond Bar and adjacent portions of the cities of Walnut and Pomona are included in HFPA 917 (Pomona). According to the California State Health Plan (OSHPD 1989), there are five major hospitals in the east San Gabriel Valley area that serve Diamond Bar. Of these, four are located in Pomona, (American, C.P.C. Horizon, Pomona Valley, and Valley Hospital) approximately three miles northeast of Diamond Bar. According to local records, there are at least twelve additional health care facilities within a seven mile radius around the City. Due to the City's location, some of these other "local" (non-HFPA) hospitals are located in other counties (Orange or San Bernardino). These facilities are also listed in Table II -L-1. As of 1988, there were no County -operated hospitals located within the Pomona HFPA. The State Health Plan indicates there should be adequate health care facilities and programs in this area through the year 2000. Local facilities can maintain adequate occupancy levels by continuing to provide quality service at affordable rates. There are also a myriad of private medical centers and clinics in the East San Gabriel Valley that together provide a comprehensive array of specialized medical services, including 24-hour emergency treatment. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -L-1 Table I -L-1 Local Hospitals Hospital Ownership) #f Beds Use (%) Location Distance from City2 IN POMONA HFPA (917) City OUTSIDE OF POMONA HFPA American NA NA NA Pomona 3.5 mi. NE Casa Colina Rehab Center Pb 66 69 Pomona 3.3 mi. NE C.P.C. Horizon Pr 79 67 Pomona 4.0 mi. NE Lanterman - Psycho. Center St 1286 83 Walnut adjacent Pomona Valley Community Pb 389 77 Pomona 2.7 mi. NE San Dimas Community Pr 99 54 San Dimas 5 mi. NW Valley Hospital - Pomona Pr 18 12 Pomona Hospital Address - Location Distance from City OUTSIDE OF POMONA HFPA Los Angeles County Queen of the Valley 1115 S. Sunset Avenue W. Covina 6.2 mi. W Inter -Community 303 N. 3rd Street Covina 7.0 mi. NW AMI San Dimas 1350 W. San Dimas BI. San Dimas 5.0 mi. N Doctors Hospital 725 S. Orange Avenue W. Covina 7.0 mi. NW San Bernardino County4 Chino Community 5451 Walnut Avenue Chino 4.4 mi. E Orange County Facilities4 Brea Hospital 875 N. Brea Blvd. Brea 2.8 mi. SW Brea Community 380 W. Central Avenue Brea 3.5 mi. SW St. Jude Fullerton 7.0 mi. SW Fullerton Community Fullerton 6.6 mi. SW Placentia -Linda Placentia 6.8 mi. S Source: 'Califomia State Health Plan', Office of State-wide Health Planning and Development, 1989. 1 Pb = Public Pr = Private St = State NA = Not Available 2 City and/or County.. 3 As reported in the Califomia State Health Plan, Supplement XI, Po Pp Appendices, 1989. 4 Within seven miles (equals driving 20 minutes on city sheets @ 35 mph). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -L-2 C. Paramedic Service The Los Angeles County Fire Department presently provides paramedic service to the Diamond Bar area. All County firefighters have Emergency Medical Technician level 1 (EMT -1) training. There are also specific paramedic personnel housed at Station 119 in Diamond Bar, as well as Stations 61 and 118 in Walnut. Additional paramedic resources are available from the Paramedic Assessment Engine 120 (Gee 1990). Average response times are less than five minutes throughout the City, while emergency response times are often less than two minutes. If needed, the County Fire Department will expand fire protection service (including paramedic staffing) as the City's population grows. The 1989 State Health- Plan indicates that the Pomona HFPA within which Diamond Bar is located had 31 Basic Treatment Stations for Emergency Medical Services in 1987, and was projected to need only 17 stations (total) by the year 2000 (OSHPD 1989, Supplement VIII). d. Ambulance Service At present, the Los Angeles County Fire Department contracts with several ambulance Emergency Services to provide emergency medical transport service within the Diamond Bar area. Emergency (911) calls are screened by the Fire Department, and ambulance vehicles are routed as necessary. Under the County contract, the ambulance service responds to all medical emergencies and transports the injured to local hospitals. They then bill for service to relieve costs, with the County providing a portion of the cost the individual cannot afford to pay. e. Airborne Evacuation The County Sheriff's Department maintains a helicopter fleet for aerial surveillance, which can be also used for transport in a medical emergency. Emergency transport is also available by helicopters stationed at hospitals in the Los Angeles area. Response times vary from 20-40 minutes, except during inclement weather. In addition, the Los Angeles County Fire Department has an air ambulance service which is available routinely if an emergency warrants. This air ambulance is also staffed with two paramedics. Major Emergencies and Disasters Natural disasters include fire (except arson), flooding, winds, earthquakes, etc. Examples of man-made disasters might include a major traffic accident (usually on the freeway), especially if it involves hazardous materials, or arson fires. According to the State Office of Emergency Services (OES), disasters are often defined as "major accidents or natural acts affecting a large number of people or structures". OES considers a major earthquake along the San Andreas Fault to be the most serious potential threat facing Southern California in the next 20 years (CDMG 1982). This is because such an earthquake would have tremendous destructive potential, would come without warning, and could overtax all local and regional relief agencies simultaneously. For those reasons, a major earthquake is typically used as the ultimate disaster planning scenario. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -L-3 g. Earthquake Planning Scenario In 1982, the California Department of Mines and Geology prepared a major earthquake study for the Governor's Emergency Task Force on Earthquake Preparedness. This study is still considered the most comprehensive and relevant earthquake planning study for southern California, and was based on an 8.3 Magnitude earthquake on the southern San Andreas Fault. Depending on the time of day and what day the earthquake occurs, the study estimates the following impacts to Southern California: • 3,000 to 14,000 deaths; • 12,000 to 55,000 injuries; • Several billion dollars in damage and property losses; • Restricted regional freeway access from overpass collapse and mass evacuation efforts; • Severely limited emergency services, including police and fire service, due to widespread destruction and fires; • Damage to hospitals and other health care facilities, and severely limited medical services due to destruction and widespread injuries; • Loss of utility services such as electricity, water, and natural gas; • Damage to utility lines including electricity, natural gas, water, and sewer; • Local fires and damage caused by explosions and fires from natural gas leaks; • Possible separation of family members for up to 5 days; and • A period of 3-5 days that families and businesses will have to be largely self- sufficient until State and federal resources can be organized and delivered to the area. h. Local Disaster Impacts The City of Diamond Bar will also suffer various injuries, possibly even deaths, and property damage from a major earthquake. The City is in an area expected to receive "strong shocks". A 20 -inch petroleum pipeline next to the San Jose Creek can be expected to rupture as a result of sever groundshaking. The 57 and 60 freeways are expected to be open, but travel will be subject to delays and/or detours. Major accidents may also occur on the freeways as a result of panic or loss of vehicle control. Railroad lines will be damaged, and train cars in the area may be overturned and their contents spilled. Telephone service may not even return to 50 % performance by three days after the earthquake. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -L-4 If the earthquake occurs during the day, children may be at school or day care programs, and may be separated from their parents for 3-5 days. How long they are separated will depend on: If parents survive the earthquake, and How soon they can reach the facilities to pick up their children, Homes may be damaged or destroyed, especially in areas with unstable or weak soils. The earthquake may also trigger secondary effects in the City such as liquefaction, landslides, or movement of local faults. i. Disaster Coordination During a regional disaster, the City will coordinate its activities and make requests for aid through the County Emergency Operations Center (EOC) in downtown Los Angeles. Most cities already have adopted procedures to follow in responding to emergencies such as flood, fire, earthquake, hazardous material spills, etc. Evacuation Routes During a major disaster, people tend to evacuate to family members homes (if their houses are damaged but they are uninjured), to local hospitals if they are injured (and can drive), or to mass care shelters if they know where they are located. Local emergency facilities have been discussed previously under hospitals. It should be noted that each of these facilities has established a disaster plan to continue operating during a major emergency. Local volunteers with the American Red Cross can establish shelters fairly soon after a major disaster. 2. ISSUES AND OPPORTUNRIES a. Health Care Facilities As the City grows, there may be a need for a hospital located in Diamond Bar. A full-service local hospital would make health care more accessible and convenient for local residents, especially for emergency room treatment. Even having a variety of specialized health care facilities would benefit local residents, especially the elderly. Local hospitals may wish to join a joint benefit association with the County Fire Department and/or the County Sheriff's Department to provide local emergency helicopter service. This may become necessary as development extends into the sphere of influence, and beyond the service areas of the existing fire/paramedic stations and the local ambulance company. b. Paramedic/Ambulance Service As the City grows, additional paramedic and eventually ambulance services will be needed. As long as the County maintains its existing staffing levels for paramedics and contractual arrangements for ambulance services, there will be adequate emergency services to area residents. No separate fees for service are anticipated at this time (Gee 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -L-5 C. Disaster Preparedness The City has already taken the first step in disaster preparedness with the designation of a disaster coordinator on staff. The City has established an Emergency Operations Center (EOC) at the Civic Center to be activated in case of a major emergency. City services can then be coordinated during major emergencies with other local and regional service agencies. During a disaster, this centralized command center will house personnel from the Fire Department, Sheriff's Department, City departments, Highway Patrol, Red Cross, and other appropriate representatives. Mass care shelters (usually high schools) are designated in conjunction with the Red Cross and local school districts. The City has also purchased its own portable communications system to allow coordination of City,personnel and activities during local or regional emergencies. To adequately prepare for disasters, the City may wish to work closely with local agencies, especially the school districts, to assure that there will be adequate public services during major emergencies. Coordinated efforts will help to avoid mass confusion and panic that can cause or increase the disaster. The City may wish to encourage workers and residents to become Red Cross volunteers, as this will increase the number of trained individuals available during emergencies. The City may wish to offer or encourage citizens to take courses on safety and disaster preparedness, such as those offered by the Red Cross, and to make their homes and businesses safe from accidents and disasters. The City may wish to provide materials for the public and encourage public awareness on disaster preparedness. Such materials may include but not be limited to the following: • "Be Prepared -Diamond Bar Emergency Preparedness (Steps to Take)", 1990. • "Beat the Quake" by the State Office of Emergency Services • "Safety Tips for Earthquakes" by the Federal Emergency Management Agency • "Preparing for Emergencies" by the Orange County Fire Department • "Emergency Supply Checklist" from the American Red Cross d. Evacuation Routes The possibility of a major disaster requires careful planning of evacuation routes. The unpredictability of the impact of any disaster on existing streets and highways makes definite evacuation route designation impossible until a disaster actually occurs and damage is assessed. However, assuming that major streets and freeways are functional, the major evacuation routes would be the 57 and 60 freeways, and Grand Avenue. Secondary routes would include Diamond Bar Boulevard (north to Mission), Brea Canyon Road (south to Orange County), and Golden Springs Drive (both west to Colima Road and north to Turner Avenue). The City may wish to make citizens aware of these routes and other information they might need relative to safe evacuation. Additional evacuate routes may have to be designated based on future developrnent, especially as the sphere of influence develops. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 114-6 M. HAZARDOUS MATERIALS 1. EXISTING SETTING Since the City of Diamond Bar has no heavy industry, it could be easily assumed that there is very little danger of a hazardous material incident within the City. However, there are three reasons why this may be a misperception: • The City has many light industrial and other uses throughout the non-residential areas that produce, utilize, or transport a variety of hazardous materials each day; The nearby 57 and 60 freeways conduct thousands of tanker trucks each day; and There are two nearby railroad lines that carry many tanker train cars daily. For example, in December of 1990, a metal storage yard caught fire in the City of Industry. Several stocks of magnesium bars ignited and caused large fire and billowing clouds of irritating smoke. Had the fire been a little closer and the wind been blowing toward the City, Diamond Bar residents would have been affected by this incident. It is therefore possible for a hazardous materials incident to occur in Diamond Bar, even though it is a suburban bedroom community. a. Hazardous Materials The accidental release of any harmful material is a potentially serious public health incident. A hazardous material is defined as any injurious substance, including pesticides, herbicides, toxic metals and chemicals, volatile chemicals, explosives, and even nuclear fuels or low-level radioactive wastes. The use of hazardous materials is commonplace in modern industrial and agricultural activities. Because these materials are increasingly used in urban and rural settings, and because they represent such a serious potential threat to human health and safety, strict laws and regulations have been developed to control their use, storage, disposal, and transport (LACDPW 1987). Hazardous materials can be classified into four general categories: • Explosives • Flammables • Irritants • Toxins Explosives can produce rapid chemical reactions causing damage due to blast and flash fire. Flammables are dangerous because of their low ignition temperature and rapid burning characteristics. Some flammable materials burn so violently that they cannot be extinguished, and must be allowed to burn out naturally. Irritants can cause inflammation or destruction of living tissue with effects ranging from mild to severe, based on the degree of exposure and type of material involved. Because of their widespread use, many types of hazardous material are transported through,.used, or stored to some degree, within the City of Diamond Bar. Toxins include various poisons which are harmful or fatal if swallowed, inhaled, or ingested through the skin. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -M-1 b. Road Transport The transport of hazardous materials by truck or rail is regulated by the United States Department of Transportation through National Safety Standards. The federal safety standards are also included in the California Administrative Code, Environmental Health Division. The California Health Department regulates industrial hazardous waste haulers only. Both the 57 and 60 freeways are major truck routes in and out of the Los Angeles basin, and are classified as hazardous material transport routes by the California Highway Patrol (CHP 1983). In the immediate area, Interstate 10 and State Route 71 are also classified as hazardous material routes. According to this classification, trucks using these routes can also transport explosive materials. There are no "Safe Stopping Places" or Inspection Stops designated by the Highway Patrol within Diamond Bar. The California Highway Patrol (CHP) is responsible for the general enforcement of motor carriers hauling hazardous wastes. There are three basic methods of enforcement. Truck scales issue "compliance ratings', which monitor maintenance, vehicle code, safety, and cargo compliance with federal, State, and local laws. However, there are no truck scales presently in the vicinity of Diamond Bar. The CHP's Motor Carrier Safety Unit conducts inspections at "terminals", which are generally areas or yards where trucks are parked and/or operated from, including school bus terminals, truck stopstyards, etc. In addition, a "Mobile Road Enforcement Program', is employed, which utilizes two officers to patrol roadways with the authority to set up lane inspections on city and county roadways, as well as on State highways. G. Rail Transport A variety of hazardous materials are transported along the railroad lines just west of Diamond Bar. These two spur lines travel between Pomona and Los Angeles; they pass just west of the Lanterman State Hospital, the YMCA Sports Park on Sunset Crossing, and the industrial area near Brea Canyon Road and Lycoming. The line adjacent to the City is a Union Pacific line that is also designated as belonging to the Los Angeles and Salt Lake Railroad. The line further away is operated by the Southern Pacific Railroad (SPRR). Transport of hazardous materials via rail is controlled by State and federal regulations. It is likely that a significant amount of hazardous materials are shipped by rail along these routes each year. d. Airborne Dispersal Both the 57 and 60 freeways carry hazardous materials. The two railroad lines also carry dangerous materials. If an accident were to occur, liquid materials could spill from ruptured tanker train cars or trucks. Some of these materials would volatilize upon spillage into plumes of toxic gas. Since prevailing winds generally blow to the northwest, there would be a "drift zone" immediately west of the 57 or 60 freeways, or west of the railroad lines. These conditions would primarily affect residents and employees "downwind" of such a spill, which would be in the cities of Industry and Walnut. However, an accident on the Pomona Freeway grade between the 57 Freeway and Phillips Ranch Road, could create a potential threat to public health and safety were hazardous materials to be released. It should be noted that, although the prevailing winds may give some protection against airborne dispersal of hazardous materials, significant health hazards could occur if the local wind direction changed to the east during a hazardous