HomeMy WebLinkAbout1995 Diamond Bar General Plan.pdf
GENERAL PLAN
Adopted July 25, 1995
ACKNOWLEDGEMENTS
CITY COUNCIL
Phyllis E. Papen, Mayor Jay C. Kim (Former Councilmember)
Gary H. Werner, Mayor Pro Tem Paul Horcher (Former Councilmember)
Eileen Ansari, Councilmember Don Nardella (Former Councilmember)
Clair W. Harmony, Councilmember John A. Forbing (Former Councilmember)
Dexter MacBride (Former Councilmember)
Terrence L. Belanger, City Manager Gary E. Miller (Former Councilmember)
Robert L. Van Non (Former City Manager)
PLANNING COMMISSION
Bruce Flamenbaum, Chairman Dexter MacBride (Former Commissioner)
Bob Huff, Vice Chairman Grace Lin (Former Commissioner)
David Meyer, Commissioner Lydia Plunk, (Former Commissioner)
Franklin Fong, -Commissioner Clair W. Harmony (Former Commissioner)
Don Schad, Commissioner David Schey (Former Commissioner)
Robert Kane (Former Commissioner)
Jack Grothe (Former Commissioner)
Michael Li (Former Commissioner)
1994 GENERAL PLAN ADVISORY COMMITTEE MEMBERSHIP
Ken Anderson Bernie Mazur
Nick Anis Kathleen McCarthy
Bob Arceo David Meyer
Frank Arciero, Jr. Peter Mitchell
George Barrett Kishor M. Naik
Barbara Beach-Courchesne Steve Nice
Terry Birrell Debbi Noyes
Martha Bruske Arthur O'Daly
Todd Chavers Jim Paul
Haji Dayala Albert Perez, Jr.
Jan Dabney Ray Rebeiro
Ron Fitzgerald Rey Reyes
Edda Gahm Sherry Rogers
Mike Goldenberg Don Schad
Don Gravdahl David Schey
Jack Healy Sue Sisk
Robert Huff Wilbur Smith
Greg Hummel Eric Stone
Jack Istik Reg Truman
Dorian Johnson Steven Tye
Steve Johnson Dan Wildish
Chiman Kotecha Tom Van Winkle
Oscar Law
Joyce Leonard Mayor Gary Werner
Chris Li Councilwoman Eileen Ansari
1990 GENERAL PLAN ADVISORY COMMITTEE MEMBERSHIP
Karla Adams
Carole Anderson
John Bennett
Ross Bilotta
Paul Bordwell
Tim Brunridge
Karen Castleman
Todd Chavers
Noel Cunningham
Jan Dabney
Rose Dam
Bruce Flamenbaum
Art Fritz
Gregory Gaffney
Mike Goldenberg
Clair Harmony
Greg Hummel
Shally Hsu
Bob Kane
Joe Larutta
Ed Layton
Dr. Jui-Kaung Lin
Cartherine Lott
Dexter MacBride
Pat McGinn
David Meyer
Steve Nelson
Khanh Nguyen
Victor Ochoa
Cindee Quan
Don Robertson
Don Schad
Kofi Sefa-Boakye
Mike Sment
Eric Stone
Donald Taylor
Kamal Trivedi
Steve Webb
Ed Yogoobian
CITY STAFF
James DeStefano CoE unity Development Director
Robert L. Searcy, Associate Planner
Ann J. Lungu, Assistant Planner
Marilyn C. Ortiz, Administrative Secretary
CONSULTANTS
Cotton/Beland/Associates, Inc.
Charles Abbott Associates
Diamond Bar General Plan Introduction
July 25, 1995 i
TABLE OF CONTENTS
PAGE
Introduction .....................................................................................................................................1
I. Land Use Element ............................................................................................................I-1
II. Housing Element ............................................................................................................ II-1
III. Resource Management Element .................................................................................. III-1
IV. Public Health and Safety Element ................................................................................IV-1
V. Circulation Element .......................................................................................................V-1
VI. Public Services and Facilities Element .........................................................................VI-1
LIST OF FIGURES
FIGURE PAGE
1 City of Diamond Bar General Plan Community Participation Drawing............................ 6
2 Regional Location............................................................................................................... 7
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INTRODUCTION
Diamond Bar General Plan Introduction
July 25, 1995 1
INTRODUCTION
A. VISION STATEMENT
The General Plan for the City of Diamond Bar has a major role to play in the future of its residents. As
the “foundation for City public policy”, it must be a statement of the hopes and aspirations of its citizens
and should include a shared mental picture or “vision” of our future. This vision of the future is an
important component of the Plan because it serves to communicate the unified intentions of the
community.
The vision must be imaginative since it includes conditions that do not yet exist. But it must also be
practical in order to motivate appropriate action and sustain commitment toward a common direction.
Accordingly, a Vision Statement is useful in the General Plan as a means of defining scope and emphasis
of the Plan. The following Vision Statement is intended to facilitate consensus on overall community
growth and change; and help define key policy issues and resolution strategies.
What are the major components of the Diamond Bar Vision? What do the citizens of Diamond Bar seek
for their community future?
• Retention of the rural/country living community character. There is a strong, long-held
goal among residents to maintain and protect distinctive, physical attributes of Diamond
Bar which make it a desirable place in which to live, through a careful balance of
housing, businesses and services, public facilities, and preservation of significant natural
environmental resources.
• Preservation of open space resources. Significant privately and publicly owned: vacant
areas exist within the boundaries of Diamond Bar and within its Sphere of Influence
(SOI. The preservation of these resources contributes to the goal of retaining the City's
distinctive character and offers educational and recreational opportunities.
Portions of the 3,591 acre Sphere of Influence (SOI) and abutting lands within the City
have been included in Significant Ecological Area 15 by the County of Los Angeles.
SEA 15 is considered to be a major significant ecological asset to the community. The
City will play a proactive role in the preservation of this resource by assuring that
extensive analysis and review precede any changes from its current uses and possibilities.
• Reduction of regional traffic impacts on local streets. Through traffic seriously
encroaches on the City's local streets because of the preexisting inadequate regional
freeway/circulation system. Commuters from neighboring cities make use of City streets
in order to avoid the congested freeway system, to the detriment of local traffic, with
attendant adverse impacts.
Diamond Bar General Plan Introduction
July 25, 1995 2
The City is committed to a proactive involvement in regional efforts to solve and/or
reduce circulation impacts on the local community. Current plans and programs for
implementation of the Circulation Element are designed to reduce congestion.
• Promotion of viable commercial activity. The City will play a proactive role in business
and economic development. Availability of a full range of desired retail goods and
services and production of needed City sales tax revenue will be addressed by an
Economic Resource Strategic Plan.
• Provision of well-maintained, attractive housing which accommodates people of all
ages, cultures, occupations and levels of financial status.
• Creation of a community environment which nurtures social, cultural, religious,
educational and recreational opportunities for its citizens.
The constellation of all parts of this Vision should produce and project an identity which is characterized
by a peaceful, safe community which cherishes the rights of its citizens to grow and prosper, to assemble
and interact constructively, to create and protect family life, and to be represented by an effective, caring
and productive City government.
The Diamond Bar Vision Statement recognizes that a strong, viable partnership between its citizens and
elected officials will be necessary to make the General Plan work toward attainment of the Vision. The
“path” to the future will require a mutual commitment.
“The future is not a probable place we are being taken to, but a preferred place we are
creating. The tracks to it are not found and followed, but made by laying and constructing a
trail” – Peter Ellyard, PhD, 1993.
B. PURPOSE
State planning law requires that each city and county adopt a comprehensive, long-term general plan for
the physical development of any lands in its jurisdiction, and for any land outside its boundaries which
bears relation to its land use planning activities. The General Plan must contain a statement of
development policies, as well as diagrams and text that identify objective, principals, standards, and plan
proposals.
Seven elements are mandated by the Government Code:
• Land use
• Circulation
• Housing
• Open Space
• Conservation
• Safety
• Noise
Diamond Bar General Plan Introduction
July 25, 1995 3
In addition, Section 65303 of the Government Code provides that the plan may include any other
elements which, in the judgment of the legislative body, relate to the physical development of the City.
The combination of two or more mandated elements is permitted. Since many development and
environmental issues are so interrelated, the Diamond Bar General Plan has been organized into five
elements.
Neither the organization or presentation of the elements are placed with implication of priority or order of
importance. Similarly, the listing of goals, objectives, and strategies do not imply priority or magnitude of
importance.
C. REQUIREMENTS
Government Code Section 65300 defines the General Plan as a long-term document. By projecting
conditions and needs into the future, the General Plan establishes a basis for evaluating current policy and
providing insight on future policy. State law requires that general plans be comprehensive, internally
consistent, and long-term.
• Comprehensive - A General Plan must be a comprehensive planning document, covering
not only the geographic area within the City boundaries, but also the areas adjacent to the
City that bear a reasonable relationship to City planning. Areas outside of the City limits
may include the actual Sphere of Influence, as adopted by the Local Agency Formation
Commission, or may be larger or different areas that create planning constraints on the
City. Not only must the General Plan be comprehensive in terms of area, it must also
address all of the relevant issues that legitimately face the jurisdiction (issue
comprehensiveness).
• Internally Consistent - In 1975, the Legislature adopted the “internal consistency”
requirement, which means that all elements of the General Plan are equally important and
must, be consistent with one another. In addition, diagrams within the General Plan must
be consistent with the text. If a new element is adopted or a part of the General Plan is
amended, the rest of the plan must be changed wherever inconsistencies result.
Otherwise, there will be confusion regarding community policies and standards.
In addition to internal consistency, the General Plan must be consistent with zoning a
primary tool in the implementation of the General Plan.
• Long-Term - One of the most important guidelines for General Plans is that they address
a broad enough horizon so that their strategies have sufficient time to be implemented,
and so that their vision is to meet the best long-term needs of the community. However, it
is also important to keep the time frame with reasonable parameters, so the document will
not become dated too quickly, and so that its level of analysis can be more accurate, since
the error rate of projections tends to increase geometrically as time increases.
D. CONSISTENCY WITH OTHER PLANNING PROCESSES
To be an effective guide for future development, the General Plan also must provide a framework for
local development that is consistent with the policies of appropriate Statewide and regional programs and
regulatory agencies. General Plans must comply with all requirements of the California Environmental
Diamond Bar General Plan Introduction
July 25, 1995 4
Quality Act, as amended. In addition, the following legislation or regulations directly affect Diamond
Bar:
STATEWIDE
• Surface Mining and Reclamation Act
• Alquist-Priolo Special Study Zones Act
• Sphere of Influence as regulated by the -Local Agency Formation Commission
REGIONAL - South Coast Air Quality Management District
• South Coast Air Quality Management Plan
REGIONAL - Southern California Association of Governments
• Regional Mobility Plan
• Growth Management Plan
• Regional Housing Needs Assessment
E. COMMUNITY PARTICIPATION
State law requires citizen participation in the planning process. Recognizing the importance of organized
citizen input into the planning process, a 30-person General Plan Advisory Committee (GPAC) was
established in late 1989 by the City Council. The GPAC represented a diversity of groups within the
Diamond Bar community. At the beginning of the General Plan process, numerous interviews were held
with community leaders to provide input to the GPAC regarding citizen concerns. Approximately three
dozen Public Workshops were held with the GPAC on a regular basis through the initial, formulation
stages of the planning process. Quarterly Newsletters were utilized to update the community on the
progress of the General Plan. In April, 1992, the GPAC concluded its activities and transmitted a Draft
General Plan to the Planning Commission for review. The Planning Commission conducted thirteen
public hearings to receive input and consider the 1992 General Plan. Notices of initial public hearings
were provided via letter, full-display ads in local newspapers, and posters and kiosks were displayed
within the community.
In June, 1992, the Planning Commission forwarded the Draft General Plan to the City Council for review
and adoption. The Council conducted six extensively-noticed public hearings and adopted the General
Plan on July 14, 1992. Following adoption of the 1992 General Plan, a residents' group circulated a
referendum petition which was ultimately qualified. The City Council exercised its option to reconsider
the adoption of the 1992 General Plan and as a result, on March 16, 1993, rescinded its prior resolution
which adopted the Plan.
The City Council then directed the preparation of a broad-based community participation program to
encourage and obtain community involvement and create the 1993 General Plan. An extensive series of
five public workshops (April, May) and nine public hearings (May, June, and July) were conducted.
Diamond Bar General Plan Introduction
July 25, 1995 5
Workshops, and public hearings were noticed to the community by means of newspaper ads, posters,
press releases, cable television public service announcements, and direct mailing to approximately 300
persons and organizations. The results of this process were used in formulation of the 1993 General Plan
to accurately reflect the community's consensus of its vision for the future. Subsequent to the adoption of
the 1993 General Plan, a citizens group again presented a referendum petition to the City. The City
Council repealed the 1993 General Plan in December, 1993.
In January, 1994, the City Council assembled the 38 member 1994 GPAC to begin review of the Draft
General Plan. The GPAC was composed of a variety of residents, as well as property owners and
developers with interests within the City, in addition to Mayor Werner and Councilmember Ansari. This
group participated in 14 public meetings and one study session that extended over a six month period.
The GPAC reviewed each element making significant changes, placing greater importance on open space
retention, hillside preservation and improving the quality of life. The results of their deliberations were
forwarded to the Planning Commission for consideration. The Planning Commission conducted numerous
public hearings from July 11 to October 17, 1994. The City Council held public hearings from November,
1994 to May, 1995 to review and consider the General Plan. Figure 1 describes the Community
Participation Program for the 1995 General Plan.
F. CITY HISTORY
The City of Diamond Bar is located in the southeast corner of Los Angeles County, at the intersection of
Los Angeles, Orange, and San Bernardino Counties. The City is situated at the eastern end of the East San
Gabriel Valley, adjacent to both State Routes 57 and 60, as shown in Figure 2. Diamond Bar began as
“Rancho Los Nogales” (Ranch of the Walnut Trees) after a Spanish land grant in 1840. At its height, it
was one of the largest cattle and walnut ranches in Southern California. Until the mid 20th Century, this
land was alternately combined and divided for various agricultural uses. In 1956, the Christiana Oil
Corporation and the Capital Oil Company, a subsidiary of the Transamerica Corporation, purchased the
Diamond Bar Ranch. A comprehensive development plan was prepared and approved for the City,
making it one of the first master-planned communities in the County.
During the 1960's, suburbanization spread eastward from the Los Angeles basin, stimulating local
housing and population growth as Diamond-Bar's open hillsides were replaced by homes. Despite its
initial conception as a master-planned community, Diamond Bar has not developed in an orchestrated
manner. As a result of this development pattern, Diamond Bar today is primarily a residential community.
In March, 1989, local voters voted to incorporate and on April 18, 1989, Diamond Bar became
Los Angeles County's 86th city.
G. MAJOR ISSUES
Planning for Diamond Bar is driven by three overriding issues which have a multitude of implications on
the City's future:
• Land use (including open space)
• Circulation
• The economics of municipal governance
Diamond Bar General Plan Introduction
July 25, 1995 6
Figure 1. City of Diamond Bar General Plan Community Participation Drawing
Diamond Bar General Plan Introduction
July 25, 1995 7
Figure 2 Regional Location
Diamond Bar General Plan Introduction
July 25, 1995 8
While the following sections briefly describe each of these- issues in more detail, it must 'be, remembered
that they are inexorably woven together to form the fabric of the City. The listing of issues is not intended
to imply priorities.
1. Land Use
While much of the City is already developed, there are still substantial vacant parcels of land in the
community and the SOI. Some vacant properties are suitable for development and others should be
preserved for open space because of their significant environmental resource value. Three major sub-
issues affect formulation of land use policy for Diamond Bar. First, economic pressure for development
of vacant land conflicts with the community desire to maintain the quality of the existing environment.
Second, the status of deed and map restrictions affect the development potential of vacant properties.
Resolution of this conflict will require a careful balancing of appropriate development and retention of
open space.
Third, the status of significant environmental resources within SEA 15 (Toner Canyon/Chino Trills
Significant Ecological Area) requires further analysis and definition. As defined by the County of Los
Angeles, it is “a regional, riparian woodland complex”. It is part of a three-county regional environmental
system. The Firestone Boy Scout Reservation, Tonner Canyon Road and cattle grazing have been the only
intrusive uses. However, regional circulation studies have considered various proposals including a
“regional bypass roadway” within the SOI which would help resolve local traffic congestion impacts.
Definition of the precise configuration and alignment of that roadway in order to avoid disruption of
sensitive environmental resources requires further study.
2. Circulation
The City's location at the interchange of major east/west and north/south freeways (State Routes 60 and
57) and pre-incorporation decisions effectively limit the City's ability to achieve an efficient circulation
system. While the local circulation system is adequate for ordinary local traffic requirements, the deficient
freeway interchange forces regional commuter traffic onto local streets creating extreme congestion
during peak travel periods. The multiplicity of relevant county and local jurisdictions and State agencies
both challenges and complicates regional planning solutions. Solutions must include consideration of a
full range of options, including improvement of freeway capacity and access, transportation demand
management and sensitively planned and compatible expanded regional arterial systems. The key to
effective solutions is through continued intergovernmental and inter-agency cooperation.
3. Economics
While Cityhood has brought local control, attendant to that is responsibility for planning for the economic
well being of the City. Short and long term revenue projections are inadequate to support current levels of
municipal services and provision of needed capital improvements. The reasons include limited
opportunities for generation of sales tax; diminishing availability of Federal, State and County funding;
and property tax limitations. Further, the City has an inadequate mix and a limited range of viable retail
uses.
Underlying all proposed responsibilities of government is a fundamental fiscal fact: Virtually all
governmental activity and programs are financed by taxpayer dollars. Whether city, county, regional,
state, or national economic cycles reflect growth and prosperity, or reflect recessive constriction and
depression, the ability of a community and its servant government to pay for services must be a dominant
concern. This General Plan, conceived in a time of regional and state economic recession, recognizes the
Diamond Bar General Plan Introduction
July 25, 1995 9
need for fiscal prudence and effective, efficient management of the community's resources. The General
Plan is also designed to allow for some prudent, careful future expansion when the area's economy has
improved to warrant change. Such recognition embraces a range of imperatives from fiscal survival to
enhancement of Quality of Life.
H. DOCUMENT CONTENTS
The following elements of the Diamond Bar General Plan have been designed to address the variety of
environmental issues that affect the City.
Diamond Bar
General Plan
State Mandated
General Plan Elements Issues
Land Use Element
Land Use
Land Use
Housing Element
Housing
Housing
Resource
Management
Element
Open Space
Conservation
Visual Resources
Biological Resources
Park and Recreation
Water Resources
Energy Resources
Solid Waste
Mineral Resources
Agriculture
Safety
Geology
Seismicity
Flooding
Fire Protection
Crime Protection
Emergency Services
Hazardous Materials
Air Quality
Public Health
and Safety Element
Noise Noise
Public Services and
Facilities Element
City Financing
Economic Development
Circulation Element Circulation
Circulation
Trails
Automobile
Bicycle
Equestrian
Aviation
Truck Routes
Public Transit
Railroad
Diamond Bar General Plan Introduction
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I. GENERAL PLAN FORMAT
The 1995 Diamond Bar Draft General Plan is divided into three documents for ease of reference.
1. Document 1: General Plan
The first document contains the six actual divisions of the General Plan proper, that is, the compilation of
the goals, objectives, and implementation strategies of the Plan. This document contains an Introduction,
and the Land Use, Housing, Resource Management, Public Health and Safety, Public Services and
Facilities, and Circulation Elements.
2. Document 2: Final Environmental Impact Report/Technical Appendices (Certified
7/14/92) (Includes Mitigation Monitoring Plan)
This document contains the Environmental Impact Report (EIR) for the General Plan, including the
Notice of Preparation and Responses. The EIR contains the appropriate environmental documentation for
the General Plan as required by the California Environmental Quality Act (CEQA) including detailed
analyses of the various impacts of ultimate development in Diamond Bar. This document also contains all
of the technical appendices not specifically related to the EIR, such as noise, air quality, land use
summaries and alternatives, etc. An Addendum to the Final Environmental Impact Report (FEIR) was
prepared on the 1993 revised General Plan. Addendum #2 has been prepared addressing the 1995 General
Plan.