materials incident. Presently, no regulations exist that would prohibit houses and public buildings within "drift zones" located along hazardous material transport routes, or even any notification guidelines for local jurisdictions. This Is due to the possibility that routes may change over time and, as a result, liability concerns with building owners may arise. In addition, interstate routes are usually the only routes which must comply with hazardous material regulations (Douglas 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -M-2 The lands east of these two routes include residential or public uses where large numbers of people could congregate. These uses would need time for warning and evacuation in the event of a major hazardous material spill, especially along the SPRR line. The Federal Department of Transportation suggests evacuation up to a half mile away from train car accidents involving the most serious types of hazardous materials (DOT 1980). In general, higher wind velocities can quickly transport an airborne plume a considerable distance downwind, although its horizontal dispersal would be proportionally less. Conversely, low wind velocities disperse a plume more slowly and not as far downwind, but the horizontal dispersal would be proportionally greater. e. Water Dispersal The area contains a number of local watercourses, including Diamond Bar Creek, Brea Canyon Creek, Sunset Crossing Flood Control Channel, etc. A major truck accident or train car spill could enter local channels and represent a health hazard to areas downstream. Storage and Use of Hazardous Materials The City of Diamond Bar is located in one of the largest urban areas of the State of California. Much of its growth has been attributed to residential development, and its associated service sector. Along with this growth, the potential for growth in hazardous materials storage and transportation has increased. Regulations and enforcement of safety measures for the storage and use of hazardous materials is the responsibility of many agencies, including local fire agencies. National, State, and local fire codes act as a guideline for local enforcement (LACDPW 1987). The Environmental Protection Agency (EPA) ensures that containers of hazardous materials are properly labeled with instructions for use. The California Department of Industrial Relations, Cal -OSHA Division, regulates the proper use of hazardous materials. The United States Department of Agriculture, California Department of Food and Agriculture, and the Department of Industrial Relations regulate pest control operations, pesticide dealers, and pesticide users to insure that hazardous agricultural chemicals are properly used. The Los Angeles County Fire Department maintains records on major hazardous waste generators within its jurisdiction, including the Diamond Bar area. It should be noted that the term "major" refers to those handlers that deal with 500 gallons of liquid material, 5,000 pounds of solid material, or 2,000 cubic feet of a gaseous material. As with any area, there are numerous firms throughout the City that presently produce, transport, or utilize hazardous materials of lesser quantities on a daily basis. It is expected that small handlers will continue to be distributed throughout the City, and could become more widespread as the City develops and regulations become more stringent. In addition, the Los Angeles County provides state -mandated underground storage tank regulations within the City, as well as contracted industrial waste services for local enforcement. g. Disposal of Hazardous Wastes Currently, there are no active landfills operating in Los Angeles County which accept hazardous wastes. The nine and one-half million tons of hazardous wastes generated within the County annually which are disposed of off-site are transported to Kettleman Hills -Landfill in Kern County and to Casmalia Landfill in Santa Barbara County. Both facilities are considered to be active "Class One" landfills, capable of handling all types of urban wastes, including toxic and hazardous materials, except explosives and radioactive materials (LACDPW 1987). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -M-3 h. Illegal Dumping The East San Gabriel Valley area is subject to infrequent, illegal dumping of hazardous materials, such as household and commercial wastes. In general, because of the extensive laws governing industrial wastes, local industrial wastes are disposed of properly. However, illegally dumped industrial and domestic wastes are occasionally found in the desert area. While it is believed that the majority of this illegal dumping is from sources in the Los Angeles Basin, there are undoubtedly local sources of this problem as well. Response to Hazardous Materials Emergencies The City of Diamond Bar by itself does not have sufficient resources to deal with a hazardous materials incident. The various tasks associated with control and cleanup of hazardous materials is more regional and multijurisdictional than local, and the majority of the response resources would come from the following agencies outside of the City of Diamond Bar: • The Los Angeles County Fire Department's Hazardous Materials Response Team provides assistance for substance identification, tactical and technical decisions, notification to other agencies, and the establishment of a command post. In addition, all County firefighters are qualified as hazardous materials first responders (Gee 1990). • The Los Angeles County Sheriff provides security, evacuation, and investigation activities along with the coordination of notification, evidence collection, and prosecution actions along with other agencies, in response to a hazardous materials situation. • The Los Angeles County Department of Health Services provides an advisory staff to identify, assess, and control illegal disposal of hazardous waste and referral to appropriate prosecutorial agencies. • The American Red Cross and local schools would coordinate the establishment of mass care shelters, feeding sites, and provide disaster relief services such as relocation assistance. However, a hazardous material Incident in conjunction with a major earthquake would preclude immediate response by some or all of these agencies due to damaged roads and more immediate emergencies (LACDPW 1987). For additional information on earthquake planning, see Health and Emergency Services. 2. ISSUES AND OPPORTUNITIES The City of Diamond Bar may wish to develop a hazardous materials mitigation program as part of a . broader Emergency Preparedness Plan. This plan could be updated on a regular basis to maintain an adequate level of preparedness and ability to respond to a variety of emergency situations, including hazardous material incidents. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -M-4 a. Illegal Dumping Although the illegal dumping of hazardous wastes is not yet a major problem in the City, it could become one as waste disposal regulations become more strict. This is especially true for vacant or undisturbed areas including the sphere of influence. As part of their response to the growing problem of hazardous materials, some cities have established telephone hotlines and offer rewards based on convictions of illegal dumpers. This program could be funded out of a surcharge on business licenses issued by the City, and by fines levied on convicted dumpers. This assessment could be applied to all new businesses, since most, if not all, firms produce, transport, or use hazardous materials of one kind or another. b. Household Hazardous Wastes While there exist extensive laws and regulations related to industrial wastes, the disposal of household hazardous wastes is very difficult to regulate. The typical household over the course of a year will create small amounts of hazardous wastes including paint cans, garden pesticide containers, and other similar materials. In general, these wastes are disposed of in normal household trash, and are thus hauled to landfills which are not certified to accept hazardous wastes. While the amount of hazardous waste created by any individual household is small, the cumulative total of wastes created by the residential sector may be substantial. The City may wish to investigate a joint program with the Fire Department to collect and dispose of household hazardous materials. However, cities maybe able to join the County's "Household Hazardous Waste Plan' which is presently under development (Bohlander 1990). C. Transportation Routes At this point in time, there are few practical alternative routes for hazardous materials through the Diamond Bar area. The railroad lines are the only ones through this area, just as the 57 and 60 freeways are the major direct roadway links to the Los Angeles Basin. If alternative roads or freeway routes are developed, they should be examined for possible use as hazardous material routes. This would include, but not be limited, to extensions of Grand Avenue or Tonner Canyon. d. Land Planning It would be difficult if not impossible to maintain lands adjacent to hazardous material routes (the 57 and 60 freeways, railroad lines) completely clear of houses, businesses, and public buildings. Presently, there are no federal or State regulation setbacks for houses, businesses, or public buildings from hazardous material routes. The main reason for this is because routes may change, and, as a result, liability problems with building owners may arise. Additionally, interstate routes are usually the only routes that qualify for hazardous material regulations (Douglas 1990). However, owners of such facilities should be aware of potential risks and plan accordingly. Where possible, low intensity uses such as open space, multi -use trails, or nurseries could be encouraged. Care should also be exercised to preclude or carefully regulate structures that might concentrate potentially dangerous gases, either natural or man-made. e. Community Information The City may wish to develop a community information program on hazardous materials. The City could provide information to residents and employers living and working near hazmat transport routes, so they could learn about the potential risks of spills and the need to develop contingency and evacuation plans. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT II -M-5 June 8. 1992 - Emergency Planning The City might also choose to work directly with residents and employers along major hazardous material transport routes to develop evacuation plans. Uses along both the 57 and 60 freeways, as well as the railroad lines, could be specifically targeted. The City may wish to consider the time needed for evacuation, the likelihood of a major incident, and the relative safety provided by such plans when determining what areas to notify and/or work with in developing plans. Facilities where the public congregates, such as churches, schools, restaurants, etc., that are within a half mile of these major routes should be notified as to the potential risks due to hazardous material spills. In particular,- the City should work with the Walnut Valley Unified School District to plan evacuation of Diamond Bar High School. This site is located just east of the 57 Freeway and can have up to 2,500 high school students on campus during any given school day. Table II -M-1 lists public facilities within a half mile of the major hazardous material routes in the City. Figure II -M-1 shows the locations of these facilities relative to the hazardous material routes. As shown in Figure II -M-1, there are seven elementary schools, 2 junior high or middle schools, one existing and one proposed high school, five public facilities (including City Hall), and five parks within half a mile of the major local hazardous material transportation routes. g. Waste Facility Siting In addition, the new siting requirements for hazardous waste facilities (under the Tanner Bill) in many ways supersede the historical land use authority of local governments. A detailed but accelerated review procedure is involved via a regional commission. If a proposed facility meets the siting criteria as specified in the County Plan, a local jurisdiction no longer has the authority to deny the application based on incompatibility with the City unless it affects public safety. However, the County's Hazardous Waste Plan does not identify any locations at present for such facilities within Diamond Bar. This is according to the "General Areas Potentially Suitable for Off-site Hazardous Waste Management Facilities' (Figure 1 in LACDPW 1987). According to recent changes in State law, local jurisdictions must now identify potential sites for waste handling facilities. The City should therefore determine areas in the City that are most appropriate for potential hazardous waste facilities. However, the siting and operation of regional hazardous waste facilities are still subject to State review and regulations, which can preempt local land use plans. The City should consider working closely with the County Fire Department to monitor the location and type of local hazardous waste facilities/generators, especially in relation to public or high occupancy facilities. The development review process should include a comparison of these factors prior to the granting of approvals. The City may also wish to develop a policy for facilities that generate a significant amount of hazardous waste. These facilities should require a conditional use permit that must be reviewed annually; such a renewal could be denied if problems developed regarding the handling or production of hazardous wastes. C ITY OF DIAMOND BAR DRAFT MASTER ENV I R ON MENTAL As S E S S MEN T II -M-6 June 8. 1992 Table Il --M-1 Sensitive Receptors Near HazMat Routes' Facility Address ELEMENTARY SCHOOLS Castle Rock 2975 Castle Rock Road Evergreen 2450 Evergreen Springs Road Maple Hill 1350 Maple Hill Road Armstrong 22750 Beaverhead Drive Golden Springs 245 S. Ballena Drive Diamond Point 24150 Sunset Crossing Road Walnut 841 S. Glenwick JUNIOR HIGH/MIDDLE SCHOOLS South Point 20671 Larkstone Drive Lorbeer 501 Diamond Bar Boulevard SENIOR HIGH SCHOOLS Diamond Bar Tres Hermanos •=144. Heritage Starshine Maple Hill Sycamore Canyon Peterson PUBLIC FACILITIES 21400 E. Pathfinder Road Proposed City Hall Walnut Valley School District Office Diamond Bar Golf Course Club House Little League Sports Park Fire Station # 121 0.1 mile east of 57 Freeway 0.4 mile east of 57 Freeway 0.5 mile east of 57/60 interchange 0.1 mile west of 57/60 interchange 0.2 mile south of 60 Freeway 0.3 mile north of 60 Freeway 0.2 mile north of 60 Freeway, and 0.2 mile south of railroad tracks 0.4 mile west of 57 Freeway, and 0.6 mile south of 60 Freeway 0.4 mile east of 57/60 interchanges 0.1 mile east of 57 Freeway 0.5 mile south of 60 Freeway 0.1 mile east of 57 Freeway 0.5 mile west of 57 Freeway 0.5 mile east of 57/60 interchange 0.4 mile east of 57/60 interchanges 0.1 mile north of 60 Freeway 0.2 mile south of 57/60 interchange 0.2 mile north of 60 Freeway 0.2 mile south of railroad tracks 0.2 mile east of 57/60 interchanges 0.5 mile west of 57 Freeway 0.1 mile east of railroad tracks 0.1 mile south of 60 Freeway ' Major public facilities within half a mire of a HAZardous MATerial transport route (see Figure II -M-1); does not include private child care centers (as shown in Figure II -F-3. Sensitive Air Receptors and Figure II -G-5, Sensitive Noise Receptors). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT? June S. 1992 __ 8 C o m ceiA m a U Z J i� 0 c C J N. RECREATION AND OPEN SPACE EXISTING SETTING It is the general purpose of the local government to maintain or enhance those physical or other factors that contribute to the "quality of life" for its residents. The quality of life in Diamond Bar is directly related to the type and availability of recreational facilities and open spaces. These two factors are considered integral parts of a well balanced community. Parks provide both active and passive recreational opportunities which enhance the enjoyment of leisure time by its citizenry. In addition, natural or attractive man-made open spaces increase the aesthetic appeal of the area, and help foster a positive community image. a. Regional Parks Regional parks offer more extensive or more specialized recreational facilities than are available at a local level. County facilities also offer attractions that are of county -wide significance and generally not available in local parks; and a spaciousness which the typical small neighborhood park does not provide. Regional parks are of sufficient size to offer facilities for family and group picnicking, camping, nature study, and diversified play areas for all age groups. They can accommodate swimming pools, athletic fields, bowling greens, water -oriented facilities, and golf courses. Regional parks can be further classified as Urban Regional Parks; Natural Regional Parks; and County Wilderness areas. The two largest regional recreational resources in this area are beaches and mountains. The nearby Southern California coast offers hundreds of miles of beaches and ocean activities. Immediately north of the San Gabriel Valley are two other important regional recreational resources; the San Gabriel and San Bernardino mountains. These national forests provide hundreds of miles of hiking trails, dozens of campgrounds, winter ski slopes, and a host of other outdoor recreational opportunities. The Chino Hills State Park occupies several thousand acres along Carbon Canyon Creek in Orange County to the south. Ten years ago, ❑ significant portion of Tonner Canyon was identified as potential acquisition land for this park (EDAW 1982). However, the present boundaries of potential acquisition lands for the Chino Hills Park extend only as far north as the Orange/Los Angeles County line (Kelso -Shelton 1991). Therefore, no portion of Diamond Bar's sphere of influence is within the potential acquisition land of Chino Hills Park. Although there are no regional parks within the Diamond Bar city limits, there are several within ten miles of the City. Just north of the City in San Dimas is the Frank G. Bonelli Regional Park, which also contains Puddingstone Lake. This facility provides a wide variety of recreational activities such as swimming, hiking, and camping. Boat races are held periodically on the lake, and there is even a water theme recreation park ("Raging Waters") adjacent to the park. The Schabarum Regional Park, formerly the Off erbein State Recreation Area, is located west of the City in the community of Rowland Heights. Carbon Canyon Regional Park is directly south of the City in Orange County. The Firestone Boy Scout Ranch occupies a large portion of the sphere of influence south of the City (in Tonner Canyon). These and other regional recreational facilities are delineated in Table II -N-1. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSM IINT1 I..we a 100') Table INS 1 Regional Recreational Facilities Source: Los Angeles County General Plan, 1988. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSM IlNT2 ,__a , Size Hiking( FocW/Location (acres) Picnic Swim Riding Camp Comments formerly Otierbein Schabarum State Rec. area Rowland Heights Frank G. Bonelli golf, athletic fields San Dimas 1,982 Ganesha Pomona 80 • San Dimas Canyon San Dimas 138 ' formerly Marshall Canyon S. Frick La Verne 834 Spadra 170 golf, athletic fields Pomona Carbon Canyon 250 redwood grove private, for Boy Firestone Boy Scout Scout groups only Reservation 3,700 Source: Los Angeles County General Plan, 1988. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSM IlNT2 ,__a , b. Golf Courses In addition, the Los Angeles County Department of Parks and Recreation operates the Diamond Bar Golf Course within the City of Diamond Bar. This 18 -hole golf course is open to the public and occupies 178 acres between Golden Springs Drive and the 57/60 freeways. There are also a number of other golf courses nearby, including the Los Angeles National Golf Course, Industry Hills Golf Course, South Hills Country Club (private), Via Verde (private), Mountain Meadows, and the Western Hills Country Club near Chino Hills (private). C. Park Planning Local parks are generally small neighborhood parks equipped to handle active and passive activities. Typical facilities include sports fields, open play areas, play equipment, landscaped areas, walking and jogging trails, picnic and barbecue facilities, and public restrooms. Development of local parks is becoming increasingly important as the City of Diamond Bar becomes more urbanized. In order to assist local government in developing adequate acreage of parkland, the State passed enabling legislation known as The Quimby Act of 1965. The Quimby Act allows local governments to require dedication of local park acreage, the payment of fees, or a combination thereof, as part of the subdivision process. The Quimby Act recommends 3 acres per thousand residents (population) as a minimum parkland requirement. However, the Act does specify that in certain cases, 5 acres per thousand is appropriate if the local jurisdiction makes certain findings on recreation and open space needs of the community. The National Parks and Recreation Association (NPRA) also recommends 5 acres per thousand population. d. Local Parks The majority of Diamond Bar was developed under the jurisdiction of Los Angeles County. During that time, the acquisition of parkland was based on the County standard of 4 acres per thousand residents (LACDRP 1988). However, actual park acreage within the City is significantly below this figure. The total acres of parkland, including proposed but undeveloped parks, is presently 134.9 acres. Table II -N-2 provides a summary of local parks, including undeveloped parkland. Based on a projected population of 75,000 residents, the City will eventually have only 1.79 acres per thousand residents. This does not include "The Country" park, Little League Park, or Diamond Bar Golf Course. The currently developed parkland (59.4 acres) now represents only 0.98 acres per thousand residents (based on a total population of 60,000). If the population of "The Country" is excluded (approximately 4,500), this figure increases to 1.07 acres. There are presently 10 existing or planned parks and 3 "other" recreational facilities within Diamond Bar. The locations of these facilities are shown in Figure II -N-1 and described as follows: Heritage Park Located adjacent to Castle Rock School at 2900 Brea Canyon Road, this 3.4 acre park is one of the oldest in the City. It contains a youth baseball diamond with lights, and a parking lot with 36 spaces. It also contains a small Community recreation room, a half-size basketball court, picnic facilities (3 tables/3 barbecue braziers), tot lot (children's sand play area with equipment), restrooms, and five drinking fountains. Ronald Reagan Park This park, formerly called Peaceful Hills Park, is located on Pathfinder Road at Peaceful Hills. It occupies 6.0 acres of what was formerly Diamond Bar Hill. It has three (3) lighted tennis courts, one (1) lighted basketball court, a large sand play area for children, picnic facilities (2 sheltered areas, 11 tables, 2 cooking areas, and 6 barbecue braziers), and restrooms. Its parking lot has 33 spaces. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 • Starshine Park This small neighborhood park is located at Peaceful Hills Road and Starshine Road, just northeast of Reagan Park. It occupies 2.0 acres and has a tot lot. • Maple Hill Park This 4 -acre neighborhood park is located at 1309 South Maple Hill Road, across the street from Maple Hill Elementary School. It has three lighted tennis courts, one basketball court, a tot lot, picnic facilities (10 tables/3 barbecue braziers), restrooms, and two drinking fountains. Its parking lot has 35 spaces. • Paul C. Grow Park Located at Quail Summit Drive and High Bluff Drive, this neighborhood park occupies 5.0 acres and contains a tot lot, picnic tables, and barbecue stands. This park was developed adjacent to Quail Summit School through a joint powers agreement between the City and the Walnut Valley School District. It has 10 parking spaces in addition to street parking. • Summit Ridge Park This hilltop park commands panoramic views of northern Diamond Bar, including the undeveloped Tres Hermanos and Upper Sycamore Canyon areas (see Section II -D, Biological Resources). It is located at 1425 Summit Ridge Drive just north of Grand Avenue. If occupies 26.0 acres and has a baseball field, playground, tot lot. Par course (20 stations), picnic facilities (2 sheltered areas, 10 tables, and 5 barbecue braziers), five drinking fountains, and restrooms. Its parking lot has 53 spaces. • Sycamore Canyon Park This is the largest and most natural park in the City, although 50 of its 54 acres are presently undeveloped. It is located between the Diamond Bar Golf Course and Diamond Bar Boulevard. On its developed 4 acres, it contains one baseball diamond, a playground, picnic facilities (9 tables and 2 barbecue braziers), five drinking fountains, and restrooms. Its 62 -space parking lot is located at the "low' end of the canyon, at 22930 Golden Springs Road. There is no vehicular access or parking available at its upper end, from Diamond Bar Boulevard. • Peterson Park Formerly the Sylvan Glen County Park, the City recently completed a renovation of this former County park. It occupies 9 acres at 24142 Sylvan Glen Drive, just north of the 60 Freeway, east of Golden Springs Drive. It has two (unlighted) baseball diamonds, a tot lot, picnic pavilion, 2 barbecue braziers, picnic tables, and restrooms. R has 7 acres of undeveloped hillsides and a parking lot for 48 spaces. There are two park sites owned by the City but not developed as yet: • Larkstone Park Located on Larkstone Drive near South Pointe Middle School, this 2.5 acre site is presently undeveloped but is the subject of ongoing negotiations with the Walnut Valley Unified School District, Apparently, the site was involved in some type of land trade among the County, City, and School District. See Section II -O, Educational Services for additional information. • Pantera Park This 23.0 acre site is across the street from the proposed Pomona School District school site. It is undeveloped at present but has had a preliminary master plan prepared for its development. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT II -N-4 June 8, 1992 There are three other facilities in the City that relate to community recreation: Diamond Bar Golf Course This 18 -hole. 72 -par golf course is located along the west side of Golden Springs Drive east of the 57/60 freeways. It is open to the public and is operated by the Los Angeles County Parks and Recreation Department. The course also has club house facilities available for rent to the public. Diamond Bar Little League Fields This "park" is actually four modestly improved baseball fields owned and maintained by the Diamond Bar Little League Association. The fields are located at the west end of Sunset Crossing, next to railroad tracks in the City of Industry. "The Country' Park This oak and walnut tree dotted canyon occupies 132.7 acres within "The Country", a private gate -guarded community in eastern Diamond Bar. The far western part of the "park" property has an equestrian center with an indoor arena, and a tennis club. e. Local Recreational Programs The operation of local recreational programs is currently in transition. The Walnut Valley Recreation Program now provides supervised activities such as sports, games, crafts, and special events. The program is jointly sponsored by the City of Diamond Bar, the City of Walnut, and the Walnut Valley Unified School District. The District presently administers the program through an agreement with the other agencies. However, the District has indicated it will no longer be managing the program offer this year. The City Recreation Department is planning to take over administration of the programs upon termination of the present agreement. Current programs include supervised after-school recreation at Heritage, Maple Hill, and Sycamore parks, excursions for adults to the Rose Parade, special events such as the Diamond Bar Ranch Festival, improvement courses such as Smoke Stop, arts and crafts for children, classes on dance, computers, and youth and adult sports. The City has indicated it intends to offer as many of the current programs as possible, given limitations of staff and budget (Janie) 1990). In addition, the Walnut Valley Young Men's Christian Association (YMCA) operates a number of cultural and recreational programs for City residents. Their Diamond Bar office is at 22600 Sunset Crossing, across from the Little League fields, and supports a pre-school and day care facility. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMEINT5 June e. 1992 cD z H z w N Lu W V) Q J a r z LU i z O z W K w F- U) u) a LL r a Q a m z O a A I I Q swoaiwH 7 X01101 L ■ ■ ■ ■ D o ■ 2 > .c ° > Q d �unop ssaull� ■ ■ pC e E i 0 ¢ .E g c m ° U � N LL U 9 Avg ■ ■ ■ ■ ■ ■ ■ Z � ° o_ c m y cn y p N O =. e'9 d o r ■ 8 a+ s•!q•iL cD z H z w N Lu W V) Q J a r z LU i z O z W K w F- U) u) a LL r a Q a m z O a I I A swoaiwH X01101 ■ ■ ■ ■ ■ ■ ■ ■ H d �unop ssaull� ■ ■ a+ m N LL U 9 Avg ■ ■ ■ ■ ■ ■ ■ Z � c =. ■ . ■ ■ ■ a+ s•!q•iL — R U ■ ■ pwaAaJ ' o"gVI zv3ldcc ■ V m Cn J P•g4611 - spnoo sluusl co s4no� Ipgiuls■g a p0sll ovwa Iwv°u9 N f9 Po 40Nun - *PtbU M•4KQ9 N v L o °AOM sslo P 1 °P•A ' d ,p N N y S . t7 N PDd�OO saoy a o 0 0 0 o o m `o w {ii ° m 9 U - Y Y T — 0 C7 1 d O ° LL U. ° C ° C O J C J 7 O ° S O q ° G • 4 T O 4 ! J i' m 0 N J L r J a O L 7 y y d a or i O N M a mi m r m °; y o r cD z H z w N Lu W V) Q J a r z LU i z O z W K w F- U) u) a LL r a Q a m z O a 0 2 0 z s m� zb ci 0 v g$ Z W mm mo g LL _ o jos -rs _ m �-- $ �� oa g _ ---i �C) Q m�om o�o myEE„m 0md� W� mo _-0u u �EBmm N a +i e: � Yu =C a- N � m 0 0 0 0 3> m 0 0 d Z ap W g Lij / n }( S p �/ Q ,Q,, J �i ri a �ri o r� o o. o `p tai Q 6 (� Z W X U }c' Lu � 0 2 0 z Open Space/Scenic Resources Approximately 20 miles of the 57 Freeway, from San Dimas to Diamond Bar, is considered a "Scenic Drive" (#19) by the County (LACDRP 1988). There are also a number of undeveloped areas in the City that constitute potential open space resources (see Figure II -N-2). These areas are: • Sandstone Canyon, west of Brea Canyon, north of Pathfinder, including the small spur canyon off to the west that passes south of the Middle School. This includes the steep and wooded hillsides along Brea Canyon Road, just east of the canyon, • The canyons and slopes west of the 57 Freeway, south of Pathfinder Road, as well as those south of Brea Cutoff Road (even though they are not presently within the City), • The hillsides dotted with oak and walnut trees east of the 57 Freeway, north of Pathfinder Road and southwest of the corporate office area, as well as the hillsides behind the corporate office park that still retain natural vegetation, all the way north to Grand Avenue, • The south end of "The Country" development that overlooks Tanner Canyon, • The Upper Sycamore Canyon area between Leyland and Diamond Bar Boulevard, including Steep Creek, Clear Creek, and the areas just west of Summit Ridge Park, • The Tres Hermanos area, especially the several small canyons with walnut trees between Armitos and the 60 Freeway, • The rolling hills west of the 57/60 freeways both north and south of Grand Avenue (even though they are within the City of Industry). g, County Regional Trails The County Recreation and Parks Department has an interconnected network of equestrian and multi -use trails planned in the Diamond Bar area, as well as throughout the San Gabriel Valley. The locations of these trails, as well as potential links to other trails, are shown in Figure II -N-3. Additional discussion on the potential links, are discussed in Section II -N-2, Issues and Opportunities. The major trail sections are described below: Skyline Trail Extension This proposed trail extension covers sixteen (16) miles of equestrian trails, extending from Schabarum (formerly Offerbein) Park through the community of Rowland Heights, to Grand Avenue in the City of Diamond Bar, at the Los Angeles/San Bernardino County line. It is primarily routed along Edison electric transmission Right -of -Ways (ROWS). In the vicinity of Diamond Bar, it utilizes the Chino -La Habra Lines Nos. 1 & 2, which are inactive at this time (see Section II -S, Energy Systems). Through the sphere of influence, the trail is routed along the north slopes of Tanner Canyon, adjacent to "The Country" development (Tentative Tracts 47850, 47851, and 48487). The entire trail, from Rowland Heights to Chino, is unofficially called the Schabarum Trail, after County Supervisor Pete Schabarum. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSM ENT II-N-8 $ � )[§ § Z q 2/ )CL u » \ j Q zoo "{§\ \{ � §\j\§§kk)/§ } \ LLJ % )mow 646 / 2 Lli \ 3 - Skyline Trail Connections The County also plans three spur trails to connect wiih the Skyline Trail Extension. The first spur comes north off of the Skyline Extension, west of Brea Cutoff Road in the Puente Hills. If travels north and enters a small canyon near Fire Station #119, passing south of South Pointe Middle School and entering Sandstone Canyon. The second spur leaves the first spur just west of Pathfinder and Brea Cutoff. It travels east along the ridge and enters the canyons just west of the 57 Freeway, south of Brea Cutoff. The third spur goes south off the Skyline Trail in Tonner Canyon enters Sonome Canyon and is intended to eventually connect with Orange County trails in Chino Hills. h. Bicycle Routes Bicycle routes or trails are generally divided into three main categories (LACDRP 1988): • Class I A bike path or trail separated from the roadway and designed for the exclusive use of bicycles. It may be grade separated from a roadway; non -separated routes are often separated by a space or physical barrier. These paths are usually is usually identified with guide signs and pavement markings. • Class 11 A bike lane on a paved area of roadway for preferential use by bicycles. It is usually located along the edge of the pavement, outside of the travel lanes, or between the parking lane and the first vehicle lane. It is identified by "Bike Lane" or "Bike Route" guide signs, special lane lines, bicycle symbols, or "Bike Only" stencils on the pavement. These lanes must accommodate cross-flow of vehicles at driveways and intersections, as well as pedestrians. • Class /it A shared route on a roadway identified by "Bike Route" guide signs only. There are no special lane markings, and bicycles must share the roadway with vehicles. Special regulations may be enacted to post signs along such facilities, to control vehicular speeds, or to restrict parking. The County plans to have bicycle routes serving the region that will connect with local bicycle trails. The County system proposes bicycle trails to enter Diamond Bar at the eastern end of Grand Avenue, and north into the Tres Hermanos property along Tonner Canyon. Surrounding cities have also planned bicycle routes to connect into Diamond Bar north along Mission Boulevard (City of Pomona), west along Grand Avenue and Brea Canyon Road (the cities of Walnut and Industry), and west along Colima Road (into Rowland Heights). A limited number of Class III bicycle routes already exist within the City. Diamond Bar Boulevard and Golden Springs Drive both have painted lanes for bicycles adjacent to the curb, with no parking restrictions. The route on Diamond Bar Boulevard extends the whole length of the City, while the Golden Springs Drive route extends from Brea Canyon Road to the 60 Freeway. Brea Canyon Road also has a painted route on it from Pathfinder Road to Colima Rood. These three main bicycle routes are designed as a loop system to connect Brea Canyon Road with Colima/Golden Springs. The only major deficiency of this loop is on Pathfinder connecting Brea Canyon Road to Diamond Bar Boulevard. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMIIEN T 10 li ina 8. 1992 _-- O m 0 0 z� O 3 U O O > 7s SZ y u u Q( � 0 L m 0 o O J a E m E, W UQ Yl Jj 'u y Z m "$GEo� d Y W mZ - g Ci y0 AZO = .� C_ u O Z O�,N�"W 0w W °o W° g Q 9� o � U O m 0 0 z� 2. ISSUES AND OPPORTUNMES a. Park Planning The City may wish to establish new parkland requirements compared to the previous standards used by the County. The City presently has slightly more than one acre (1.1) of developed parks per thousand residents. Based on its presently planned parks, the City will have (at most) 2.2 acres of parkland at buildout, which is still below both state Quimby and national park association recommendations (3 and 5 acres, respectively). Private park land may receive park credit if public park criteria are met and the private park serves a community, as in the case of "The Country" park. However, the City should be careful accepting any further private parklands as community resources until it is determined they will serve a community benefit and are reasonable to maintain. b. City-wide Park Deficiencies There appear to be adequate regional recreational opportunities available area residents. To accurately gauge the adequacy of local parks for residents' needs, certain service criteria and standards must first be established. Neighborhood parks are considered those with 5 acres or less, or that do not contain sufficient playfield space for athletic programs. Three City parks meet the criteria for neighborhood parks; Reagan, Maple Hill, and Starshine. In addition, three of the parks with baseball ballfields (Heritage, Summit Ridge, and Sycamore) have only one field, which makes it difficult to carpool, schedule tournaments, or share coaching or other resources. The only two parks that have multiple athletic fields are Paul C. Grow and Peterson, and the Grow fields are part of the adjacent Quail Summit School. City-wide, there will be a significant deficiency of parkland according to appropriate State and national standards. At buildout, with full development of the present facilities planned, the City will have 134.9 acres of parks with 75,000 population, or only 1.8 acres per thousand. If the acreage of the private "Country Park" (132.7 acres) is added, the figure increases to 3.57 acres. If the acreages of the golf course and Little League Park are added to that, the figure increases to 6.76 acres per thousand (506.9 total acres of "parks"). While numerically these figures compare favorably, it may be misleading to count a golf course, private fields, and private park as public recreation land, since they might be developed for non -recreational uses in the future. Using the State Quimby Act guideline of 3 acres, the City needs 225 acres of "actual" parkland to support a population of 75,000 residents. The more stringent National Parks and Recreation Association standard (as well as, the higher Quimby standard) of 5 acres means the City should have 375 acres of parks. This is 240 acres less than the 134.9 acres planned at present. One way to alleviate potential park deficiencies would be to build a community park and/or sports complex somewhere in the City. The only significant concentration of baseball fields is at the Little League Park on Sunset Crossing. However, these fields are in moderately poor condition. They would require significant upgrading and rehabilitation to make them useable as a