3. Document 3: Master Environmental Assessment (adopted 7/14/92)
The Master Environmental Assessment for the City, which provides a comprehensive and consistent
baseline of environmental data from which further (project-specific) environmental analyses can be
performed, was adopted on 7/14/92 and is incorporated by reference as part of the 1995 General Plan.
The organization of the General Plan can thus be visualized as follows:
• Document 1
Introduction
Land Use Element
Housing Element
Resource Management Element
Public Health and Safety Element
Public Services and Facilities Element
Circulation Element
• Document 2
Environmental Impact Report
Technical Appendices
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July 25, 1995 11
• Document 3
Master Environmental Assessment
Diamond Bar General Plan Introduction
July 25, 1995 12
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I. LAND USE
ELEMENT
Diamond Bar General Plan Land Use Element
July 25, 1995 i
TABLE OF CONTENTS
PAGE
A. INTRODUCTION............................................................................................................I-1
B. LEGAL REQUIREMENTS..............................................................................................I-1
C. EXISTING CONDITIONS...............................................................................................I-1
D. COMMUNITY DEVELOPMENT ISSUES.....................................................................I-9
E. LAND USE GOALS, OBJECTIVES, AND STRATEGIES.........................................I-12
F. LAND USE PLAN .........................................................................................................I-27
Diamond Bar General Plan Land Use Element
July 25, 1995 ii
LIST OF FIGURES
FIGURE PAGE
I-1 Existing Land Use.............................................................................................................I-6
I-2 Proposed Land Use Map.................................................................................................I-20
I-3 Possible building Configurations for 0.25:1 Floor Area Ratio.......................................I-29
LIST OF TABLES
TABLE PAGE
I-1 City-Wide Existing Land Uses (1993)..............................................................................I-4
I-2 Sphere of Influence Existing Land uses (1993)................................................................I-5
I-3 General Plan Land Use (By Category) .............................................................................I-7
I-4 Potential Residential and Commercial Growth.................................................................I-8
Diamond Bar General Plan Land Use Element
July 25, 1995 I-1
I. LAND USE ELEMENT
A. INTRODUCTION
It is the desire of the citizens of Diamond Bar to maintain a rural and country living environment.
Planning for the long-range use of land in the City is like fitting together the pieces of a three-dimensional
jigsaw puzzle. Each “piece” of land has unique opportunities and constraints, but may also have many
needs or conditions that are shared by surrounding pieces, such as utilities, fire protection, and protection
from excessive noise. Each piece must be weighed individually, as well as together with surrounding
pieces as an integrated whole. Finally, all pieces must be weighed together to assure that their combined
pattern best fulfills the short and long-term needs of the community. The Land Use Element of the
General Plan provides a framework to unify and organize these “pieces” around several central themes, so
that development of remaining open land will enhance these themes and work toward achievement of the
Diamond Bar Vision.
B. LEGAL REQUIREMENTS
California law requires that each city and county prepare and adopt a comprehensive, long term general
plan for its physical development. Government Code Section 65302(a) requires that local general plans
include a land use element as part of the required general plan. This requirement is intended to ensure that
communities achieve and maintain a logical land use pattern, as well as standards for population density
and development intensity which is consistent with community goals and objectives. Thus, the land use
element has the broadest scope of the general plan elements required by State law.
C. EXISTING CONDITIONS
Diamond Bar is located at the junction of two major Southern California freeways (57 and 60) in the
southeastern corner of Los Angeles County. Although conceived as one of the first planned communities
in the west, it developed mainly as individual and unrelated detached single-family residential tracts, with
a minimal amount of commercial and other non-residential uses.
The City incorporated in 1989, after developing under the jurisdiction of Los Angeles County for-almost
30 years. 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.
1. Residential Uses
Diamond Bar is comprised of rolling hills and valleys between rapidly urbanizing freeway corridors (west
and north) and the largely undisturbed Sphere of Influence (south). According to the California
Department of Finance, the City has a total of 18,196 dwelling units that presently house a population of
59,722 residents (2006). The City is primarily residential. Single family detached units represent the
majority of the City's housing stock. Approximately five percent of the single family units 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 hillside areas (east).
Diamond Bar General Plan Land Use Element
July 25, 1995 I-2
Along the 57 and 60 freeway corridors, single family lots are generally under 10,000 square feet.
Detached single family developments in these areas have been built at 3-5 dwelling units per acre, which
represents over half of the City's entire housing stock. While single family development predominates,
multi-family projects can be found along Diamond Bar Boulevard, south of Grand Avenue and on Golden
Springs Drive, north of Diamond Bar Boulevard. These developments usually occupy small sites along
major roadways, and are built at 10-20 units per acre. The more dense multi-family projects (16 units per
acre) are older condominiums approved by Los Angeles County prior to incorporation. This western half
of the City generally contains the older housing, built in the 1960s and early 70s. The City also has
apartment complexes of moderate density (10.9-16.7 units per acre), with most located on major arterials
such as Diamond Bar Boulevard.
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
density (units/acre) decreases as lot size increases. “The Country Estates”, a private gate-guarded
community, contains 638 homes and occupies 855.5 acres along and just west of the ridge separating the
City from Tonnes Canyon. Here, lots may be several acres or more in size, depending on the severity of
the slope.
2. Non Residential Uses
Non-residential uses comprise about 20 percent of the City's land area. Commercial uses occupy
approximately two percent of the City's land area and are mainly located along Diamond Bar Boulevard
and portions of Golden Springs Drive. 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 84 acres of
industrial/business park uses are located along Brea Canyon Road, north of Lycoming Avenue. Parks,
public facilities, open space, and roads occupy the remaining area.
The building areas shown in Tables I-1 and I-2 are for existing commercial, office, and light industrial
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 support a variety of
commercial, office, and/or business park uses. However, a selective 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.
Other major non-residential land uses include public facilities which encompass schools (158 acres) and
other government facilities; developed and undeveloped parks (470.8 acres); which includes the Diamond
Bar Golf Course (178 acres). At present, there are 2,757.1 acres of vacant land potentially available for
development and/or preservation. Many of these vacant lands are subject to existing map and deed
restrictions which limit their future development potential, and are separately identified in Figure I-1. The
largest parcel of vacant land is the Tres Hermanos property (approximately 800 acres), at the northeast
corner of the City, between Grand Avenue and the Pomona (60) Freeway. Figure I-1 shows the location
of existing land uses within Diamond Bar.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-3
3. Sphere of Influence
The City of Diamond Bar's Sphere of Influence was first approved by the Los Angeles County Local
Agency Formation Commission (LAFCO) on August 8, 1990, and encompasses 3,591 acres immediately
south of the City limits to the Los Angeles County/Orange County border. This sphere area includes the
middle portion of Tonner Canyon - an undeveloped northeast/southwest trending wooded canyon, which
extends beyond the City's Sphere of Influence into Orange County to the south and San Bernardino
County to the east.
Pursuant to the Cortese/Knox Local Agency Reorganization Act, the Sphere of Influence serves as an area
designated as future area to be annexed to the City. However, until such time as the property is annexed to
the City of Diamond Bar the area remains under the jurisdiction of Los Angeles County.
4. Potential Regional Impacts
State law provides that each city and county may include in a proposed general plan any land outside its
boundaries which bears relation to its land use planning activities. Government Code Section 65303
provides that the General Plan may address other subjects which, in the judgment of the legislative body,
relate to the physical development of the city, noting that “no city… is an island in the regional setting”.
Areas of potential impact upon the City of Diamond Bar include proposals for development of a Materials
Recovery Facility near the northwest boundary of Diamond Bar; a proposal to locate potable/non-potable
water facilities; an institute of higher education on the Tres Hermanos Ranch in Chino Hills and Diamond
Bar; potential development surrounding the new City of Industry Metrolink Station (rail facility) adjacent
to the westerly border of Diamond Bar; potential development of vacant land or hills adjacent to the 57
and 60 freeways and the Union Pacific right-of-way in the City of Industry; potential development of
vacant land south of Brea Canyon Cutoff Road and west of 57 freeway and Brea Canyon Road; and
Diamond Ranch High School in Tres Hermanos. These proposals should be carefully monitored by the
City and the City should proactively participate in the planning process where necessary to achieve
General Plan goals.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-4
Table I-1
City-Wide Existing Land Uses (1993)
Diamond Bar General Plan Land Use Element
July 25, 1995 I-5
Table I-2
Sphere of Influence Exsisting Land uses (1993)
Diamond Bar General Plan Land Use Element
July 25, 1995 I-6
I-1 Existing Land Use
Diamond Bar General Plan Land Use Element
July 25, 1995 I-7
Table I-3
General Plan Land Use (By Category)
Land Use Designations
Permitted Density /
Intensity
Gross Acres
In the City
Gross Acres
In Sphere
Total Gross
Acres
Residential Designations
RR Rural Residential
RL Low Density Residential
RLM Low-Medium Residential
RM Medium Density Residential
RMH Medium High Residential
RH High Density Residential
(1 ac/du)
(up to 3 du/ac)
(up to 5 du/ac)
(up to 12 du/ac)
(up to 16 du/ac)
(up to 20 du/ac)
1,392
3,089
838
275
197
66
1,392
3,089
838
275
197
66
Subtotal
5,857
5,857
Non-Residential Designations
C General Commercial
CO Commercial / Office
OP Professional Office
I Light Industrial
(.25 – 1 FAR)
(.25 – 1 FAR)
(.25 – 1 FAR)
(.25 – 1 FAR)
172
63
178
93
172
63
178
93
Subtotal
506
506
Mixed Use Designations
PA Planning Areas
PA-1
PA-2
PA-3
PA-4
(see text)
720
401
55
82
720
401
55
82
Subtotal
1,258
1,258
Other Designations(a)
PF Public Facilities
W Water
F Fire
S School
PK Park
GC Golf Course
OS Open Space
PR Private Recreation
AG Agriculture
Fwy / Major Roads
1 du / 5 ac
27
19
1
345
158
178
642
15
0
684
2
3,589
27
21
1
345
158
178
642
15
3,589
684
Total
9,690
3,591
13,281
(a) No F.A.R. or potential square footage has been identified for these quasi-public and recreational land use categories
due to the wide range of uses permitted (e.g., civic center, schools, etc.) and because buildings are often part of large
open space areas such as golf courses.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-8
Table I-4
Potential Residential and Commercial Growth
Diamond Bar General Plan Land Use Element
July 25, 1995 I-9
D. COMMUNITY DEVELOPMENT ISSUES
The four major land use issues identified in the master Environmental Assessment are: 1) land use mix;
2) capacities of the natural and man-made environment to accommodate growth; 3) City image; and
4) local versus regional needs and short-term versus long-term solutions.
1. Land Use Mix
a. Disposition of Remaining Vacant Lands Including, but Not Limited to, a
Determination of Deed and Map Restriction Status.
Determining the status of remaining vacant lands is a major policy decision facing the City. As part of the
General Plan program, an “Open Land Survey” was conducted to identify possible development
restrictions that might have previously been approved by the County. The survey found that various types
of notations and restrictions had been placed by the County on the subdivision maps creating certain
identified vacant lands. In some cases, deed restrictions were imposed to ensure that development would.
not occur without further legislative review on vacant lands; however, many other notations and
“restrictions” were ambiguous.
ISSUE ANALYSIS: Those lands which have been deed and/or snap restricted should be
pursued as public open space. There is a need for examination of
original and existing deed and map restrictions which affect vacant land
proposed for development. Past confusion resulting from Los Angeles
County transmittal of development entitlements should be resolved.
b. Open Space Definition and Preservation
There are different types of undeveloped lands in the City. These include natural undisturbed hillsides,
ridges and canyon bottoms. Man-made open space can range from graded hillsides that appear “natural,”
to open space areas which have been or may in the future be subject to deed or subdivision map
restrictions which preclude development. Other open space areas include improved properties such as
parks, golf courses, recreational facilities and cemeteries. This General Plan categorizes these different
types of open space areas into distinct and clearly understood designations.
Presently undisturbed hillsides, ridgelines and canyon bottoms located on privately owned property are
susceptible to future development. Therefore, this General Plan sets forth strategies for land use
development that will preserve significant environmentally sensitive areas through the use of techniques
such as transfer of development rights and clustering.
ISSUE ANALYSIS: Open space areas must be given clearly understood and identifiable
designations and preservation strategies must be identified.
c. Economics
The City presently has a modest budget with a small operating reserve. Municipal costs generally tend to
increase faster than revenues, and service needs can be expected to increase faster than services can be
provided. Therefore, the City should control service costs while seeking ways to increase City revenues.
City governments have two basic sources of revenue: Local residents and businesses.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-10
As a means of increasing revenues, the City could attempt to increase property tax revenues by
establishing Diamond Bar as an exclusive community. This might be accomplished by significantly
lowering allowable densities on remaining vacant land and encouraging development of remaining vacant
lands as gate-guarded communities. While resale and new houses in the City command fairly high prices
(slightly over $300,000), market research shows that home prices must exceed half a million dollars
before property tax revenues will qualify the area as an exclusive community. For areas of lower-priced
housing, the City receives a much lower proportion of their revenues from local property taxes. Available
data also indicates that lower priced single family dwellings, condominiums, and other attached multi-
family housing cost proportionately more for services than they generate revenues.
A second source of additional revenue to the City is sales taxes generated by existing or new local
businesses. In general, market research shows that retail commercial uses generate significantly more
municipal revenues as compared to costs. By comparison, business park uses generally “break even,”
while office uses cost more to serve than the revenues they produce for a city.
Potential sources of additional revenues for the City would be new or higher user fees, taxes, or service
assessments. There are a variety of such charges available to cities that can be applied to either residents
and/or businesses.
For these reasons, economic factors are 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. Aside from property taxes and per capita subventions,
sales taxes are often the largest source of municipal revenues. However, the pro rata share of dollars to
municipalities may shift outside of the City's control. It is important for the City to make sound land use
decisions based on the long-term quality of the living environment, rather than solely on the economic
benefits of unpredictable market trends.
Fundamental marketing strategies that cities typically employ, relative to commercial land, to generate
positive municipal revenues/costs are as follows. Cities can choose to attract low-to middle-range
shoppers, or they may decide to focus on upper-or high-end buyers. Depending on location, cities can also
choose between attracting local buyers, or exploiting more regional shoppers. Diamond Bar can target all
of these marketing strategies to maximize its economic return. The City could develop an area with good
freeway visibility and access for high-end specialty commercial and offices uses. These uses could attract
local, as well as a considerable amount of regional shoppers. High-end office uses could also be located
nearby to support these commercial uses. There are also several large shopping centers in the City with
good freeway visibility and access, which can support regional, freeway-serving, or community
commercial uses. Smaller shopping centers located on major streets within the developed portions of
Diamond Bar should be oriented mainly for local use. The City also has the potential to take advantage of
regional mid-range shopping opportunities in the undeveloped northeastern portion of the City, along the
Pomona Freeway.
ISSUE ANALYSIS There is a need to encourage a variety of new or expanded commercial
uses and other non-residential development, as well as investigate other
funding mechanisms, to help finance City services, infrastructures and
amenities.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-11
2. Capabilities Of The Natural And Man Made Environment
a. Natural Resources
Events of this decade have highlighted our limited regional resources, such as air quality, water, and solid
waste disposal. As a new City, Diamond Bar needs to establish its own position on these environmental
issues. Although the City is largely built out, additional growth could place unacceptable limits on
sensitive or scarce resources or on areas subject to hazards such as flooding (refer to flood hazard maps in
MBA).
ISSUE ANALYSIS: There is a need for the City to plan for growth in ways that protect and
conserve natural resources and the environment.
b. Infrastructure Capabilities
At present, the City has a fairly new infrastructure system and operates its services with a slight surplus of
revenues. However, as the City ages, maintenance and service costs go up faster than municipal revenues
increase. The current mix of land uses within the City is insufficient to adequately fund long-range capital
and operating needs.
ISSUE ANALYSIS There is a need to plan now for the anticipated increase in traffic, the
maintenance of existing facilities, fund new facilities, and support future
services to enhance the quality of life in Diamond Bar.
3. City Image
a. Balanced, Residential Community
Although originally intended to be developed as a master-planned community, Diamond Bar has not
developed in an orchestrated manner subject to a master set of covenants, conditions and restrictions. It is,
rather, a more traditional bedroom community, consisting primarily of single-family residential tract
development, punctuated with local commercial businesses and multiple family housing at arterial
intersections. Although the City lacks a “downtown” area which might contribute to a focused image, it
has the reputation of a desirable and attractive place to live, containing many features of a more rural
environment. The vision of the General Plan offers the opportunity to crystallize the image of the
community.
ISSUE ANALYSIS: There is a need to define and promote a City image that reflects the
City's many attributes and its long-term vision.
b. Land Use Compatibility
A major goal of the community is to protect existing neighborhoods and their character. There are outside
pressures on the City to help solve regional traffic problems. At the same time, there are outside pressures
on the City adversely affecting the City due to outside regional development and traffic. In general,
housing densities, types of units, and lot sizes should be maintained in established residential areas. In
some cases, the desire to protect the character of existing neighborhoods may require remedial action to
eliminate uses that are not compatible or that are not appropriate for a specific area.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-12
ISSUE ANALYSIS: There is a need to protect the character of existing neighborhoods from
incompatible land uses.
4. Local versus-Regional Needs/Short-Term versus Long-Term Solutions
a. Circulation
Diamond Bar presently provides a number of “short cuts” for regional commuters during peak traffic
periods and during periods of local freeway congestion. The City may choose to take appropriate
measures to relieve regional congestion which would ultimately free up local roads for predominately
local use. The City of Diamond Bar should proactively and aggressively work with and lobby
adjacent/regional agencies to develop regional circulation solutions that directly benefit Diamond Bar
local access needs. Local community residents should be given an opportunity for participation in the
discussion of these needs and possible solutions.
ISSUE ANALYSIS: There is a need to prevent regional commuter traffic from impacting
local traffic and local activities.
E. LAND USE GOALS, OBJECTIVES, AND STRATEGIES
“IT IS THE OVERALL GOAL OF THE LAND USE ELEMENT TO ENSURE THAT THE LAND
USES AND DEVELOPMENT DECISIONS OF DIAMOND BAR MAINTAIN AND ENHANCE
THE QUALITY OF LIFE FOR ITS RESIDENTS.”
GOAL 1 “Consistent with the Vision Statement, maintain a mix of land uses which enhance the
quality of life of Diamond Bar residents, providing a balance of development and
preservation of significant open space areas to assure both economic viability and
retention of distinctive natural features of the community.”
Objective 1.1 Establish a land use classification system to guide the public and private use of land
within the City and its Sphere of Influence.
Strategies: 1.1.1 Identify residential land use categories to provide an appropriate range of
housing types for residential development within the City and its Sphere of
Influence.
(a) The maximum gross density of Rural Residential (RR) will be 1.0
dwelling unit per gross acre (1 du/ac) or less, depending upon the
establishment of a slope density ordinance.
(b) Designate existing developed single family detached residential parcels
as Low Density Residential (RL) on the Land Use Map. The maximum
density of such Low Density Residential parcels will be 3.0 dwelling
units per gross acre (3.0 du/ac), or existing density, whichever is greater.
(c) Designate existing single family detached subdivisions as Low Medium
Residential (RLM) on the Land Use Map. The maximum density of
Diamond Bar General Plan Land Use Element
July 25, 1995 I-13
Low Medium Residential areas will be 5.0 dwelling units per gross acre
(5.0 du/ac), or existing density, whichever is greater.
(d) Designate existing planned townhome, condominium, apartment, mobile
home, and other multiple family residential properties as Medium
Density Residential (RM) on the Land Use Map. Maintain a maximum
density of 12.0 dwelling units per gross acre (12 du/ac) within these
areas.
(e) Designate existing, and planned townhome, condominium, apartment,
and other multiple family residential properties as Medium High
Residential (RMH) on the Land Use Map. Maintain a maximum density
of 16.0 dwelling units per gross acre (16 du/ac) within these areas.