sports complex. Another location for a possible sports complex would be a portion of the Diamond Bar Golf Course. While this is considered another public recreation (and open space) facility, it serves only a specialized recreational activity (golf), and is not available to children and adults of the general public for more varied recreational programs. There has been some discussion to construct a golf course in the Tres Hermanos area and develop the golf course into a regional shopping center. If this is done, the City should give careful consideration to designating some portion of the site for CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -N-12 community recreation needs. If the City is not able to acquire additional parkland, such as Site "D" from the Walnut Valley School District (see Section II -O, Educational Services), then this would be a near ideal location for such a facility, C. Neighborhood Park Needs It is possible to identify neighborhoods that do not contain sufficient recreational facilities. For the purposes of this analysis, local school fields and playgrounds are counted as they provide additional opportunities for recreation. However, they should not be considered a primary source of recreation. School fields are shared facilities and their scheduling, maintenance, etc., are not under the control of the City. Figure II -N-4 shows a neighborhood level analysis of local parks. Parks less than 5 acres with no athletic ballfields are considered "small" neighborhood parks, which typically serve homes within a half -mile radius. Parks with 1 or more ballfields or that are over 5 acres, but less than 10 acres, may be considered "large" neighborhood parks; these parks also serve homes within a half -mile radius. Parks of about 20 acres or more with athletic facilities are "sub -community" parks, and have service areas of about 1.5 miles, depending on their size. Table II -N-3 shows how the local parks can be classified according to these standards. The service areas for these various parks are shown on Figure II -N-4. In most areas, the location and type of neighborhood schools are also taken into account, as these provide additional recreation space. However, they should not be considered as making up for park deficiencies. Most elementary schools have enough turf area for at least 2 baseball fields, while junior high and middle schools usually have enough for 4 fields. Senior high schools have enough room for 6 ballfields, but are often used to such an extent by school teams that they are unavailable or difficult to schedule for local (City) teams. According to the analysis shown in Figure II -N-4, there are several areas of the City with potential park deficiencies: Brea Canyon Road/Colima Road The older residential areas along Colima around Brea Canyon do not have a neighborhood park nearby; the closest will be Larkstone (when it is completed). This deficiency is partially mitigated by the location of Walnut Elementary School (0.75 mile north on Brea Canyon and west on Lycoming). However, the walking route is somewhat long and through commercial and industrial areas. This should be considered a small deficit unless a "vest pocket" park (a quarter to half acre) could be put in along Colima, within the neighborhoods themselves, or possibly at the end of Rapidview, adjacent to Sandstone Canyon (see Section II -D, Biological Resources). Pathfinder Road/Diamond Bar Boulevard The homes north and southwest of this intersection are not within easy walking distance to a neighborhood park. However, this is partially mitigated by the location of Diamond Bar High School, as well as Evergreen Elementary School. The combination of parks and schools in this area probably provide adequate park facilities, although this might also be considered for a greenbelt or vest pocket park. CITY OF DIAMOND BAR DRAFT M ASTER ENVIRONMENTAL ASSESSMENT' June 8, 1992 II -N-13 Diamond Bar Boulevard/Brea Canyon This area is more rural than other deficit areas of town, and may not need additional park facilities. In addition, Castle Rock Elementary School is within three-quarters of a mile, and provides alternative recreation space. Sunset Crossing This area does not have a neighborhood park, and is only partially within the projected service areas of Summit Ridge or Peterson parks. This deficiency is somewhat mitigated by the location of Armstrong School, which provides field and playground space during after-school hours. The Little League fields are also located in this neighborhood, although their condition and type of use probably preclude much use for general recreation. This neighborhood might be considered for a small park or some miscellaneous recreational facilities built at the Little League fields. Such facilities could be installed in cooperation with Little League, as they would also benefit by providing alternative activities for younger siblings during baseball games. Mission BoulevardlHighland Valley This area is slightly outside the service area of Peterson Park, although residents from this area likely use that facility. One factor that mitigates this potential deficit is the location of Golden Springs Elementary School less than half a mile south of this neighborhood. In addition, various sports and athletic facilities are necessary for an active population to take advantage of recreational programs. Table II -N-4 provides a partial list of some athletic facilities typical of suburban communities. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -N-14 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -N-15 Table Il -N-3 Neighborhood Park Deficiencies Park Acres Fields Park Type Heritage 3.4 1 Small Neighborhood Reagan 6.0 0 Large Neighborhood Maple Hill 4.0 0 Small Neighborhood Storshine 2.0 0 Small Neighborhood Paul C. Grow 1 5.0 2 Large Neighborhood Summit Ridge 2 26.0 1 Community 2 Sycamore 4.0 1 Small Neighborhood Peterson 9.0 2 Large Community Pantera (undeveloped) 23.0 ? Community Larkstone (undeveloped) 2.5 0 Small Community Source: Planning Network, based on National Park and Recreation Association guidelines. 1 Fields and some land belong to Quail Summit School, 2 Actually deficient in field space for community park, CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -N-15 $ } 3 } \ % ` Q /0 Uj 0) C)! 00 ƒ- LU 7 f ] T ) \ k o §« / 3 2 LU k® ' �� L \ } f \ w� - ` Table I -N-4 Recreational Facility Standards Facilities Size Recommended Standard 1 PARKS Community 20-40 acres 1/20,000 Neighborhood 5-10 acres 1/5,000 Mini (Vest-pocket) <1-1 acre 1/1,000 FIELDS3 Soccer/Football standard 1/7,500 Baseball/Softball standard 1/7,500 COURTS Basketball standard 1/2,500 Tennis standard 1/2,500 Volleyball standard 1/5,000 Multi -Use standard 1/7,500 OTHER AREAS Stadium standard 1/50.000 Gymnasium standard 1/20,000 Swimming Pool standard 1/20,000 Community Pool variable 1/50,000 Source: Modified from 'Recreation, Park, and Open Space Standard and Guidelines,• National Recreation and Park Association (1983), and Recreation Elements from the Yorba Linda (1982) and Chino (1985) General Plans. 1 Number of facilities/ population. 2 Park service area radius: community (1 mite): neighborhood (0.5 mile). 3 In communities withouth y sports, every third field should be lighted. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 -- ---- II -N-1 7 d. Open Space/Scenic Resources Much of the available open land within the City is located in steep canyons and along freeways. Some of these areas along the 57 and 60 freeways could be designated as visual open space 'buffer zones" to give a more aesthetic feeling both to travelers and residents adjacent to the freeway. Sycamore Canyon off of Diamond Bar Boulevard has considerable open land in its valley, as well as the steep canyon walls to the east. The slope behind the Gateway Corporate Center lends a natural feeling to the area, softening the visual impacts of development. The City may wish to weigh development constraints in some of these areas against their potential use as open space. The potential open space areas outside of the City limits should be placed in an "Environmental Constraint" zone so that appropriate agencies will coordinate development plans with the City. e. Regional Trails There are a number of potential trail sections the City may wish to tie into the planned County system of trails (see previous Figure II -N-3). The main goal would be to connect the two (now) disjointed spur Skyline Connection Trails off of the main Skyline Extension Trail. It may also be beneficial to create hiking trails along the east side of the Diamond Bar Golf Course that would continue up through Sycamore Canyon Park, and continue on up east into Upper Sycamore Canyon. It may even be possible to utilize the ridgeline or disturbed slope areas to create a trail connecting Sycamore Park with Summit Ridge Park. It may be possible to create a system of trails in the south "Country" area using existing fire breaks and access roads. Access into the Country could be prohibited, with access at the southwestern edge of the "Country", near Hawkwood Road. There may be areas within the City with drainage or other easements that could be utilized for short sections of trail. One example of this would be the easement between the houses just south of Colima Road and west of Lemon Avenue. This easement connects Colima with Sandstone Canyon, at the end of Ropidview. Other areas of the City may be suitable for such multi -use trails. Trails in the sphere of influence should generally follow the planned County system, allowing connections with trails west to the Chino Hills and south into Orange County. Bicycle Routes The City may eventually wish to expand its Class III bicycle trails on the following streets to connect with surrounding proposed systems: Golden Springs Drive north to Temple and Mission, Pathfinder Road from Diamond Bar Boulevard to Brea Canyon Road, and the Tres Hermanos area from Tanner Canyon around 10 Golden Springs Drive There appear 10 be very few locations where Class I (off-street) bicycle lanes are practical due to the width of pavement and right-of-way. However, the City may want to explore these in appropriate locations since they are much safer than on -street lanes. In areas with limited pavement, right-of-way, or high speeds, the City may want to upgrade some of its Class III routes to Class II Bike Lanes. by,protecting them from adjacent traffic with asphalt or concrete dikes. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSE SS June 8, 1992 MENT __ II -N-1 A O. EDUCATIONAL SERVICES EXISTING SETTING The educational needs of Diamond Bar residents are served by a variety of agencies. A variety of public and private day care programs are located in the immediate area. Compulsory education (grades Kindergarten through 12th grade) are provided by two public school districts; Walnut Valley Unified and Pomona Unified. There are at least four institutions of higher learning within 10 miles of the City. The County also operates a community library in Diamond Bar. a. Walnut Unified School District The Walnut Valley Unified School District (WVUSD) serves portions of the cities of Walnut, West Covina, and Industry, as well as the southern portion of Diamond Bar, The District is unified, serving students in grades K through 12. Children living generally south of the power lines north of Grand Avenue in Diamond Bar attend WVUSD schools. The District has a total of 15 schools, with 8 of these located in the City. Diamond Bar students attend 5 elementary schools serving grades K-5, two middle schools serving grades 6-8, and Diamond Bar High School, which houses 9 -12th grade students. The District Office is located adjacent to the Walnut Elementary School on Lemon, north of the 60 Freeway. The location of WVUSD schools is shown in Figure II -0-1, while their facilities are summarized in Table II -0-1. District -wide student enrollment has been increasing during this decade, from 8,764 in 1984-85 to 12,407 at present (1990-91). Enrollment is expected to continue to increase (Chaput 1990). Table II -0-1 indicates that the total number of Diamond Bar students is less than the total capacity of existing facilities. However, it should be noted that almost half (49%) of the classrooms are relocatable (portable), which indicates a severe shortage of permanent classroom capacity. Two schools presently consist of all portable buildings; Quail Summit Elementary and South Pointe Middle. In 1991, local voters approved a multi-million dollar bond sale to fund construction of permanent facilities to replace portable facilities at Quail Summit Elementary and South Point Middle Schools, as well as Westhoff Elementary School (which is not in Diamond Bar). It would also be used for the Phase II expansion of Diamond Bar High, to increase its capacity from 1400 to 2400 students (Chaput 1990). Various program or facility changes may be necessary in the coming years as State monies are increasingly regulated and (often) are simply inadequate for current needs. Last year, as in most past years, the State "ran out" of school construction funds part way through the year. This meant that construction of new schools and rehabilitation of older facilities throughout the State was postponed until this year. Even with the recent passage of State school building bonds, there is, and will continue to be, a tremendous backlog of school projects to be funded all or in part by the State. The simple fact is that there are not enough State monies available to adequately fund local school facilities needs. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -0-1 Table II -0-1 Walnut Valley U.S.D. Facilities Serving Diamond Bar' Grades Current Permanent Ck =ooms Total School Served Enrollment Capacity Total/Port Capacity Castle Rock Elementary 2975 Castle Rock Road K-5 736 449 28/14 883 Evergreen Elementary - 2450 Evergreen. Springs Road K-5 746 542 25/9 821 Maple Hill Elementary 1350 Maple Hill Road K-5 572 662 22/2 724 Quail Summit Elementary 23330 Quail Summit Drive K-5 494 0 15/15 450 Walnut Elementary 841 Glenwick K-5 560 279 19/10 589 Chaparral Middle 1405 Spruce Tree Drive 6-8 1,015 860 41/13 1,254 South Pointe Middle 20671 Larkstone Drive 6-8 852 0 32/32 992 Diamond Bar High 21400 Pathfinder Road 9-12 2,180 1,495 71/21 2,127 TOTAL 7,155 4,287 253/116 7,840 Percent Portable 46% Source: Walnut Valley Unified School District, 1990. 1 Current Enrollment = Average Daily Attendance (A.DA) as of October 11, 1990 Permanent Capacity = A.DA Design Capacity (State figure) Classrooms = Total is permanent plus portable, Port Is portable Total Capacity = (number of portable classrooms x 30 students) + permanent capacity South Point capacity adjusted to 85% of total since 100% portable CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -0-2 The District owns 28+ acres just east of Diamond Bar Boulevard and Brea Canyon Road. This site (called Site "D") was once planned as a school site, but is considered surplus at this time. The District is now studying various financial plans for this site that would generate additional revenues. These funds could then be used for construction needs elsewhere in the District. The site was appraised for $ 3.7 million in 1988. Under the Naylor Act, if the School District officially declares the site surplus, it must first offer it for sale to local recreation agencies at below fair market value (Chaput 1990). The City and District have sponsored several successful joint ventures in recent years. A city park (Paul C. Grow Park) was built adjacent to Quail Summit Elementary School through a Joint Powers Agreement between the City and the District. b. Pomona Unified School District The Pomona Unified School District operates 34 schools that serve the entire City of Pomona and the northern portion of the City of Diamond Bar. There are five PUSD schools within Diamond Bar at present, as shown in Figure II -0-1 and summarized in Table II -0-2. The District has been growing, increasing by 3,689 students (+17%) in the past four years alone. While enrollments in Diamond Bar have grown during this period, the largest percentage of growth has been experienced in the central and Phillips Ranch areas of Pomona. Prior to discussing historical and projected student enrollments, it is important to discuss the method of calculating school capacity, or the number of students that can be housed at a particular school. The state has historically used specific formulae to calculate school capacity based on square feet per student or the number of recognized teaching stations. However, these formulae do not take into account various local or State mandated programs. For the purpose of determining eligibility for State funding of new schools, these uses are not recognized as "legitimate" uses of classroom space. Such uses may include Resource Specialists, Reading Labs, Computer Labs, child care, preschool, adult education, or English as a Second Language (ESL). Using classrooms for these uses, while improving the quality of educational programs, reduces the capacity of the school according to the State. For example, district -wide elementary capacity of all its schools, according to the State, is 16,359 students, while the District calculates its K-6 capacity at 15,507 students; this represents a difference of 852 students. Since the State allocates funds to build new schools based on their capacity calculations, the District is approximately 1.5 elementary schools more "full"than recognized by the State. Hence it would be more difficult for the District to receive an allocation to build a new elementary school since, according to the State, the District has 1.5 elementary schools "extra". It should be noted that the figures presented in the following sections reflect District capacities, not State figures. Historical enrollments reflect the unique neighborhoods that attend each school. Diamond Point Elementary has absorbed the majority of student growth in northern Diamond Bar. Its enrollment increased from 400 in 1985 to 535 in 1987 (+135). Its projected enrollment for 1991-92 is 541. By 1991-92, its projected enrollment will be at 86% of total capacity. It presently has 6 portables (27% of total), which is within State planning guidelines. Since the areas served by Diamond Point are built out, there should be no short-term student housing problem. Golden Springs Elementary is currently in a growth mode. Due to recent residential building in this area, its enrollment has grown steadily, from 472 in 1984 to 547 in 1987. To house continued projected growth, a boundary change was implemented in 1987 with Armstrong Elementary. By 1991-92, Golden Springs should reach an enrollment of 802, while its capacity is only 842. Its projected enrollment will be at 95% of its capacity, and over 50% of its classrooms will be portable. Prior to the boundary change with Golden Springs in 1987, the enrollment at Armstrong Elementary remained fairly stable. It is now operating very near capacity and is projected to receive more potables in the near future. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -O-3 Lorbeer Junior High has grown slowly over the lost five years, from 495 in 1985 to 550 at present. However, it is expected to reach 652 by 1991-92 while its capacity is presently 643. While the enrollment at Ganesha High has remained fairly stable since 1985, it is very near its capacity, and is expected to reach or exceed it by 1991-92. The projected student housing conditions at Armstrong, Golden Springs, Lorbeer, and Ganesha would typically signal a need for changes in student housing to accommodate growth. To anticipate student housing needs, the District is planning two new schools in northern Diamond Bar. The District has already acquired a new K-6 school site on the east side of Pontera, north of Grand Avenue (Elementary #4). Although an application for State construction monies has been made, no additional State funding is expected prior to 1992. The District has committed to building a new high school within the City limits. The District originally identified four potential sites in the general area of Tres Hermanos, but has narrowed the choice. This school would most likely serve high school students from northern Diamond Bar and Phillips Ranch. This new facility will provide a local school for a growing number of Diamond Bar students and free up needed space at Ganesha and Gorey High Schools to accommodate growth in the Pomona area. The District has committed sufficient funds to provide a high school with minimal facilities; however, matching funding from the State needed to provide the full spectrum of high school facilities is still being pursued. Even though the District collects the maximum developer fees allowed by the State, there is not enough money available at present to fund the expansion (new construction) and rehabilitation projects identified by the District. In addition, new laws regulating priority for State school construction funding will, in practice, require districts to implement multi -track year round school schedules in order to receive limited State school construction funds. In 1991, local voters approved a multi-million dollar bond sale to fund construction of new elementary schools, the construction of a new high school, and the improvement and rehabilitation of older existing schools. C. Year Round School Because of the rapid growth of K-12 enrollments throughout the State, and the recurring lack of funds for new construction, the California legislature passed Assembly Bill 1650 on May 22, 1987. This bill established that the first priority for funding of new school construction would go to districts that implemented year round schooling according to State guidelines. Although there are many instructional benefits, most districts implementing year round schooling are doing so to continue receiving State funds for new construction and rehabilitation projects (Gorsham 1990). Assembly BRI 87, which took effect in January of 1991, further restricts the types of year round school programs needed for priority funding, and requires 50 percent local funding to receive first priority. To keep chances high for receiving new construction monies from the State, the Pomona District will be implementing multi -track year round schedules in addition to seeking methods of raising the 50 percent local funding of project costs. The local school districts should be contacted for additional information on specific aspects of multi -track year round programs. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -0-4 Table Y-0-2 Pomona U.S.D. Facilities Serving Diamond Bar' o = Grades Current Projected District Classrooms -!S Served Enrollment Enrollment Capacity Total/Port Armstrong Elementary 22750 Beaverhead Drive K-6 426 447 445 14/6 Diamond Point Elementary 24150 ,Sunset Crossing Road K-6 504 541 628 24/6 Golden Springs Elementary 245 S. Bollena Drive K-6 690 802 842 14/16 Lorbeer Junior High 501 Diamond Bar Boulevard 7-8 550 652 643 19/5 Ganesha High School 3 1151 Ganesha Boulevard 9-12 1,459 1,554 1,554 57/11 TOTAL 3,629 3,996 4,112 128/44 Percent Portable 34,E Source: Pomona Unified School District, 1990. ' Current Enrollment = 1989-90 figures from '90/91 Enrollment Projections, Final Detail,' May 14, 1990. Projected Enrollment = for 1991-92 from '90/91-91/92 Capacity Study,' May 1990. District Capacity - capacity Including District programs (not State figure). Classrooms - Total is permanent plus portable, Port is portable 2 All schools located in Diamond Bar except Ganesha High School (Pomona). 3 Only a portion of students served by Ganesha High School are from Diamond Bar. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -0-5 a z a Q c iP LLJ Z W U 's $gyp JyVj ��'� O LC Q z o �uwo3go ��oc0°� Z � w O = � O � z g O 0 u 2 N d �a3�Nh V h On 61 OPO Nn 7A O YJ o v 0 O ►I d. School Developer Fees With the passage of Assembly Bill 2926 (Stirling) in 1987, local school districts began levying school fees on new development to fund new school construction. At present, both the Walnut Valley and Pomona School Districts collect $1.58 per square foot for residential units and $ 0.26 on commercial, office, and industrial buildings. According to the enacting legislation, these fees are considered the legal maximum compensation that can be required from local builders for school -related impacts of new development. However, these fees were never intended to fully fund construction of new schools, but to provide only the local match for the State program. With the current condition of the State building program, it is doubtful that local school projects, both new construction and rehabilitation, that depend on State funding, will occur in a timely fashion to provide adequate facilities for Diamond Bar students. e. Post Compulsory Education In addition to the local K-12 schools, there are a number of nearby community colleges and universities that can provide educational service to area residents. Mt. San Antonio Community College (Mt. SAC) is located in nearby Walnut, while the California State Polytechnic University at Pomona (Cal Poly Pomona) is just south of the 1-10 Freeway. The California State University at Fullerton (in Orange County) is just 10 mile south on the 57 Freeway. The Claremont College complex is also located nearby, just 10 miles northeast of Diamond Bar in Claremont. The University of California at Los Angeles (UCLA), as well as the private University of Southern California (USC), are both located under 40 miles to the west, in Los Angeles. The University of California at Riverside is 27 miles to the southeast, in the City of Riverside, in Riverside County. These institutions provide a wide range of academic courses and degrees, from an Associate of Arts (A.A.) degree at Mt. San Antonio College, to a doctor of philosophy degree (Ph.D) at the major universities. During the 1980s, there was much discussion about a possible State university in Diamond Bar. A potential site in Tres Hermanos was even identified. Eventually, Ventura was selected as the site of the next California State University. There does not appear to be another such facility (University of California or private university) being considered in this area at this time. f. Library Facilities and Services The Diamond Bar Library, operated by the Los Angeles County Library District, presently provides community educational services to the City. The one story building occupies approximately 10,000 square feet and is located at 1061 South Grand Avenue, library services have expanded over the years to accommodate growth. Prior to 1968, the City was served by a mobile library. In 1968, the City got its first store front library. The present facility was completed in 1977, and has just recently installed an automated circulation system (Library Fact Sheet 1990). The library currently houses slightly over 47,000 books, 225 periodical subscriptions, 2,588 audio recordings, and a variety of printed and other educational media. The staff of 17 includes one manager, two librarians, two assistants, seven aides, and five "pages" (interns). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 11-0-7 The Diamond Bar Library is classified in 'Group C' according to the Los Angeles County Library Activity Index. This index is based on circulation and registered borrowers. Last year's circulation was 213,510 with 17,760 registered borrowers (30% of City population). The library is staffed and equipped according to this index, which also measures subscriptions, reference materials, requests for service, and support activities (Hunt 1990). According to the 1986-87 Library Activity Index for the County, Diamond Bar had the second highest LAI score within Class C, with a circulation of 215,996 (2nd) and a registration of 15,770 (3rd), although it had only the 6th highest reference collection (113,428 volumes). 3 should also be noted that the highest LAI score in Class C was for the nearby San Dimas library. Clearly this end of the San Gabriel Valley makes extensive use of County library facilities. A second measure of library service is to compare building area and total volumes available to current American Library Association (ALA) and California Library Association (CLA) standards. Both the ALA and CLA use 2 books per capita as a general library planning guide. Many counties, including Los Angeles, generally use 1.5 books per capita as a minimum for service. The ALA and CLA also recommend a minimum of 0.55 square feet for library buildings. Table II -0-3 compares the present library facilities and services to City population. According to ALA and CLA standards, the Diamond Bar Library presently has a deficit of both total volumes and building area; this deficit will increase in the future unless volumes and space are added as the population grows. This, coupled with the high usage experienced at this facility by the County's Library Activity Index, indicates that additional library facilities may be necessary to adequately serve the population of Diamond Bar. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -0-8 Table k --O.3 Library Services Library Services Existing (1990) Future (2010) City Population 53,000 65,000 RECOMMENDED PER CAPITA STANDARDS 1 ALA/CLA Standards 2 volumes 106,000 volumes 130,000 volumes 0.55 square feet 29,000 square feet 36,000 square feet County Standards 1.5 volumes 80,000 volumes 98,000 volumes Diamond Bar Library (existing) 47,000 volumes 47,000 volumes 10,000 square feet 10,000 square feet Difference ALA/CLA <59,000> volumes <83,000> volumes <18,000> square feet <26,000> square feet <33,000> volumes <51,000> volumes Source: Rancho Cucamonga General Plan — Master Environmental Assessment It 989) ALA = American Library Association CLA = California Library AssocWon CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -0-9 2. ISSUES AND OPPORTUNMES a. Student Generation Table II -0-4 provides general student generation rates for Diamond Bar based on census data and total school enrollments. These figures should be revised as data is available from the Walnut Valley and Pomona Unified School Districts. It should be noted that these factors vary over time based on a variety of factors. New homes bought by young families with small children typically produce high student generation rates, while older housing with families with older or grown children produce fewer students. As new neighborhoods are built, local student generation begins around 0.2 students per household, then peaks around 0.4 students as the area fills with younger families. As the housing stock matures, rates slowly decline until they reach 0.2 or less. As older neighborhoods are rehabilitated or older families move out, rates may go up again if younger families with children move back into the area. These neighborhood cycles often last 20-30 years, but can be significantly influenced by changes in local factors such as birth rate or economics. Based on City-wide average student generation rates, buildout within the City limits will generate approximately 2,400 additional K-12 students. It should be noted that these generation rates may be significantly low for new homes, which usually have younger families with more children. In addition, the City-wide rates include households with seniors, renters in apartments, and older units which often contain fewer children. For these reasons, these estimates of additional students should be considered the minimum expected. At the present time, these additional students cannot be accommodated at existing school facilities of the Walnut Valley and Pomona School Districts. However, it is unknown if they will be able to be accommodated by the time they actually enroll in and attend school. Both of the local school districts have pending applications to the State School Building Program to construct new or expand existing facilities. The Pomona District has already acquired a new K-6 site next to the Pantera park site (see Figure II -0-1), and they are also planning a new high school in the Tres Hermanos area. The District also notes that if significant expansion occurs in the Tres Hermanos area, an additional elementary and middle school (or expansion) may be necessary. The Pomona District may also have to expand one of its K-6 schools and Lorbeer School if this area is developed with primarily residential uses. The Walnut Valley District is planning to expand Diamond Bar High School, and replace its largely relocatable (portable) schools with permanent facilities. The anticipated number of additional students can probably be housed if all these new schools and planned improvements are completed. If the City wishes to be more involved in providing school facilities, the City may want to work directly with the school districts on an ongoing basis to help assure that adequate school facilities are available when needed for local students. Such local involvement is warranted because of the current State-wide lack of adequate school funding. b. School Funding At present, both local districts are dependent on the State School Building Program for funding of new schools. Over the past 15 years, State monies have never been adequate to fund all of the school construction projects proposed throughout the State. Therefore, it is likely that only the highest priority projects will be constructed. To be as high on the State priority list as possible, local schools will have, to go to multi -track year round schedules and raise 50 percent local funding. Even then, Stote'monies are expected to be slow in funding local projects. The City may wish to work with the Pomona district 10 help expedite acquisition, funding, and construction of its new high school, as well as the new elementary school on Pantera. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -0-10 Table 9-0-4 Projected School Needs' Junior Higty A Existing Student Elementary Middle High Generation Schools Schools Schools Total Current Students 4,728 2,417 3,180 10,325 Students Per Household 0.28 0.14 0.19 0.61 B. Students Based On New Existing Projected Housing (1990) (buildout) City Population 53,000 65,000 Average Household Size 3.49 3.1 (est) Households 17,000 21,000 Difference 4,728 + 4,000 households times student generation rate 2,417 + 2,440 K-12 students (0.61 per household from "A") 3,180 2,911 C. Students Based On Existing Projected Additional Popukltion (1990) (buildout) City Population 53,000 65,000 Increase + 23 percent Number of Students Elementary Schools 4,728 5,815 Junior High/Middle Schools 2,417 2,973 High Schools 3,180 2,911 K-12 Students 10,325 12,700 Difference + 2,375 students Source: Estimates based on data from Urban Decision Systems Inc. and local school districts (1990 1 One elementary school Is K-5 versus K-6 for other elementary schools. It should be noted that some K-5 students at elementary schools in Diamond Bar are from Walnut: this will artificially Inflate their student generation rate. Junior High/Middle School category has overlaps with grades 6-8 -and 1-8. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -O-1 1 Some districts have formed Mello -Roos Community Facilities Districts (CFDs) to provide permanent school facilities to growing populations. However, neither district has a CFD established at this time. Pomona is the only district with any significant vacant land available for school facilities (Tres Hermanos), and will likely wish to establish a CFD as this area develops. CFDs often have two options for fee payment: the District accepts a letter of credit as a security for in -lieu developer fees, which would eventually be paid directly by the residents of new development to the CFD, or; the developer can provide the CFD fee directly to the district. These fees are then usually passed on in whole or in part to the homebuyers in the form of higher priced housing. A recent court ruling (Mira decision) allows cities to play a key role in assisting school district form CFDs to raise funds to install needed school facilities. C. Diamond Bar School District There has been discussion over the years about forming a Diamond Bar Unified School District utilizing the Walnut Valley and Pomona school district facilities within the City. Based on recent annexation and unification efforts in Orange County, it would be extremely difficult, if not impossible, to form such a district. For example, it took almost 20 years for the Yorba Linda Elementary School District to merge with the Placentia Unified School District. This was only accomplished after the Yorba Linda District agreed to keep their high school students at Troy High School, in the Fullerton Joint Union High School District. The key issue in this decades -long debate was, "should the Fullerton District vote If one of its member elementary districts wants to withdraw its students?" The courts held repeatedly that both of the affected districts would have to vote if students were being withdrawn. The controversy was solved only after the Yorba Linda District agreed to leave its students at Troy, to prevent declining enrollment from impacting that high school. Based on this experience, forming a Diamond Bar School District would require a vote in both districts, which would likely fail H it would cause major changes in the student housing plans of the Pomona District. d. Library Services The County of Los Angeles has indicated it is providing adequate service to the City at present, and there are no plans to expand facilities or services (McClintock 1990). It should be noted that most communities find it difficult if not impossible to maintain full American or California Library Association standards for volumes or square feet. However, the City may wish to discuss potential service deficiencies, and recommend appropriate action to the County Library system. To this end, the City may consider forming a community services task force or other civic group to study short- and long-term service needs of Diamond Bar, including library services. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -0-12 P. WATER 1 . EXISTING SETTING a. Water Agencies Diamond Bar is entirely dependent on water imported from outside of Southern California. Water is purchased from various non -local sources by the Metropolitan Water District of Southern California, which in turn supplies 27 smaller wholesale distributors throughout Southern California. The local wholesale water distributor for the Diamond Bar area is the Three Valleys Municipal Water District, while retail water is provided by the Walnut Valley Water District. Metropolitan Water District (MWD) The MWD obtains water from Northern California, through the Sacramento/San Joaquin Delta -State Aqueduct System, and from the Colorado River through the Colorado River Aqueduct (Hansen 1990). However, these historically dependable sources are now threatened by four major factors: • The state is entering a fifth year of drought; • The City of Los Angeles, a major MWD customer, has tripled its annual water demand from 150,000 to 450,000 acre-feet due to a curtailment of wafer from the Owens Valley and Mono Lake; • The State of Arizona will presently complete the Central Arizona Project, a major aqueduct which will reduce MWDs annual entitlement of Colorado River water from 1.2 million to 450,000 acre-feet; and • The ongoing battle between Northern and Southern California over water from the Sacramento Delta. These factors will not only continue to threaten the long-term dependability of water, but will begin severely restricting the availability of water for Southern California (Hansen 1990). Three Valleys Municipal Water District (TVMWD) The TVMWD is one of 27 member water agencies that make up MWD. Water is purchased wholesale from various sources by the MWD, which in turn provides the water wholesale to its member agencies. The TVMWD was formed from the original Pomona Valley Municipal Water District, which was established in January of 1950 to represent its member agencies to the MWD. The TVMWD provides water to 15 local retail water companies or agencies (TVMWD 1990). Member agencies of the TVMWD include the cities of Azusa, Covina, Glendora, La Verne, Pomona, and West Covina, the California State Polytechnic University at Pomona, Mount San Antonio Community College, Boy Scouts of America (Firestone Boy Scout Camp in Tonner Canyon), as well as six municipal or private water companies (including the Walnut Valley Water District). Walnut Valley Water District (WVWD) The WVWD was formed in 1952 according to Section XIII of the State Water Code, and has been serving Diamond Bar since 1976 (Lewis 1990). The WVWD covers approximately 28 square miles and serves portions of the cities of Walnut, West Covina, Industry, Pomona, and the community of Rowland Heights (CPP 1987). The WVWD is an independent water district that can set water use rates, charge consumption and hookup fees, and sell bonds (with voter approval) for construction of new water facilities (CPP 1987). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-1 b. Surface Water Water Supply Almost all (90 percent) of the WVWD's water comes from the Weymouth Water Treatment Plant in La Verne, with the remaining 10 percent supplied by the Miramar Plant. However, water from the Miramar Plant is considered surplus and could be curtailed (Lewis 1990). In 1989-90, the WVWD used 22,700 acre-feet (20.3 million gallons per day of MGD) of imported water from TVMWD, 100 acre-feet (89,300 gallons per day) of local well water (for blending into their reclaimed system), and 1,000 acre-feet (0.9 MGD) of reclaimed water (TVMWD 1990). The WVWD is in the process o1 preparing a new Five Year Plan. The previous Master Plan (1981-90) projected a 1990 total WVWD service population of 86,000 with an ultimate population of only 45,000 for Diamond Bar. The new Master Plan is designed to account for all presently planned population growth. Its implementation will provide for adequate future service (Lewis 1990). The long-range estimate for growth within WVWD boundaries is 105,000 by the year 2000, based on a current population of 86,000 (LACDRP 1988). The City of Diamond Bar is expected to ultimately represent 75,000 (71 percent) of the total service needs of the WVWD. The Tres Hermanos area is outside of the present WVWD boundaries and would need to acquire its own (new) separate water source and delivery system. This could be accomplished by either annexing into the WVWD or making provision for service with the City of Pomona Water District (Hernandez 1990). This area is within the sphere of influence of the WVWD, however, the master plan of the TVMWD indicates a future water treatment plant needs to be located in the Tres Hermanos area (TVMWD 1990). Tonner Canyon is presently within the sphere of influence of the WVWD, but is not within their present service area (Lewis 1990). Delivery Systems The City of Diamond Bar and its sphere of influence contain two regional water supply facilities; the Yorba Linda Feeder and the Orange County Feeder. Wafer is provided to much of the Orange County MWD service area by the MWD Yorba Linda Feeder, which carries raw (untreated) water to the Robert B. Diemer Water Treatment Plant in Brea. This feeder passes under the Tres Hermanos area through Tonner Tunnel #11, through the upper portion of Tonner Canyon, and continues south through the Chino Hills via Tonner Tunnel #2 to the Diemer Plant. There is an additional turnout planned on the Yorba Linda Feeder to serve the Tanner Canyon area, including Chino Hills and Tres Hermanos (Camp Dressler & McKee 1983). Utilizing this pipeline would require anew water treatment plant (as indicated in the TVMWD Master Plan) since the Yorba Linda feeder only carries raw water. The Orange County Feeder runs along Brea Canyon Road through Diamond Bar, carrying treated water from the F.E. Weymouth Water Treatment Plant in La Verne to the Diemer Plant into Orange County. This feeder presently conveys water south from the Weymouth water treatment plant to the Diamond Bar area. The locations of major water facilities in Diamond Bar are shown in Figure II -P-1. Within the WVWD, all available water service from the Weymouth (La Verne) Plant is at maximum capacity during the hottest summer days (Lewis 1990). To provide additional service, the WVWD is constructing a new pipeline called the Badillo-Grand Transmission Main. This pipeline will connect with the MWD Middle Feeder with the WVWD. With this new line, WVWD will have sufficient water supply for full development of the area (Lewis 1990). This pipeline alone will double WVWD's present water supply capacity. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-2 The WVWD maintains a backbone water delivery system of 10 -inch to 21 -inch pipelines in Diamond Bar. These pipes are located within major roads, and deliver domestic (drinking) water through local 4 -inch and 8 -inch distribution mains. Most of the major lines are already constructed, although several links or extensions will be completed as projects are approved in undeveloped areas (Lewis 1990). The Tres Hermanos area will need to have a complete water service system constructed commensurate with development (Lewis 1990). The Firestone Ranch in Tonner Canyon is presently served by a 4 -inch metered line from the Orange County -Feeder. However, the Orange County Feeder is already fully committed, so future service will probably be provided by an additional MWD hookup along the 57 Freeway at Lambert Road in Orange County. The canyon will not support any significant development without new water supply arrangements (letter from Boy Scouts to WVWD dated December 18, 1989). Storage Facilities The Walnut Valley Water District presently has seven reservoirs located within Diamond Bar, with an additional two (2) to be constructed in the Upper Sycamore Canyon area (north of Grand, east of Diamond Bar Boulevard) as development warrants. The location of these reservoirs is shown in Figure II -P-1. The WVWD is planning to eventually double the storage of its reservoirs, from 4 to 14 million gallons per day, which will provide three average days of storage (Lewis 1990). The District also operates thirteen pump stations, six of which supply reservoirs, and provide water with adequate pressure throughout the City (Lewis 1990). The location of these stations are also shown in Figure II -P-1. In addition, the MWD is considering a regional reservoir in middle or upper Tonner Canyon. Such a facility could store 60,000 to 100,000 acre-feet of water. However, this reservoir is not included in the TVMWD 1990 Project Needs Report (Hansen 1990). Water Quality Water provided by the WVWD (from the MWD) is from a combination of sources, primarily from the Colorado Aqueduct, with the balance from the California Aqueduct. Water from the WVWD is fully treated and meets or exceeds all current drinking water quality standards (Lewis 1990). In general, drinking water provided to Diamond Bar by the WVWD is of good quality. Table II -P-1 provides a summary of constituents in the water provided to Diamond Bar, along with appropriate State and federal water quality standards. At present, there are no constituents measured that represent a significant health concern in these sources (Lewis 1990). C. Groundwater Groundwater is not presently utilized for domestic supply by the Walnut Volley Water District. Although it is available as a potential future supply, its quality is not presently adequate for domestic consumption without considerable treatment and dilution (Lewis 1990). Water Quality The present quality of groundwater is poor due to contamination by nitrates from previous farming (dairy) activities, manganese, and high levels of total dissolved solids (TDS). Table II -P-2 shows typical levels of groundwater constituents, based on sampling from a WVWD well located within Diamond Bar (see Figure II -P-1). Because of the high TDS levels, local groundwater must be diluted at a ratio of 17:1 to keep it within acceptable levels for landscape irrigation (see Reclaimed Wastewater later in this section). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT .lune 8, 1992 II -P-3 O O 0 Z N C w LU Ugwo �z7 11J n Bio LL e o � L'����EMI L O O 0 Z Table "-1 WVWD Water 9uality t Health Weymouth Miramar Standard Constituent Standard 2 PIoM Plant PRIMARY Coliform Bacteria (%) 10 MND MND STANDARDS MND MND Turbidity 0.5 MND MND Organic Chemicals Atrazine 0.003 MND MND Bentazon 0.018 MND MND Benzene 0.001 MND MND Carbofuran 0.018* MND MND Carbon Tetrachloride 0.0005 MND MND Chlordane 0.0001 * MND MND 2,4-D 0.1 MND MND Dibromochloropropane 0.0002 MND MND para -dichlorobenzene 0.005 MND MND 1, 1 -Dichloroethane 0.005* MND MND 1,2-Dichloroethane 0.0005 MND MND 1,1-Dichloroethylene 0.006 MND MND cis-1,2-Dichloroethylene 0.006* MND MND trans-1,2-Dichloroethylene 0.01 * MND MND 1,2-Dichloropropane 0.005* MND MND 1,3-Dichloropropene 0.0005 MND MND Di (2-ethylhexyl) Phthalate 0.004* NA NA Endrine 0.0002 MND MND Ethylbenzene 0.68 MND MND Ethylene Dibromide 0.00002 MND MND Glyphosate ("Roundup's 0.7* NA NA Heptachlor 0.00001 * MND MND Heptachlor Epoxide 0.00001 * MND MND Lindane 0.004 MND MND Methoxychlor 0.1 MND MND Molinate 0.02 MND MND Monochlorobenzene 0.03 MND MND Simazine 0.01 MND MND 1,1,2,2 -Tetrachloroethane 0.001 MND MND CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-5 Table II -P-1 WVWD Water Quality' Health Weymouth Miramar Standard Constituent Standard 2 PIaM Plant PRIMARY Tetrachloroethylene 0.005 MND MND STANDARDS (Continued) Thiobencarb 0.07 MND MND Triholomethanes (total) 0.1 0.05 0.051 Toxaphene 0.005 MND MND 2,4,5 -TP (Silvex) 0.01 MND MND 1,1,1 -Trichloroethane 0.2 MND MND 1,1,2 -Trichloroethane 0.032 MND MND Trichloroethylene 0.005 MND MND Trichlorofluoromethane (Freon 11) 0.15* MND MND Trichloro-trifluoroethane 1.2* NA NA (Freon 113) Vinyl Chloride 0.0005 MND MND Xylenes 1.75 MND MND Inorganic Chemicals Aluminum 1.0 0.13 0.5 Arsenic 0.05 0.002 0.002 Barium 1.0 0.081 0.042 Cadmium 0.01 MND MND Chromium 0.05 MND MND Fluoride 3 1.4 0.2 0.08 Lead 0.05 MND MND Mercury 0.002 MND MND Nitrate (as Nitrogen) 10.0 0.26 0.51 Selenium 0.01 0.001 MND Silver 0.05 MND MND Radioactivity 2 Gross Alpha Activity 15.0 0.3 2.4 Gross Beta Activity 50.0 4.9 2.1 Radium 226 5.0 0.1 MND Radium 228 5.0 MND MND Strontium -90 8.0 MND MND Tritium 20,000 MND MND CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-6 Table 1{-P-1 WVWD Water Quality 1 Health Standard Constituent Standard Weymouth Plant Miramar Plant Uranium 20.0 2.0 1.0 SECONDARY Chloride 500.0 77.0 96.0 STANDARDS NS 239 110 Color 15.0 <5 <5 Copper 1.0 MND MND Foaming Agents (MBAs) 0.5 MND MND Iron 0.3 MND MND Manganese 0.05 MND MND Odor 4 3.0 MND MND Sulfate 500.0 182.0 39.0 Total Dissolved Solids (TDS) 1,000.0 504.0 305.0 Zinc 5.0 MND MND ADDITIONAL Asbestos NS MND MND CONSTITUENTS Calcium NS 57.0 21.0 Hardness (CaCO3) NS 239 110 Magnesium NS 23.5 14.5 pH 5 NS 8.15 8.2 Potassium NS 3.9 3.5 Sodium NS 77 65 Source: '1989 Water Quality Report,* Walnut Valley Water District. 1990 1 90 percent of Diamond Bar water supply comes from Weymouth Water Treatment Plant, 2 Maximum Contaminant Level (MCL) given in milligrams per liter (mg/I) which is equivalent to parts per million (ppm), except radioactivity, which is given in pica curies per liter. r) means a propose standard that has not yet been adopted. NS = No Standard. MND = Measured but Not Detected. 3 maximum allowed - actual standard varies depending on temperature from 1.4 to 2.4 mg/I. 4 MND for odors means no odors detected above threshold levels. 5 measures acidity (pH <7) and alkalinity (pH >7). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-7 Manganese has been measured at levels of up to 30 mg/I in local wells, compared to the State standard of 50 mg/I. Even though these levels do not now exceed standards, they are of concern as their concentrations have been increasing in recent years. The Puente Basin, which provides local groundwater, is presently adjudicated among its various service agencies. The Puente Basin Water Master is charged with monitoring water use as well as water quality within the Puente groundwater basin. Although the Walnut Valley Water District does not use local groundwater for drinking, it does blend groundwater into its reclaimed water system. Planned Improvements The MWD is planning a $4 billion capital expansion program that will have benefits and impacts on all of Southern California. This program is necessary to meet new water quality and treatment regulations. While the MWD is exploring possible financing options, it is most - likely the costs of this program will be borne primarily by consumers through higher water rates and assessments on property owners (Hansen 1990). The TVMWD is developing Benefit Zones so local agencies can authorize projects within their service areas and finance them through local assessments. The TVMWD is also working with its member agencies to develop wafer reclamation programs and secure financial assistance from MWD through its Local Projects Program (Hansen 1990). d. Reclaimed Water The WVWD presently provides its service area with an extensive reclaimed wastewater system. In 1985, Southern California faced a potential loss of over half of its Colorado River Water upon completion of an Arizona Aqueduct project. The WVWD responded by constructing a reclaimed wastewater system in 1986. Although this system does involve wastewater, it will be discussed in this section because it is an additional source of water that can "free up" potable water for domestic consumption (Hansen 1990). Reclaimed water is now supplied to the WVWD from the Pomona Valley Treatment Plant, operated by the Los Angeles County Sanitation District. This plant is now at (treatment) capacity, but is being expanded from 10 to 15 MGD. However, most of this increase is expected to go to other water agencies. The WVWD is not presently receiving its contractual allotment of reclaimed water due to an over commitment of the present supply (Lewis 1990). The reclaimed water distribution system is shared with the Rowland Water District. Major reclaimed water lines in the City are located within Colima Road/Golden Springs Drive (west of Grand Avenue), in Grand Avenue (and its planned extension) north to Valley Boulevard, and the Gateway Corporate Center streets. Reclaimed water is pumped to and stored locally in the Ookleaf Canyon Reservoir, located on Brea Canyon Cut-off Road just north of Pathfinder Road. The major components of the reclaimed wastewater distribution system are shown in Figure II -P-2. This system now provides water to a variety of public uses. The water meets the State health standards for non -contact uses such as landscape and turf irrigation. Major local users include the playfields at Walnut Elementary School, the Diamond Bar Golf Course, and a number of landscaped medians along Grand Avenue, Valley Boulevard, Colima Road, and the 57 and 60 freeways. These uses presently consume an average of 0.36 MGD with a peak use of 1 MGD (Yoshida 1990). Reclaimed water is blended with local groundwater to meet peak demands. The WVWD presently uses groundwater from one of its wells (2S/l OW -13A2) to augment water for the reclaimed system. Raw (unblended) reclaimed water must be diluted at a ratio of 17:1 to meet acceptable standards of total dissolved solids for landscape irrigation. Reclaimed water is presently provided to local users at a cost of $315 per acre-foot (Lewis 1990). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-9 Table I -P-2 Groundwater Quality Constituent State Standard (mgM Local WON 2 pH 3 NS 7.9 Nitrate (as Nitrogen) 10 9.1 Total Hardness NS 780 Calcium NS 221 Magnesium NS 55.3 Sodium NS 64 Potassium NS 3.4 Chloride 500 103 Sulfate 500 362 Fluoride 4 1.4 0.5 Boron NS 170 Iron 300 200 Manganese 50 <10 Total Dissolved Solids (TDS) 1,000 1,135 Phosphates NS <0.1 Source: Puente Basin Waterrnaster, 1990. 1 standards given In milligrams per lifer (mgll). 2 U County Department or Public Works Well 2S/9W-181`2 in Diamond Bar. 3 measures acidity (pH <7) and alkalinity (pH >7). 4 maximum allowed - standard varies with temperature (1.4-2.4 mg11). CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-9 ) ) 7 �kCL _LU\ l/}` � �a� 2A$]] a f ■ }`^ LLJQ UJ) $Z! §)/£ƒ/20� 7 LU LLJ ] \ /� — `'— /// 2 / a� ! ) ) e. Water Consumption The Walnut Valley Water District presently estimates that residents in the Diamond Bar area consume an average of 170 gallons per person per day with a maximum (summer) usage of 240 gallons per person per day (Hernandez 1990). Table II -P-3 estimates existing and future water use within Diamond Bar. The City presently consumes approximately 10.0 million gallons per day (MGD) of water, and it is estimated that the City will consume 12.7 MGD at buildout (refer to General Plan Section N, Water, Table IV -P-1). These estimates are based on the existing and projected City populations times a daily consumption rate of 170 gallons per person. Under present overall water supply conditions, this amount of water can be provided now and in the future (Lewis 1990). However, California is entering the fifth year of a State-wide drought, and it will take many years of above-average rainfall (and mountain snow pack) to recharge the existing depleted storage units throughout the State. Within the sphere of influence, two golf courses have been proposed by the Southern California Golf Association on land leased from the Los Angeles Area Council of the Boy Scouts of America. If constructed, these courses would consume considerable amounts of water. Water Conservation Due to the ongoing State-wide drought, the MWD's current conservation goal is 31 percent, which impacts the domestic supply with a 20 percent conservation goal. If an agency fails to meet its conservation goal, they are charged $624 for each acre-foot over their allotment (Hansen 1990). The engineering firm of Brown and Caldwell is presently preparing a Water Conservation Report for the Walnut Volley Water District. Additional new systems will be required to "pay as you go" by showing that their use will not deplete supplies of existing users. The District performs a water audit every three years and subsequently implements a leak detection program if a significant amount of water cannot be accounted for. A leak detection survey was performed on a portion of the City's water mains in 1985. The 1988 water audit indicated that it would not be cost-effective to perform a leak detection survey, since less than five percent of the water loss was due to leakage. This amount is generally considered "acceptable" in terms of water service planning (Lewis 1990). The Walnut Volley Water District is planning future educational programs on water conservation involving local elementary and secondary schools (Lewis 1990). The Walnut Valley Water District is presently doing a rate study to identify upcoming costs and revenues. Over the next five years, water rates are expected to increase at least 25 percent, mainly due to treatment cost increases (Lewis 1990). At present, the District is not planning to implement any specific water conservation rate schedules, such as lifeline rates, surcharges for higher use, etc. However, the Metropolitan Water District just recently announced that it was reducing water supplies by ten percent in an effort to accommodate the drought. The MWD will be adding a 200 percent surcharge on water use over specified amounts to encourage conservation of imported water. R is unknown at present how this will specifically affect water supply, but it is reasonable to assume that water use will need to be closely monitored and controlled in the future as this scarce resource becomes more expensive. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -P-11 2. ISSUES AND OPPORTUNMES The City's present and future water supply depends on regional resources and constraints. The long-term availability of water is a State-wide issue that has not been adequately resolved as yet, especially in light of the ongoing drought. Short-term supplies of water are available to serve additional development in Southern California, and within the City. However, significant cutbacks by water wholesalers, such as the Metropolitan Water District, will affect local short- as well as long-term supplies and costs. At present, it does not appear that MWD will have an adequate and dependable supply of water to continue supporting growth in Southern California, or possibly even to support existing development. The ultimate answer to this question depends on how much water is eventually available and how well water use con be controlled. Present Water Supplies Although the City may wish to augment its present water supply by various means, if will continue to be completely dependent on imported water. The TVMWD and WVWD presently have adequate supplies of water. However, supplies may be rationed and/or water rates drastically increased in the very near future to reduce demand. Reclaimed Water The WVWD now uses reclaimed water for non -contact and irrigation uses. Expanded use of reclaimed water would "free up" more potable water for domestic use. Although reclaimed water has historically been more expensive than either groundwater or imported water, the increasing scarcity of imported water may increase its price so that reclaimed water becomes more cost effective. Reclaimed wafer will most likely be a source of "additional" water as the WVWD expands its reclaimed water service. However, supplies of this water may continue to be limited even with the expansion of the Pomona Treatment Plant (Lewis 1990). Reclaimed water will continue to require makeup water to meet the demands placed on the system, and will be provided within City limits via WVWD's present and future facilities. At present, makeup water is limited to either local groundwater or potable water. The poor quality of local groundwater (in terms of total dissolved solids, nitrates, and manganese) could eventually limit its use for blending with reclaimed water. Likewise, more regional use of groundwater from the Puente Basin could also limit the amount of groundwater available for blending with reclaimed water by the WVWD. If there is an insufficient quantity of groundwater available for blending, the City may not be able to fully utilize the amount of reclaimed water available to it. This could force the WVWD to use more imported water to serve growth or blend with reclaimed water. Thus the City could eventually become even more dependent on imported water. Boyle Engineering Corporation recently prepared a "Water Reuse Feasibility Study" for the City (BEC 1990). The report identified 50 sites covering 3,400 acres that could use almost 3 million gallons of reclaimed water per day; these sites were in addition to those already utilizing reclaimed water. The report concluded that it was feasible (but costly) for the City to pursue a supplemental supply from the San Jose Creek Water Reclamation Plant, which is operated by the Los Angeles County Sanitation Districts. This plant is now being expanded from 65 MGD to 100 MGD, so additional reclaimed water will be available in the future. The report further recommended that new pumping, storage, and transmission facilities be constructed through the City of Industry to Diamond Bar. Total project costs for the complete system would be roughly $17 million, with a first phase cost of just under $10 million. The report identified low interest loans, the Metropolitan Water District - Southern California Local Projects Program, revenue bonds, or certificates of participation as potential .funding mechanisms (BEC 1990). The WVWD is presently working with the City of Industry to obtain additional reclaimed water so the present reclaimed system can be further expanded into Diamond Bar (Lewis 1990). If local water agencies wish to make more use of local groundwater, it will require additional treatment or blending with potable supplies to meet health standards. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8. 1992 II -P-12 Future Sources Additional sources of water could come from other (outside) serving agencies that supply the Three Valleys Water District, or the Metropolitan Water District. Possible water marketing or water transfers from groundwater "rich" agencies in Central or Northern California may be possible through expanded and shared facilities and coordinated operation agreements (Hansen 1990). However, the overall supply of water to the Southern California region is limited, and it is doubtful at this point if totally new sources can be developed to increase the overall supply. Within the City's sphere of influence, the Firestone Boy Scout Camp may be able to utilize "raw" water for irrigation of the proposed golf courses. This could free up potable water that might otherwise have to be used. Water Conservation One way to "increase" local water supplies is to reduce individual consumption, as' long as the original supply is not reduced as local use drops. These types of programs can save significant amounts of water. In six months, the City of Los Angeles reduced their overall consumption of water by 12 percent, and some cities (such as San Juan Capistrano) have achieved 20-30 percent savings. However, emphasis on these programs requires appropriate public relations campaigns to convince consumers that conservation is necessary and beneficial, both to them and the City. They are also less certain than new water facilities that can provide water "guaranteed", as opposed to reliance on the consuming habits of its residents. Based on the ongoing water "crisis", the City may wish to seriously consider various water conservation programs. These programs could be more passive, by simply encouraging residents and employers to conserve, or could be more active, by either offering incentives or by requiring compliance through a variety of enforcement mechanisms. For example, the "Drought Busters" in the City of Los Angeles are essentially code enforcement officers that can issue citations for wasting water. Water conservation programs can include but are not limited to: • Installation of water conserving devices such as low -flow or ultra low -flow toilets and shower fixtures, or "instant" hot water heaters. Such devices can be installed during new construction or retrofitted into existing facilities, and are especially effective when installed in high use areas such as hotels or public facilities. • Cleaning concrete or asphalt areas such as parking lots, driveways, and sidewalks by sweeping instead of hosing off with water. • Reducing irrigation of turf and planter areas. This could include the installation of drip irrigation, automatic timers or other control devices, decreasing the watering cycle, using mulch to reduce evaporation, etc. • Installing xeriscape (drought -tolerant) landscape materials to reduce landscape watering requirements. • Educational programs in local schools to encourage water conservation. City Program On February 1, 1991, the Walnut Valley Water District implemented the following water measures to reduce overall consumption by 15 percent: There shall be no hose washing of sidewalks, walkways, buildings, walls, patios, driveways, parking areas or other paved surfaces, or walls, except to eliminate conditions dangerous to public health or safety or when required as surface preparation for the application of architectural coating or painting. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-13 • Washing of motor vehicles, trailers, boats and other types of equipment shall be done only with a hand-held bucket or a hose equipped with a positive shutoff nozzle for quick rinses, except that washing may be done with reclaimed wastewater or by a commercial car wash using recycled water. • No water shall be used to clean, fill or maintain levels in decorative fountains, ponds, lakes or other similar aesthetic structures unless such water is part of a recycling system. • No restaurant, hotel, cafe, cafeteria or other public place where food is sold, served or offered for sale, shall serve drinking water to any customer unless expressly requested and shall display a notice to that effect. • Al water users shall promptly repair all leaks from indoor and outdoor plumbing fixtures. • No lawn, landscape or other turf area shall be watered more often than every other day nor during the hours between 10:00 a.m. and 4:00 p.m. • No water users shall cause or allow the water to run off landscape areas into adjoining streets, sidewalks or other paved areas due to incorrectly directed or maintained sprinklers or excessive wafering. • The owner and manager of every hotel, motel, inn, guest house, bed and breakfast facility and short-term commercial lodging shall post a notice of such shortage and any necessary compliance measures. • Commercial nurseries, golf courses, parks, school yards, irrigated traffic medians and other public open space, and landscaped areas shall be prohibited from watering lawn, landscaping and other turf areas more often than every third day and between the hours of 6:00 a.m. and 6:00 p.m., except that there shall be no restriction on watering utilizing reclaimed water. • The use of water from fire hydrants shall be limited to fire fighting and related activities and other uses of water for municipal; purposes shall be limited to activities necessary to maintain the public health, safety and welfare. The District has indicated that failure to reduce water consumption by this amount, or failure to adhere to these measures, will result in customer penalties, CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -P-14 Q WASTEWATER ExisnNG SETTING a. Serving Agencies Although local sewers are owned by the City, wastewater collection and treatment services for Diamond Bar are provided by the Los Angeles County Sanitation District (LACSD) No. 21. All of the developed portions of the City are served by District 21. There are three undeveloped areas within the City not presently served by the District. The Tres Hermanos area, as well as the southern and southeastern ends of "The Country" development, are undeveloped and do not require sewer service at this time. In addition, the sphere of influence (Tonner Canyon) is also not now within the boundaries of any sewer agency. The local boundaries of LACSD #21 are shown in Figure II -Q-1. Many years ago, the LACSD contacted the Orange County Sanitation District (OCSD) to investigate if some portion of the Diamond Bar area could be served by Orange County. Since Brea Canyon drains south into Orange County, much of this drainage area within the City could potentially be served by the OCSD. At the time, the OCSD indicated it did not have sufficient treatment or collection facilities in the northeast portion of Orange County to adequately serve Diamond Bar. OCSD has established an official policy that flows outside of Orange County will not be accepted (ASL Consultants Inc., 1991). b. Treatment Facilities Municipal sewage flows are presently treated at the Joint Water Pollution Control Plant in the City of Carson. This facility is owned and operated by the Los Angeles County Sanitation District and has a design capacity of 385 million gallons per day (MGD). It presently treats an average of 378 MGD of sewage, and is operating at 98 percent of its capacity (Yoshida 1990). By 1993, some of the sewage from Diamond Bar will also be treated at the San Jose Creek Wastewater Reclamation Plant in Walnut. This plant is presently operating at its design capacity of 65 MGD, but is being expanded to accommodate 100 MGD by the end of 1992. This expansion is being financed with a low interest State loan that will be repaid with new connection fees (Yoshida 1990). C. Collection System Upon incorporation, the City took over ownership of the local sewer system. However, Diamond Bar has a contract with the Los Angeles County Consolidated Sewer Maintenance District to continue maintenance of the sewers. There are also two major LACSD #21 trunk sewers located within the City of Diamond Bar. These major lines collect sewage flows from local sewers and transfer them to the treatment facilities. The first major line is the Diamond Bar Trunk Sewer, located in Lycoming Street and Brea Canyon Road. It ranges in size from 18 to 36 inches in diameter, and has a capacity of 10 to 30 MGD, depending on its size at that point. As of 1988, this line carried approximately 7 MGD, which represents 70 percent of its minimum (10 MGD) capacity. The second major County line is the Fifth Avenue Trunk Sewer, located south of Golden Springs Drive. R ranges from 18 to 21 inches in diameter and has a capacity of 2.6 MGD. Its flow was last measured at 1 MGD in 1988, which represented 38 percent of its capacity. Figure 11-Q-1 shows the location of these trunk lines. Sewage is conveyed from local lines to the two trunk sewers, then .through the LACSD Interceptor to the LACSD treatment facilities. After treatment, wastes are discharged into the ocean from the LACSD Outfall. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -Q-1 3 � � z LUk� § #ƒ%/) 2LL-222§ < °! ; j 2\=\�- 2 ` )\)§ z /-2z. kk 2 ��z@ @ E=§2a ~ Z §§2k 2$Ea2� ƒ} �a 2 �� k \ - ) § \ d. Local Deficiencies The conveyance of sewage flows from Diamond Bar to LACSD treatment facilities involves the use of large pumping (lift) stations because of the distance and gradient (Scanlon 1990). The County Interceptor line is several miles from the City of Industry Treatment Plant, which is its first stop on the way to the Carson Plant. This plant is also uphill from Diamond Bar, which puts back pressure into the local sewer system. The Fountain Springs Pump Station has experienced ruptures on separate occasions. ASL Consultants Inc. was asked to by the Los Angeles County Department of Public Works to make a study and recommendations regarding this deficiency. Based on their evaluation and recommendation, they are preparing the design to solve the problem, and construction should be completed by the summer of 1992. e. Sewage Generation The LACSD No. 21 uses the rates shown in Table II -®-1 to estimate the amount of sewage generated by existing or new development (Yoshida 1990). According to LACSD figures, single family homes generate an average of 260 gallons per day of sewage. Based on 3.5 persons per household, City residents generate 75 gallons per person per day of sewage. By comparison, the Walnut Valley Water District estimates that Individuals consume 170 gallons of water per person per day. Therefore, Diamond Bar residents convert almost half (44 percent) of the water they consume into wastewater, with the remainder going for washing, irrigation, cooking, etc. Based on a compilation of sewage generation rates as provided by the LACSD, the City of Diamond Bar presently produces 5.73 MGD of wastewater daily (Yoshida 1990). Reclaimed Wastewater Domestic wastewater is presently reclaimed locally at the Pomona and San Jose Treatment plants (Yoshida 1990). The City has seven locations or agencies that utilize 360,000 gallons of reclaimed water each day, including three Caltrans medians on the 57 and 60 Freeways, two Walnut Valley School District sites, Zelman Development in the Gateway Corporate Center, and the Diamond Bar Golf Course. A complete discussion of existing and projected use of reclaimed water is provided in Section II -P, Water of this report. The reclaimed wastewater system is shown in Figure II -P-2. g. Service Fees The LACSD 21 presently charges fees for both new construction and ongoing operations (Yoshida 1990). Existing users participate in the District's Service Charge Program to fund system upgrades, annual operations, and ongoing maintenance costs. By comparison, the District's Connection Fee Program charges new users to hook up to the existing sewage system. The funds from this fee program are used for expansion projects to accommodate growth. Both of these fees are based on the specific type of use for each parcel within the residential, commercial, and institutional categories. The rates for these three user categories are based on consumption data and field studies, while industrial rates are based on actual discharge requirements (Yoshida 1990). Annual residential service fees currently range from about $600 for an apartment or condominium to $1000 for a single family detached unit (LACSD 1990). The LACSD collects $12.50 per single residential unit per year, and $2.00 per year is also contributed to the Accumulative Capital Outlay Fund, which is used to correct deficient sewer systems within LACSD. This was used for the upgrade of the Fountain Springs Pump Station. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -Q-3 Table II -Q-1 Sewage Generation Rates Land Use Specific Lim Sewage Rate Per Dwelling Unit Residential Units Single Family 260 Reduced ratel 156 Condominium 156 Duplex 312 Triplex 468 Fourplex 624 Apartments (5+ units) 156 Mobile Homes 156 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -Q-A Per Acre Residential Acres2 R-1 (20 persons) 85 R-2 (20 persons) 85 R-3 (75 persons) 85 R-4 (140 persons) 85 R-5 (140 persons) 85 RS (20 persons) 85 per 1000 square feet of building Commercial Auto Sales/Repair 100 Bowling Alley 150 Car Wash (full service) 3,700 General Merchandises 100 1-101e1/Motel3 125 Kennel 100 Nursery/Greenhouse 25 Restaurant 1,000 Service Station (gasoline) 100 Store 100 Supermarket 150 Shopping Center 325 Theater 125 Wholesale Outlet 100 Offices Financial (Incl. banks) 100 General 200 Professional 300 CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -Q-A Table R -Q- 1 Sewage Generation Rates Lcnd Use SpectBc Was Sewage Rate Industrial Lumber Yard 25 Manufacturing 200 ("dry" uses) 25 Storage 25 Warehouse 25 Source: Los Angeles County Sanitation District No. 21 (Yoshida, 1990). 1 For seniors, small lot developments, or units with water -conserving fixtures. 2 Sewage for land uses R-1, R-2, etc. 9 ( )equals the number of acres times the number of persons per acre (in 3 parenthesis) times the gallons per person. Per room Instead of per thousand square feet. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -9-5 h. Sphere of Influence Tonner Canyon is not now within the service area of any Los Angeles County Sanitation District. If (or when) this area annexes into the City, i1 will most likely be annexed into Los Angeles County Sanitation District No. 21. The golf course development proposed in Tanner Canyon by the Southern California Golf Association is planned to be served by LACSD #21 (P&DS 1989). New development(s) in this area would have to provide appropriate connections to the existing County disposal and treatment system (Scanlon 1990). Depending on the extent of development, additional sewage treatment and/or collection facilities might have to be constructed to support development of this area (Yoshida 1990). It is also possible that this area could be served by the Orange County Sanitation District, although such a proposal has not been discussed with OCSD. 2. ISSUES AND OPPORTUNITIES The City may wish to consider if it wants the Los Angeles County Sanitation District to continue serving all of Diamond Bar. Much of the LACSD conveyance facilities are 'uphill' of the City, and require pumping of wastes to maintain adequate flows. Maintenance costs for "uphill" systems are usually more costly to maintain than downhill systems. For this reason, the City may wish to discuss potential service by the Orange County Sanitation District. One potential drawback of this plan could be local sewage pipeline system changes needed to redirect flows from west to south. Another drawback of such an arrangement could be the City might have less local influence due to the District's location in another county. The City may wish to prepare a cost analysis and feasibility study for service by the OCSD. If the City were to receive some wastewater collection and treatment service from Orange County, it would not be able to utilize reclaimed wastewater due to:the distance and elevation differences. The City would probably continue to utilize reclaimed water from Los Angeles County, most likely from the newly expanded San Jose Plant. Additional issues related to reclaimed wastewater are addressed in Section II -P, Wafer. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -Q-6 R. SOLID WASTE EXISTING SETTING Each day, tons of waste materials are produced by the modern society that supports the City of Diamond Bar. As the population increases, so does the amount of solid wastes produced. The entire Southern California region is presently facing a waste disposal crisis. Existing landfills are nearing their useful lives, and few new sites are available. This impending shortage comes at a time when the volume of wastes continues to increase. a. Waste Generation The residents and employees of Diamond Bar generate approximately 300 tons of solid waste each day. Since the Los Angeles County Solid Waste Plan does not have land use specific waste generation rates, this estimate is based on rates found in the San Bernardino County Solid Waste Management Plan (1989). b. Solid Waste Management The California Integrated Waste Management Act of 1989 (AB 939) identified the responsibility for waste management to occur at the local level. Thus, cities are responsible for managing their solid waste by source reduction, recycling, composting, and environmentally safe disposal in landfills and transformation facilities. In addition, the new Source Reduction and Recycling Element being prepared by the City will address compliance with AB 939. AB 939 superseded the California State Solid Waste and Resource Recovery Act of 1972, which required each county to prepare a comprehensive waste management plan. In 1986, AB 2948 (Tanner) was passed by the State legislature which required counties to prepare a plan that specifically addressed hazardous wastes. The County's Solid Waste Management Plan was designed to work in conjunction with the County's Hazardous Waste Management Plan to provide guidelines and siting criteria for future landfill and waste management support facilities. These plans do not specifically identify future landfill sites. However, the Hazardous Waste Plan does identify "General Areas Potentially Suitable for Off-site Hazardous Waste Management Facilities". Both of the County's Waste Management Plans identified planning and siting criteria for disposal and other types of waste management facilities. There are presently no disposal sites, either for hazardous or non -hazardous wastes, identified within Diamond Bar or its sphere of influence. C. Disposal The Los Angeles County Department of Health currently issues business licenses to those private refuse haulers desiring to collect and dispose trash in the area. In 1986, the County adopted a Solid Waste Management Plan to plan for the handling and eventual disposal of over eighteen million tons of solid waste generated each year in Los Angeles County. However, it is the City's responsibility to conduct long range planning for the collection and disposal of solid waste under AB 939. The County currently operates three of the nineteen landfills in the County, including Puente Hills, and Spadra landfills. The remaining landfills are operated either by cities or private companies. According to the County Sanitation District fact sheets, three County landfills presently accept wastes from the City of Diamond Bar: CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 9, 1992 II -R-1 Puente Hills Landfill Located near the intersection of the 605 and 60 freeways, this landfill handles about 12,000 tons of Class III (non -hazardous, municipal, solid, and inert) wastes each day. Since 1970, this facility has accepted almost 50 million tons of waste. The Puente Hills landfill is due to close in 1993, but plans to expand the site are being prepared. Spadra Landfill This Class III landfill occupies 323 acres just west of the intersection of Temple Avenue and Valley Boulevard In Walnut. It handles 3,000 tons of waste each day, and has received almost 10 million tons of waste since it opened in 1957. It is expected to remain open until at least the year 2000. An 8 megawatt cogeneration unit was recently installed at this facility. The California State Polytechnic University at Pomona (Cal Poly) operates its LANDLAB project on this site, which will plan the long term reuse of this site when it is closed as a landfill. BKK Landfill This was the only landfill in Los Angeles County to accept hazardous (Class 4 wastes, however, this facility currently accepts only Class III wastes. It is located in the Covina hills, and occupies approximately 70 acres at present. However, 4 has the potential to expand up to 130 acres. It handles 12,000 tons per day of waste. Azusa Landfill This Class III landfill occupied a total of 302 acres, has no additional permitted capacity, and ceased operations on February 22, 1991. It handled approximately 6,500 tons per day. A recent article in The Highlander reported that the County will continue expanding the Spadra and Puente Hills landfills as long as there is available space (November 28, 1990). The article also indicated that the BKK landfill is scheduled to close in 1995. However, there are ongoing concerns about groundwater contamination by leachates (pollutants) from these landfills. The County is preparing the Countywide Integrated Waste Management Plan during 1992. The new plan is designed to address pending landfill closures and provide for adequate disposal space through the year 2010. The City of Diamond Bar must utilize an integrated approach to solid waste management within its jurisdiction including source reduction, recycling, composting, and resource recovery options and planned disposal programs. The Los Angeles County General Plan identifies policies and objectives for meeting solid waste goals until the new Solid Waste Plan can be implemented. d. Recycling/Resource Recovery One major way that the need for new landfills can be postponed is to reduce the amount of materials that must be disposed. In addition to the County's management role, cities have been given the responsibility to reduce their own waste streams. The Beverage Container Recycling Act of 1987 requires cities to establish specific container recycling stations. Cities also have the option of implementing curb -side collection, buy-back, or drop-off centers as collection points for the recycling program. The Integrated Waste Management Act of 1989 (AB 939) requires cities and counties to recycle 25 percent of their wastes by 1995 and 50 percent by 2000. To meet these requirements, the City has recently hired a consultant to prepare a "Source Reduction and Recycling Element" as part of the General Plan. The element will address such issues as curbside recycling and composting, although no programs have been initiated as yet. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 II -R-2 2. ISSUES AND OPPORTUNITIES Local recycling and resource recovery programs could significantly reduce the amount of solid waste generated locally. This in turn could substantially extend the life of local landfills, Curbside collection programs are now being implemented throughout the State, and a number of cities are considering compost collection as well. It is possible that aggressive recycling and resource programs, in conjunction with expanding existing facilities, may provide enough physical waste disposal space to meet the waste disposal needs of the Los Angeles area through the end of the century. However, there will still be a lack of landfill space at some point in the next 10-20 years. The major solid waste issues facing the City are; 1) does the City need or want to identify any areas that could support -waste disposal facilities, and 2) to what degree and how does the City wish to pursue a waste management program. a. Disposal The latest revisions to the County's Waste Management Plan makes it clear that individual areas (regions) will be required to accommodate their own waste needs locally, without relying on the previous system of State-wide disposal sites. The East Son Gabriel Valley should consider its own needs and identify potential landfill sites as soon as possible. This is most effectively accomplished as a region -wide effort, including potential expansion or phasing out of existing facilities. The City should discuss if it has any potential waste disposal sites. It is doubtful if any appropriate sites could be found within Diamond Bar. The sphere of influence does contain numerous natural canyons that could be considered appropriate for such uses. However, Tonner Canyon is considered such an ecologically sensitive area (see Section II -D, Biological Resources) that it is not likely such a facility could be located here without significant harm to the native plants and wildlife. The San Gabriel Valley Association of Cities is presently looking into a rail haul plan for local wastes. This is part of a larger County study to consider hauling wastes east to a future landfill site in the California desert. One of the favored sites at present is Eagle Mountain, the now unused iron mine for the former Kaiser Steel Mill. It is likely that such a plan is at least several years away from implementation (Bohlander 1990). b. Waste Management The City will need to fulfill its legal obligations regarding source reduction under the Integrated Waste Management Law. However, the City has various options as to how it will achieve the goals of the law. For example, many cities have implemented curb -side collection of aluminum cans, glass and plastic bottles, and newspaper. The City may want to investigate how it wishes to reduce Us municipal wastes. The City may also want to investigate a composting program utilizing landscape trimmings from homeowners or park maintenance. At present, there are only pilot resource recovery programs at the local landfills, such as scrap metal or automobile tires, although some resources are periodically recovered by private users. The City may wish to encourage a County program for regional resource recovery. Such a program could be funded by cities based on the proportion of wastes they dispose of at County landfills. The amount of waste reduction produced by this program could then be subtracted from the amount of reduction needed by each City under the Integrated Waste Management Law. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -R-3 C. Natural Gas Distribution Diamond Bar is provided with natural gas by the Southern California Gas Company (Gas Company). There are only two regional high pressure (over 60 pounds per square inch or 60 psi) natural gas lines that cross the City. The first is an underground 30 -inch line that comes west out of Tonner Canyon from Chino. It enters 'The Country" development near Lodge Pole Road and crosses Country park. It then proceeds under Diamond Bar Boulevard near Mt. Laurel Way to a pressure station on the west side of the 57 Freeway. From here, it proceeds west and passes out of the City north of the 60 Freeway along the Union Pacific railroad tracks. The second major line is a 24 -inch underground pipeline that runs north from the pressure station on the previously described 30 -inch line (just west of the 57 Freeway). It proceeds north along Brea Canyon Road and exits the City north of Lycoming. This pipeline branches into two 12 -inch lines at Valley Boulevard, with one branch following Valley northeast toward the substations in Pomona. A smaller 8 -inch line comes off the 12 -inch branch to serve the west and of Sunset Crossing Road. The location of these tines is shown In Figure II -S-1, d. Natural Gas Consumption The residents and workers in the City presently consume a 4,008,025 cubic feet of natural gas each day for heating and other uses. Current energy use within the City was estimated as part of the air quality analysis (see Air Quality Appendix in the EIR). e. Petroleum Facilities Local suburban activities consume considerable quantities of petroleum products such as plastics and fuel. A 20 -inch petroleum products pipeline follows the San Jose Creek from the Pomona area into Los Angeles (CDFG 1982). A major earthquake could damage this facility (see Section II -L, Health and Emergency Services). There are no oil extraction, pumping, or refining facilities within the City. There are also many oil wells and pipelines located in Tonner Canyon, although few (if any) are within the City's sphere of influence. Most of these facilities are in the lower portions of the canyon, adjacent to the 57 Freeway. This area is part of the Puente Hills/Brea Production Unit of the Los Angeles County Oil Basin. The geological structure of the area has allowed oil to collect in subsurface formations, which is slowly being extracted by a number of oil companies, including Unocal and Brea Oil Company, among others (see Section II -B, Earth Resources and Seismicity). This area, adjacent to the City's sphere of influence, has already been proposed for major development as oil production is slowly phased out (Unocal -Chapman 1990). Each day, residents and workers in the City consume a substantial quantity of gasoline, diesel fuel, plastics, and other products derived from petroleum. It is not possible to accurately estimate how much of these materials is consumed. However, it is likely that they are consumed in quantities similar to other suburban communities in Southern California. Cogeneration This term generally refers to two different energy processes. The first application is the "cascading" of energy use, typically by substituting natural gas for electricity. In this application, natural gas or some other type of combustive fuel is used to power an electrical generator. The waste heat, which would normally be lost, is recovered and used for some purpose (heating a pool, baking some product, etc.) The electricity is also used to power equipment. While this system requires sophisticated electrical switching equipment and a purchase agreement with the local serving agency, it is a definite way for some organizations, most often large commercial, industrial, or service agencies, to efficiently use energy. At present, there are no major organizations that make use of this type of cogeneration within the City. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -S-2 z OLU o LY Q =t Z N O op U �N O �jZ O N O Nj 6 p Z LLL u Z - CLIJ W g�� Z = The second use of this term is a waste to energy process typically proposed at sanitary landfills. In this application, methane is generated within a landfill by the decomposition of biodegradable materials such as plants, household garbage, etc. This methane, which would normally escape undetected, is collected and burned to produce electricity and sometimes waste heat (similar to the first application). At present, some of the local landfills, such as the one in Puente Hills, utilize this energy process, although it is not a "standard" feature yet at all County facilities (see Section II -R, Solid Waste). 2. ISSUES AND OPPORTUNITIES a. 1 Facilities As the City grows, especially the sphere of influence, additional distribution lines may be required to provide electrical and natural gas service. It is not anticipated that any additional regional 66 kV corridors will be needed through Diamond Bar. However, an additional electrical substation or 66 kV distribution line may be required to serve Tanner Canyon if or when it develops. City planning should take into account the maximum widths of the various electrical and natural gas pipeline easements in the City. The City may also wish to limit land uses along major electrical transmission corridors, as the health effects of exposure to their electrical and magnetic fields is not clearly understood as yet. Open space or lower density activities could be emphasized to limit long-term exposure to residents. However, it should be noted that typical residential and other land uses have already been approved adjacent to these corridors within the City. Safety is also a major consideration when planning land uses adjacent to major natural gas pipelines. b. Consumption The City consumes energy and petroleum products in amounts similar to those found in other suburban communities in Southern California. However, residents may choose to reduce or minimize their consumption of these non-renewable resources. In addition, recent State legislation requires cites to reduce the amount of waste they produce by at least 25 percent by 1995 and 50 percent by the year 2000 (see Section II -R, Solid Waste). Reducing the amount of disposable materials consumed, such as product packaging, yard clippings, etc. will not only reduce the amount of energy (and fossil fuels) needed to produce them, but will also help reduce wastes having to be placed in landfills. The City may wish to investigate solar or alternative energy policies. These should be developed in conjunction with local utility companies and homeowner groups. The City may also wish to sponsor or encourage energy conservation practices throughout the City. Materials on conservation programs is available through Edison and the Gas Company. The City may want to coordinate such programs with local schools. Educational programs on energy conservation can be very effective when taught at an early age, so that behaviors based on wise energy use become part of the decision-making process. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June 8, 1992 II -S-4 C. Cogeneration The City may wish to study, or encourage other agencies to study, the potential for waste to energy cogeneration systems at existing or future landfills. In addition, the City could work with the Southern California Gas Company and the Southern California Edison Company to encourage local businesses to consider substituting natural gas -generated electricity in lieu of purchased electricity. The City could also provide information to large, potential new energy users within the City as to the benefits of using cogeneration. These systems not only help reduce overall energy consumption by using the energy "twice" (once to heat something and the second to generate electricity), but they can be activated specifically during times of heavy usage to reduce peak consumption (arid generation). ,Since the most important criteria is the waste heat requirement, the most effective users of cogeneration usually have a large need for heat, such as a pool or manufacturing process. CITY OF DIAMOND BAR DRAFT MASTER ENVIRONMENTAL ASSESSMENT June B, 1992 ll -S-5