(f) Designate existing and proposed high density condominium and
apartment developments and other high density properties as High
Density Residential. (RH) on the Land Use Map. Maintain a maximum
density of 20.0 dwelling units per gross acre (20 du/ac) within these
areas.
(g) Develop a slope density ordinance which shall be applied to all land use
designations in the City. Such slope density shall reduce the number of
dwelling units otherwise designated for the property as a function of
average slope of the land in question in excess of 25 percent. Average
slope is defined as follows:
I = Contour interval in feet
Slope = 0.002296 I L L = Summation of length of all
A contours in feet
A = area in acres of parcel
considered
1.1.2 Ensure that the land use classification system provides adequate separation and
buffering of less active residential uses from more intense land uses, major
streets, and highways.
1.1.3 Identify commercial land use categories to provide for a range of retail and
service uses to serve City needs and to guide development within the City and its
Sphere of Influence.
(a) Encourage active pursuit of commercial development in Gateway
Corporate Center as a means of increasing City revenues.
(b) Establish General Commercial (C) areas to provide for regional,
freeway-oriented, and/or community retail and service commercial uses.
Development of General Commercial areas will maintain a floor area
ratio (FAR) between 0.25 and 1.00.
(c) Designate Commercial Office (CO) land use areas on diverse, mixed us
commercial retail, office and service properties. Development within
Commercial Office areas will maintain an FAR between 0.25 and 1.00.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-14
(d) Designate Professional Office (OP) areas to provide for the
establishment of office-based working environments for general,
professional, and administrative offices, as well as support uses.
Development within Professional Office areas will maintain an FAR
between 0.25 and 1.00.
1.1.4 Areas designated Light -Industrial (I) on the General Plan Land Use Map are to
provide for light industrial, research and development, and office-based industrial
firms seeking a pleasant and attractive working environment, as well as for
business support services, and commercial uses requiring more land area than is
available in General Commercial or Commercial Office areas. These areas will
maintain a maximum floor area ratio of 0.25 to 1.00.
1.1.5 The Public Facilities (PF) designation is designed to identify existing or
potential (future) sites for necessary public facilities or infrastructure
improvements. The primary purpose of land designated as Public Facilities, is to
provide areas for the conduct of public and institutional activities, such as public
schools, parks and water facilities, including but not necessarily limited to local,
State, and Federal agencies, special districts, and both public and private utilities.
These uses maintain development standards which do not exceed that of the most
restrictive adjacent designation.
1.1.6 Areas designated as Open Space (OS) provide recreational opportunities,
preservation of scenic and environmental values, protection of resources (water
reclamation and conservation), protection of public safety and preservation of
animal life. This designation also includes lands which may have been restricted
to open space by map restriction, deed (dedication, condition, covenant and/or
restriction), by an Open Space Easement pursuant to California Government
Code (CGC), Section 51070 et seq. and Section 64499 et seq. This designation
carries with it a maximum development potential of one single family unit per
existing parcel, unless construction was previously restricted or prohibited on
such properties by the County of Los Angeles.
1.1.7 Provide Park (PK) designations for existing and future public parks. Designate
the Diamond Bar Country Club as Golf Course (GC). Designate major private
recreational facilities (e.g. Little League ball fields, YMCA) as Private
Recreation (PR). The Private Recreation designation may be applied to lands
required to be set aside for recreational use which have not been dedicated to or
accepted by a public agency; no development may take place on these lands other
than open space uses specifically permitted by the applicable Planned Unit
Development and/or deed restrictions.
1.1.8 Areas designated as Planning Areas (PA) are designed to conserve open space
resources and are to be applied to properties where creative approaches are
needed to integrate future development with existing natural resources. All
proposed development within these designated areas shall require the formation
of a Specific Plan pursuant to the provisions of Government Code Section 65450.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-15
Land uses which may be appropriate within the planning areas shall be subject to
public hearings and approval of the City Council. Each Specific Plan must
incorporate innovation and superior design addressing the uniqueness of each
area and create a more desirable living environment than could be achieved
through conventional development.
1.1.9 Encourage the innovative use of land resources and development of a variety of
housing and other development types, provide a means to coordinate the public
and private provision of services and facilities, and address the unique needs of
certain lands by recognizing Specific Plan (SP) overlay designation:
(a) for large scale development areas in which residential, commercial,
recreational, public facilities, and other land uses may be permitted; and,
(b) large acreage property(ies) in excess of ten (10) acres that are proposed
to be annexed into the City.
At such time as development might be proposed, require formulation of a
specific plan pursuant to the provisions of Government Code Section 65450 for
the Sphere of Influence area that will protect its unique biological and open space
resources, create fiscal benefits for the City and enhance its infrastructure, while
minimizing future adverse impacts to both the human and natural environment of
the City, as well as the region (see Strategy 1.1.4 of the Circulation Element).
1.1.10 Within the Agricultural (AG) designation, permit single family residential at a
maximum density of 1.0 dwelling unit per 5 gross acres (1.0 du/5ac), agricultural
and compatible open space, public facility, and recreation uses (see also Land
Use Element Strategies 1.6.3 and 1.6.4).
Objective 1.2 Preserve and maintain the quality of existing residential neighborhoods while offering a
variety of housing opportunities, including mixed land uses.
Strategies: 1.2.1 Maintain a system of identifiable, complementary neighborhoods, providing
neighborhood identity signage, where appropriate, and ensuring that such signage
is well maintained over time.
1.2.2 Maintain the integrity of residential neighborhoods by discouraging through
traffic and preventing the creation of new major roadway connections through
existing residential neighborhoods.
1.2.3 Maintain residential areas which protect natural resources, hillsides, and scenic
areas.
(a) Development in hillside areas should be designed to be compatible with
surrounding natural areas, compatible to the extent practical with
surrounding development, aesthetically pleasing, and provide views from
development, but not at the expense of views of the development.
(b) Earthwork in hillside areas should utilize contour or landform grading.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-16
(c) Minimize grading to retain natural vegetation and topography.
1.2.4 Maintain residential areas which provide for ownership of single family housing
and require that new development be compatible with the prevailing character of
the surrounding neighborhood.
1.2.5 Enact Development Code Provisions for the development of second units on a
single family parcel. Ensure that the single family character and integrity of the
neighborhood be protected and that road, water, and sewer systems are capable of
supporting such development.
1.2.6 Broaden the range of, and encourage innovation in, housing types. Require
developments within all Residential areas to provide amenities such as common
usable, active open space and recreational areas, when possible.
1.2.7 Where consistent with the other provisions of the Diamond Bar General Plan,
encourage the provision of low and moderate cost housing (see also Housing
Goals, Objectives, and Strategies in this document).
Objective 1.3 Designate adequate land for retail and service commercial, professional services, and
other revenue generating uses in sufficient quantity to meet the City's needs.
Strategies: 1.3.1 Designate such lands for commercial use as are necessary to minimize sales tax
leakage out of Diamond Bar and to capture the City's fair share of sales tax
revenue.
(a) Identify retail needs which are not being met in the community.
(b) Define and implement an economic development program to attract
needed commercial uses to the City.
1.3.2 Encourage the development of businesses that take advantage of locations visible
from the freeway, where appropriate.
1.3.3 Encourage neighborhood serving retail and service commercial uses.
(a) Typical uses in the Commercial Office category include uses such as
general retail, specialty retail, markets, food and drug stores, commercial
services, restaurants, automotive repair and service, hardware and home
improvement centers, recreation, professional and business offices,
financial institutions, medical offices, and real estate offices.
1.3.4 Encourage the retention, rehabilitation, refurbishment, and/or expansion of
existing business establishments. Residentially compatible home occupations
where consistent with other provisions of the General Plan and Development
Code should be allowed subject to standards enacted to protect the privacy and
residential character of the neighborhood.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-17
1.3.5 Encourage revenue generating uses in locations that serve the City's needs.
(a) Professional Office areas are to provide for the establishment of office-
based working environments for general, professional, and
administrative offices, as well as necessary support uses.
(b) The Gateway Corporate Center in particular offers large lots with a
capacity for multi-story buildings: and is designed to take advantage of
unique locations with good freeway access, as well as access to
miscellaneous support uses. Buildings adjacent to the freeways along
Gateway Center Drive and Bridgegate Drive should have a maximum of
six (6) stories. Buildings along Copley Drive and Valley Vista Drive
should have a maximum of eight (8) stories. Trees native to the area
should be used to obstruct unsightly views.
1.3.6 Encourage consolidation of individual lots into a coordinated project; encourage
provision of enhanced amenities such as public art, plaza areas, open space and
landscaping, and pedestrian facilities in excess of required minimums; or
provision of housing within a mixed use project.
1.3.7 Undertake programs to target revitalization of existing commercial uses and
selected new retail uses needed to expand the range of goods and services
available to local residents and to generate needed sales tax revenue.
Objective 1.4 Designate adequate land for educational, cultural, recreational, and public service
activities to meet the needs of Diamond Bar residents.
Strategies: 1.4.1 Ensure that land owned and purchased for public use by public agencies is
designated on the Land Use Map for public purposes. Specific uses within the
Public Facilities category, as shown on the Land Use Map include water
facilities, fire stations, schools, parks, libraries, and similar facilities.
1.4.2 Promote joint development and use of parks and open space facilities with
adjacent jurisdictions; promote development of joint school/park sites and public
amenities.
1.4.3 When a public agency determines that land it owns is no longer needed, ensure
that the property is offered to other agencies, including the City of Diamond Bar,
for public uses, prior to conversion to private sector use.
1.4.4 Designate and pursue acquisition of a centralized site for use as a civic/multi-
purpose community center.
1.4.5 Pursue development of major joint use recreation and meeting facilities as part of
educational facility development.
1.4.6 Work with Tres Hermanos property owner(s) to incorporate, where appropriate,
educational/cultural, recreational and public services to include arterial highway
access to future schools.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-18
1.4.7 Work with neighboring jurisdictions and other agencies in the coordination and
designation of educational, cultural and recreational plans to include arterial
highway access to future schools.
Objective 1.5 Maintain a feeling of open space within the community by identifying and preserving an
adequate amount of open land.
Strategies: 1.5.1 Develop an Open Space program which will identify and preserve open space
land and rank its importance consistent with community needs, objectives and
financial capability. As part of the Slope Density Scale Ordinance, develop a
formula for the preservation of open space.
1.5.2 On all applications for subdivision and development approval, require the
submission of a title report or other acceptable documentation of deed and map
restrictions.
1.5.3 Land designated as Open Space by deed (dedication, condition, covenant and/or
restriction) by open space easement (CGC Section 51070 et seq.) or by map
restriction (explicit or previous subdivision) must comply with an established
review and decision making process prior to the recision, termination,
abandonment and/or removal of an open space dedication easement and/or
restriction.
Any decision to rescind, terminate, abandon, remove or modify a deed must be
supported by findings that the decision is of significant benefit to the City.
(a) Vacant land which deed is burdened by an open space dedication,
condition, covenant and/or restriction shall be required to be subject to
the abandonment process substantially similar to that which is set forth
in CGC Section 51090 et seq.
(b) Vacant land which is burdened by an open space easement pursuant to
CGC Section 51070 et seq. shall be required to be subject to the
abandonment process set forth in CGC 51090 et seq.
(c) Vacant land which is burdened by an explicit open space designation
delineated upon a map which was the result of a previous subdivision
approval shall be required to be subjected to at least one public hearing
before the City Council prior to any action to remove said restriction.
A decision to rescind, terminate, abandon, remove or modify an open space deed,
map restriction or OS land use designation must be preceded by both a finding by
the City Council that the decision confers a significant benefit on the City and a
favorable vote of the electorate at a regular or special election.
1.5.4 Vacant land and/or existing residential lots burdened by map restrictions which
delineate limitations or prohibitions related to building construction allowable
residential units, or other such non open space restrictions, shall be required to be
subject to a process established by the City Council prior to removal of such
restrictions.
(Amended
March 2, 1999
– City Council
Resolution No.
99-12)
Diamond Bar General Plan Land Use Element
July 25, 1995 I-19
(a) Vacant land burdened by non open space restrictions shall be required to
be subjected to public hearings before the Planning Commission and the
City Council before any action can be taken to remove any such
restrictions. Any decision to remove said map restrictions must be
supported by findings that such. removal is of significant benefit to the
City.
(b) Existing residential lots that are burdened by non open space map
restrictions shall be required to be subject to a process established by the
City Council prior to removal of any such restrictions.
1.5.5 Obtain Open Space land through feasible acquisition and management techniques
such as:
(a) Acquisition of land for parks and natural area conservation through a
process of entitlement review and density transfer among land uses of
like designation and entitlements review.
(b) Investigation of a bond issue for purchase of open space areas not
already protected by open space restrictions.
(c) Establishment of lighting and landscape districts for open space
improvements and maintenance.
(d) Through the entitlement process where the landowner/developer would
agree to sell at less than market value or dedicate property in exchange
for development rights.
1.5.6 To preserve significant environmental resources within proposed developments,
allow clustering or transferring of all or part of the development potential of the
entire site to a portion of the site, thus preserving the resources as open space,
and mandating the dedication of those resources to the City or a conservancy.
Objective 1.6 Consistent with the Vision Statement, provide flexibility in the planning of new
development as a means of encouraging superior land use by means such as open space
and public amenities.
Strategies: 1.6.1 A master plan shall be developed for each area of the City designated as a
Planning Area (PA). The location of each Planning Area is shown on Figure I-2.
Descriptions of each area and the contemplated land use designations are defined
as follows:
(a) Planning Area 1
PA-1 is located within the incorporated City south of the Pomona
Freeway west of Chino Hills Parkway. This 720± acre vacant area is part
of the larger Tres Hermanos Ranch property spanning Grand Avenue,
including property within the City of Chino Hills. PA-1 incorporates the
Diamond Bar General Plan Land Use Element
July 25, 1995 I-20
I-2 Proposed Land Use Map
I-2 Proposed Land Use Map
Diamond Bar General Plan Land Use Element
July 25, 1995 I-21
Agriculture (AG) land use designation permitting single family
residential at a maximum density of 1.0 dwelling unit per 5 gross acres.
Facilities appropriate for this site should be designed based upon a vision
for the future and not merely extend the patterns of the past. Such
facilities may include educational institutions, reservoir for practical and
aesthetic purposes, commercial developments which are not typical of
those found in the area and a variety of residential, churches, institutional
and other uses which are complimentary to the overall objective of
having a master planned area. Development within the Tres Hermanos
area should be designed so as to be a part of the Diamond Bar
community as well as compatible with adjacent lands.
(b) Planning Area 2
PA-2 is comprised of approximately 400 vacant acres located in two
non-contiguous areas. Sub-Area A consists of approximately 325 acres
located east of Diamond Bar Boulevard, north of Grand Avenue, south of
Gold Rush Drive, at the terminus of Highcrest Drive. Sub-Area B
consists of approximately 75 acres located east of Pantera Park.
Appropriate land uses for this 400 ± acre non-contiguous area include a
maximum of 130 single family detached residential dwelling units
concentrated along the anticipated extension of Highcrest Drive, a
minimum of 75 percent of the total 400 acre area set aside as dedicated
open space. A two-acre area located at the southeast comer of Diamond
Bar Boulevard and Gold Rush Drive should be developed for public
facility or commercial uses. In order to minimize environmental impacts
and maximize clustering, residential lots shall range in size from 6,000 to
10,000 square feet.
(c) Planning Area 3
PA-3 located south of Grand Avenue and east of Golden Springs Drive
incorporates approximately 55 acres of developed and undeveloped land.
Appropriate land uses for this multiple ownership area include mixed-use
commercial retail and office professional uses. PA-3 is comprised of
approximately 15 acres designated General Commercial (C) at the
intersection of Grand Avenue at Golden Springs Drive and Professional
Office (OP) uses for the remainder of the planning area. The maximum
intensity of development for this planning area is a FAR of 1.00.
(d) Planning Area 4
PA-4 consists of 82 vacant acres and is located west of Brea Canyon
Road, north of Peaceful Hills Road and south of South Pointe Middle
School. Land use designations appropriate for this planning area include
Park (PK), Public Facilities (PF) and Open Space (OS). The most
sensitive portion of the site shall be retained in permanent open space.
The site plan shall incorporate the planning and site preparation to
accommodate the development of Larkstone Park of a suitable size and
location to serve the neighborhood as approved by the City.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-22
1.6.2 Require that Planning Area projects provide a greater level of community
amenities and cohesiveness, achieve superior land use, and create a more
desirable living environment than could be achieved through conventional
subdivision design and requirements.
1.6.3 Designate the following larger properties as future Specific Plan (SP) areas. This
designation is an overlay to the base land use category providing for mixed use
projects in the future subject to approval of a Specific Plan consistent with
Government Code Section 65450. The issues to be addressed and the type and
maximum intensity of development within the future Specific Plan area is
defined below.
(a) Planning Areas 1-4 as described within Strategy 1.6.1
(b) Sphere of Influence
The 3,600 acre multiple ownership Sphere of Influence area contains unique
biological and open space resources. The formulation of a future Specific Plan
should incorporate provisions to protect existing resources while minimizing
future adverse impacts to both the human and natural environment of the City, as
well as the region (see Strategy 1.1.4 of the Circulation Element).
1.6.4 Encourage clustering within the most developable portions of project sites to
preserve open space and/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.
(a) Encourage offers to dedicate additional open space land to the City or a
conservancy.
1.6.5 Where feasible within new developments, encourage a mixture of
complementary development types (e.g. commercial, residential, recreational,
sales tax and employment-generating uses) which can be provided in an
integrated manner.
GOAL 2 “Consistent with the Vision Statement, manage land use with respect to the location,
density and intensity, and quality of development. Maintain consistency with the
capabilities of the City and special districts to provide essential services which
achieve sustainable use of environmental and manmade resources.”
Objective 2.1 Promote land use patterns and intensities which are consistent with the Resource
Management Element and Circulation Element.
Strategies: 2.1.1 Ensure that planning programs and individual development projects within and
affecting the City recognize, and are sensitive to, environmental resource
limitations.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-23
(a) Prior to approving new development or the intensification of existing
development within the City of Diamond Bar, ensure that the
environmental consequences of the proposed action have been
recognized adjacent jurisdictions, insist that there be a recognition and
appropriate mitigation of the environmental consequences of the
proposed action.
2.1.2 Ensure that new development utilizes feasible contemporary technologies to
reduce energy and water consumption, generation of solid and hazardous wastes,
and air and water pollutant emissions.
2.1.3 Ensure that time-specific issues are evaluated as part of the review of new
development and intensification of existing development. For example, when
deemed appropriate by the City, require prior to approval that biological
assessments be prepared through the seasonal cycle of plants and migration of
wildlife for a period of not less than one year.
Objective 2.2 Maintain an organized pattern of land use which minimizes conflicts between adjacent
land uses.
Strategies: 2.2.1 Require that new developments be compatible with surrounding land uses.
2.2.2 Prohibit the development of adjacent land uses with significantly different
intensities, or that have operating characteristics which could create nuisances
along a common boundary, unless an effective buffer can be created.
2.2.3 Where land uses of significantly different intensity or use are planned adjacent to
each other, ensure that individual site designs and operations are managed in
such a manner as to avoid the creation of nuisances and hazards.
2.2.4 Require that new developments be designed so-as to respect the views of existing
developments; provide view corridors which are oriented toward existing or
proposed community amenities, such as a park, open space, or natural features.
As part of the Development Code, adopt clear standards to identify the extent to
which views can, and will, be protected from impacts by new development and
intensification of existing development.
Objective 2.3 Ensure that future development occurs only when consistent with the availability and
adequacy of public services and facilities.
2.3.1 Through the environmental and development review processes, ensure that
adequate services, facilities, sand infrastructure are available to support each
development.
2.3.2 Require new development to pay its fair share of the public facilities and off-site
improvements needed to serve the proposed use.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-24
GOAL 3 “Consistent with the Vision Statement, maintain recognition within Diamond Bar and
the surrounding region as being a community with a well planned and aesthetically
pleasing physical environment.”
Objective 3.1 Create visual points of interest as a means of highlighting community identity.
Strategies: 3.1.1 Develop and locate City entry monuments, highlighting key community entry
points and open space areas to identify Diamond Bar to local and commuter
traffic.
3.1.2 Where feasible and appropriate, add areas for landscaping, such as in medians or
by widening parkways within the primary arterial roadway system, as a means of
traffic control, providing pedestrian amenities, and as an aesthetic feature for the
community.
3.1.3 Pursue the establishment and expansion of landscape maintenance districts as a
means of ensuring the ongoing maintenance of medians and community entry
statements, as well as maintenance of landscaping of hillsides along major
roadways.
3.1.4 Consider a program to place public art at prominent locations throughout the City
of Diamond Bar.
3.1.5 Encourage the provision and maintenance of neighborhood identification
signage.
Objective 3.2 Ensure that new development, and intensification of existing development, yields a
pleasant living, working, or shopping environment, and attracts interest of residents,
workers, shoppers, and visitors as the result of consistent exemplary design.
Strategies: 3.2.1 Within the urban residential portions of the City, require the incorporation of
open space and recreational areas into the design of new projects. Within
topographically rugged and rural areas, emphasize the preservation of natural
landforms and vegetation.
3.2.2 Require in the Development Code that setbacks from streets and adjacent
properties relate to the scale of the structure as well as the size of the street right-
of-way. Require that building setbacks along roadways be varied so as to avoid a
monotonous street scene.
3.2.3 Minimize the use of block walls unless they are needed for a specific screening,
safety, or sound attenuation purpose. Where feasible, provide instead a wide
open area with informal clusters of trees, defined by split rail, wrought iron,. or
similar open fencing. Where construction. of a- solid wall which will be visible
along a public street is necessary, provide landscaping such as trees, shrubs, or
vines to break the visual monotony, and soften the appearance of the wall, and to
reduce glare, heat, or reflection. Where solid walls currently exist along the
Diamond Bar General Plan Land Use Element
July 25, 1995 I-25
primary roadway system, and it is possible to retrofit landscape screens,
establish a funding mechanism for the construction of such screens.
3.2.4 Enhance pedestrian activity within residential, commercial, office, and light
industrial areas.
(a) Ensure that non-residential facilities are oriented to the pedestrian, by
the incorporation of seating areas, courtyards, landscaping, and' similar
measures.
(b) Utilize “street furniture” (decorative planters, bike racks, benches) to
create and enhance urban open spaces.
(c) Design commercial and office projects so as to have a central place,
main focus, or feature.
(d) Utilize varied building setbacks and staggered elevations to create plaza-
like areas which attract pedestrians, whenever possible.
3.2.5 Require that automobile service facilities and commercial loading areas be
oriented away from the street frontage and from residential edges wherever
possible to minimize sight and sound impacts.
3.2.6 Where the rear or sides of commercial, office, or other non-residential buildings
will be visible within a residential neighborhood, ensure that the visible
elevations will be treated in such a manner as to provide a pleasing appearance.
3.2.7 Ensure that commercial developments are designed with a precise concept for
adequate signage, including provisions for sign placement and number, as well as
sign scale in relationship to the building, landscaping, and readability as an
integral part of the signage concept. Ensure that signs are integrated into the
overall site and architectural design theme of commercial developments.
3.2.8 In conjunction with area utility companies, pursue a program of undergrounding
overhead utility lines.
3.2.9 Include within the Development Code requirements for the size and quantity of
trees to be planted within new development and intensification of existing
development.
3.2.10 New development shall comply with the City's Hillside Management Ordinance.
3.2.11 In Rural Residential (RR) minimize right-of-way width to the extent feasible.
Objective 3.3 Protect the visual quality and character of remaining natural areas, and ensure that
hillside development does not create unsafe conditions.
Strategies: 3.3.1 Balance the retention of the natural environment with its conversion to urban
forms.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-26
3.3.2 Promote incorporation of hillside features into project designs.
3.3.3 As part of the Development Code, maintain hillside development regulations that
are sensitive to natural contours and land forms
3.3.4 Limit grading to the minimum necessary.
3.3.5 Require that all manufactured slopes be landscaped and that, where practical,
landform grading and planting techniques be implemented in the construction of
manufactured slopes.
(a) Foliage used in planting palettes should be drought tolerant, fire resistant,
and have colors similar to those of native materials in the surrounding
area.
(b) Within landform graded slopes, plants should be grouped within swale
areas to more closely reflect natural conditions.
GOAL 4 “Consistent with the Vision Statement, encourage long-term and regional
perspectives in local land use decisions, but not at the expense of the Quality of Life
for Diamond Bar residents.”
Objective 4.1 Promote and cooperate in efforts to provide reasonable regional land use and
transportation/circulation planning programs.
Strategies: 4.1.1 Take a proactive role to coordinate Diamond Bar's land use plan with
those of surrounding cities and other agencies.
4.1.2 Consider the potential impacts of proposed Diamond Bar developments on
neighboring jurisdictions as part of the development review process. Notify
neighboring jurisdictions when considering changes to the City's existing land
use pattern.
4.1.3 Monitor the progress of major regional developments; cooperate with appropriate
City, County, State, and Regional organizations to achieve maximum interaction
and cooperation; participate fully in relevant regional development patterns.
4.1.4 Encourage coordination with adjacent cities and other agencies to lobby the State
and Federal government on regional issues which affect the City of Diamond
Bar.
4.1.5 Monitor and evaluate potential impacts upon the City of Diamond Bar, of major
proposed adjacent, local, and regional developments, in order to anticipate land
use, circulation, and economic impacts and related developmental patterns of the
City of Diamond Bar.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-27
4.1.6 Relate major regional impacts to planning action which might be required to
safeguard the best interests and Quality of Life of the City of Diamond Bar.
Objective 4.2 Maintain City boundaries which are reasonable in terms of existing service capabilities,
social and economic interdependencies, citizen desires, and City revenues and
expenditures.
Strategies: 4.2.1 Seek annexation of those areas which have primary access through
Diamond Bar and whose residents and businesses are most logically
served by the City.
4.2.2 Consider annexation of additional areas west of the City boundaries including
expansion of the adopted Sphere of Influence, where the following findings can
be made:
(a) Compatibility exists with the goals and desires of the people and the City
of Diamond Bar;
(b) The proposed annexation is consistent with goals and objectives of the
General Plan;
(c) Significant benefits will; be derived by the City and affected property
owners/residents upon annexation;
(d) There exists a significant social and economic interdependence and
interaction between the City of Diamond Bar and the area proposed for
annexation.
F. LAND USE PLAN
The Land Use Plan describes the extent of future development in Diamond Bar and identifies standards
for that development. The geographic locations of land uses are presented in the Land Use Map, Figure
I-2, and the standards for development and resulting General plan buildout are presented in the General
Plan Land Use Table I-3. Table I-4 presents a summary of potential residential and commercial growth
under the General Plan.
1. Land Use Designations
Land use designations are necessary to identify the type of development that is allowed in a given
location. While terms such as “residential”, “commercial”, and “industrial” are generally understood,
State general plan law requires a clear and concise description of the land use categories shown on the
Land Use Map.
The City of Diamond Bar Land Use Element provides for 18 land use designations. General Plan land use
categories are defined above in Section E - Land Use Goal, Objectives and Strategies. Strategy 1.1.1
outlines residential land use and includes five classifications ranging from rural residential to high density
residential use. Strategies 1.1.3 and 1.1.4 define commercial land uses for a range of retail and service
uses including general commercial, commercial office, professional office, and light industrial. Strategies
1.1.5 through 1.1.10 describe other land use categories including public facilities, open space, park,
Diamond Bar General Plan Land Use Element
July 25, 1995 I-28
planning area, agriculture and specific plan. The Land Use Plan Development Capacity Summary Table
I-3 illustrates these classifications, each of which has a residential density or a land use intensity.
Additional non-residential land use categories include public facilities, conservation open space, park,
golf course, private recreation, and planned preservation.
2. Land Use Intensity/Density
The Element uses certain terminology to describe the land use designations. The term “density” refers to
residential uses and to the population and development capacity of residential land. Density is described
in terms of dwelling units per gross acre of land (du/ac). For example, 50 dwelling units occupying 20
acres of land is 5.0 du/ac.
The land use designations, or categories, in this Element are described in terms of intensity and density.
The term “intensity” which applies to non-residential uses, refers to the extent of development on a parcel
of land or on a lot. It includes the total building square footage, building height, the floor area ratio,
and/or the percent of lot coverage. Intensity is often used to describe non-residential development levels,
but in a broader sense, intensity is used to express overall levels of both residential and non-residential
development types. In this Element, floor area ratio and building square footage are used as measures of
non-residential development intensity.
Floor Area Ratio (FAR) represents the ratio between the total gross floor area of all buildings on a lot and
the total area of that lot. To determine FAR, divide gross floor area of all buildings on a lot by the land
area of that lot. For example, Figure I-3 illustrates that a 10,000 square foot building on a 40,000 square
foot lot yields an FAR of 0.25:1. The FAR controls the intensity of use on a lot. A 0.25:1 FAR can yield a
building of one story in height which covers one-half of the lot area, or a taller building which covers less
of the lot and provides for more open space around the building.
State General Plan law requires that the Land Use Element indicate the maximum densities and intensities
allowed under each land use designation. The land use designations shown on the Land Use Map are
described in detail in this Element. Strategies 1.1.1 through 1.1.10 describe each land use designation
shown on the Land Use Map and provides a corresponding indication of maximum density or intensity of
developments.
Maximum allowable development on individual parcels of land is governed by these measures of density
or intensity. Table 1-3 identifies the acreage dedicated to each land use category. Table I-4 presents the
overall future development in Diamond Bar under General Plan buildout. Average residential densities
are 100% of the maximum permitted density. Average commercial/industrial FARs are based on existing
development patterns. For various reasons, many parcels in the community have not been developed to
their maximum density or intensity and, in the future, maximum development as described in this
Element can be expected to occur only on a limited number of parcels. Development at an intensity or
density between the expected and maximum levels can occur only where projects offer exceptional design
quality, important public amenities or benefits, or other factors that promote important goals and policies
of the General Plan. For the residential land use designations, projects are expected to build to a density at
least as high as the lowest density allowed by their respective designations.
Diamond Bar General Plan Land Use Element
July 25, 1995 I-29
I-3 Possible Building Configurations for 0.25:1 Floor Area Ratio
I-3 Possible Building Configurations for 0.25:1 Floor Area Ratio
Diamond Bar General Plan Land Use Element
July 25, 1995 I-30
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II. HOUSING ELEMENT
CITY OF
DIAMOND BAR
2013-2021
HOUSING ELEMENT
January 2014
City Council Resolution No. 2014-14
Diamond Bar 2013-2021 Housing Element
i January 2014
Contents
I. Introduction ................................................................................................................................. I-1
A. Community Context ..................................................................................................................... I-1
B. Role of Housing Element .............................................................................................................. I-2
C. Data Sources ................................................................................................................................. I-4
D. Public Participation ...................................................................................................................... I-4
E. Relationship to Other General Plan Elements ......................................................................... I-5
II. Housing Needs Assessment ...................................................................................................... II-1
A. Population Characteristics ..........................................................................................................II-1
1. Population Growth Trends ....................................................................................................... II-1
2. Age .............................................................................................................................................. II-2
3. Race and Ethnicity ................................................................................................................... II-3
B. Household Characteristics ..........................................................................................................II-3
1. Household Composition and Size .......................................................................................... II-3
2. Housing Tenure and Vacancy ................................................................................................ II-4
3. Overcrowding............................................................................................................................ II-5
4. Household Income ................................................................................................................... II-5
5. Overpayment ............................................................................................................................ II-5
C. Employment ...................................................................................................................................II-6
1. Current Employment ................................................................................................................ II-6
2. Projected Job Growth ............................................................................................................. II-8
D. Housing Stock Characteristics ....................................................................................................II-9
1. Housing Type and Growth Trends .......................................................................................... II-9
2. Housing Age and Conditions .................................................................................................. II-9
3. Housing Cost ............................................................................................................................ II-11
E. Special Needs ............................................................................................................................ II-12
1. Persons with Disabilities .......................................................................................................... II-12
2. Elderly ........................................................................................................................................ II-15
3. Large Households.................................................................................................................... II-15
4. Female-Headed Households ................................................................................................ II-16
5. Farm Workers............................................................................................................................ II-16
6. Homeless Persons .................................................................................................................... II-17
F. Assisted Housing at Risk of Conversion .................................................................................. II-18
G. Future Growth Needs ................................................................................................................ II-18
1. Overview of the Regional Housing Needs Assessment .................................................... II-18
2. 2014-2021 Diamond Bar Growth Needs ............................................................................. II-19
III. Resources and Opportunities .................................................................................................. III-1
A. Land Resources ............................................................................................................................ III-1
B. Financial and Administrative Resources ................................................................................. III-1
1. State and Federal Resources.................................................................................................. III-1
2. Local Resources ........................................................................................................................ III-2
C. Energy Conservation Opportunities ......................................................................................... III-4
IV. Constraints ................................................................................................................................. IV-1
A. Governmental Constraints ........................................................................................................ IV-1
1. Land Use Plans and Regulations ........................................................................................... IV-1
2. Development Processing Procedures ................................................................................IV-10
3. Development Fees and Improvement Requirements ....................................................IV-13
B. Non-Governmental Constraints ............................................................................................. IV-14
1. Environmental Constraints ....................................................................................................IV-14
2. Infrastructure Constraints ......................................................................................................IV-17
Diamond Bar 2013-2021 Housing Element
ii January 2014
3. Land Costs ............................................................................................................................... IV-17
4. Construction Costs ................................................................................................................. IV-18
5. Cost and Availability of Financing ...................................................................................... IV-18
C. Fair Housing ................................................................................................................................ IV-18
V. Housing Action Plan ................................................................................................................. V-1
A. Goals and Policies ....................................................................................................................... V-1
B. Housing Programs ........................................................................................................................ V-3
Conserving the Existing Supply of Affordable Housing ................................................................. V-3
1. Residential Neighborhood Improvement Program ............................................................ V-3
3. Single-Family Rehabilitation Program ................................................................................... V-4
4. Section 8 Rental Assistance Program .................................................................................... V-4
5. Preservation of Assisted Housing ............................................................................................ V-4
6. Mobile Home Park Preservation ............................................................................................. V-5
Assisting in the Provision of Housing .................................................................................................. V-5
7. First-Time Homebuyer Assistance Programs ......................................................................... V-5
8. Senior and Workforce Housing Development ..................................................................... V-6
Providing Adequate Housing Sites and Facilitating Infill Opportunities to Achieve a
Variety and Diversity of Housing ............................................................................................ V-7
9. Land Use Element and Zoning................................................................................................ V-7
10. Mixed Use Development ......................................................................................................... V-8
11. Second Units .............................................................................................................................. V-9
12. Emergency Shelters and Transitional/Supportive Housing ................................................ V-9
13. Redevelopment of Underutilized Sites .................................................................................. V-9
Removing Governmental Constraints ...........................................................................................V-10
14. Affordable Housing Incentives/Density Bonus ...................................................................V-10
15. Efficient Project Processing ...................................................................................................V-10
Promoting Equal Housing Opportunities .......................................................................................V-11
16. Fair Housing Program .............................................................................................................V-11
17. Reasonable Accommodation for Persons with Disabilities .............................................V-11
Appendix A – Evaluation of the Prior Housing Element
Appendix B – Residential Land Inventory
Appendix C – Public Participation Summary
Appendix D – City Council Resolution No. 2014-04
Diamond Bar 2013-2021 Housing Element
iii January 2014
List of Tables
Table II-1 Population Trends 1990-2013 – Diamond Bar vs. Los Angeles County ..........................II-2
Table II-2 Age Distribution – Diamond Bar vs. Los Angeles County .................................................II-2
Table II-3 Race/Ethnicity – Diamond Bar vs. Los Angeles County ...................................................II-3
Table II-4 Household Composition – Diamond Bar vs. Los Angeles County ..................................II-4
Table II-5 Household Tenure – Diamond Bar vs. Los Angeles County .............................................II-4
Table II-6 Overcrowding – Diamond Bar vs. Los Angeles County ...................................................II-5
Table II-7 Median Household Income - Diamond Bar vs. Los Angeles County .............................II-5
Table II-8 Overpayment by Income Category – Diamond Bar .......................................................II-6
Table II-9 Labor Force Characteristics – Diamond Bar vs. Los Angeles County............................II-7
Table II-10 Employment by Occupation – Diamond Bar ....................................................................II-7
Table II-11 Job Location for Diamond Bar Residents ...........................................................................II-7
Table II-12 2010-2020 Industry Employment Projections – Los Angeles County ..............................II-8
Table II-13 Housing by Type, 2000-2013 – Diamond Bar vs. Los Angeles County ............................II-9
Table II-14 Age of Housing Stock by Tenure – Diamond Bar vs. Los Angeles County ................. II-10
Table II-15 Residential Neighborhoods with Housing Rehabilitation Needs ................................. II-10
Table II-16 Income Categories and Affordable Housing Costs – Los Angeles County .............. II-11
Table II-17 Persons with Disabilities by Age – Diamond Bar ............................................................. II-13
Table II-18 Elderly Households by Tenure – Diamond Bar ................................................................. II-15
Table II-19 Household Size by Tenure – Diamond Bar ....................................................................... II-16
Table II-20 Household Type by Tenure – Diamond Bar ..................................................................... II-16
Table II-21 2014-2021 Regional Housing Growth Needs – Diamond Bar ....................................... II-19
Table IV-1 Residential Land Use Categories – Diamond Bar General Plan ................................... IV-2
Table IV-2 Residential Development Standards ................................................................................. IV-3
Table IV-3 Permitted Residential Development by Zoning District .................................................. IV-4
Table IV-4 Residential Parking Requirements ...................................................................................... IV-8
Table IV-5 Review Authority for Residential Development ............................................................. IV-10
Table IV-6 Planning and Development Fees ..................................................................................... IV-13
Table IV-7 Road Improvement Standards ......................................................................................... IV-14
Table V-1 Housing Implementation Program Summary ................................................................. V-12
Table V-2 Quantified Objectives, 2013-2021 City of Diamond Bar .............................................. V-13
List of Figures
Figure I-1 Regional Location – Diamond Bar ....................................................................................... I-3
Figure IV-1 Environmental Constraints ................................................................................................. IV-16
Diamond Bar 2013-2021 Housing Element
iv January 2014
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Diamond Bar 2013-2021 Housing Element I. Introduction
I-1 January 2014
I. INTRODUCTION
A. Community Context
The City of Diamond Bar is located in the southeast corner of Los Angeles County, at the
intersection of Los Angeles, Orange, and San Bernardino Counties. The City is situated at
the eastern end of the East San Gabriel Valley, adjacent to State Routes 57 and 60
(“Pomona Freeway”) as shown in Figure 1. Diamond Bar began as Rancho Los Nogales
(Rancho of the Walnut Trees) after a Spanish land grant in 1840. At its height, it was one
of the largest cattle and walnut ranches in Southern California. Until the mid-20th century,
this land was alternately combined and divided for various agricultural uses. In 1956, the
Christiana Oil Corporation and the Capital Oil Company, a subsidiary of the
Transamerica Corporation, purchased the Diamond Bar Ranch. A comprehensive
development plan was prepared and approved, making Diamond Bar one of the first
master-planned communities in Los Angeles County.
During the 1960s, suburban development spread eastward from the Los Angeles basin,
stimulating local housing and population growth as Diamond Bar's open hillsides were
replaced with homes. Despite its initial conception as a master-planned community,
Diamond Bar was not developed in an orchestrated manner while it remained an
unincorporated community. In March 1989, local voters approved incorporation in order
to assert stricter control over local development. On April 18, 1989, Diamond Bar became
the 86th city in Los Angeles County, and by 2007 had grown to a population of about
60,000 with approximately 18,000 housing units.
The ethnic composition of Diamond Bar is distinctly different from Los Angeles County as
a whole. Recent Census estimates revealed that the City’s demographic makeup
included 52% Asian and 21% white, compared to 14% and 28%, respectively, in Los
Angeles County. Hispanics comprised about 20% of the City’s residents, compared to
48% countywide.
The City's population is aging; between 1980 and 2010, the median age for Diamond Bar
increased from 27.5 years to 41.0 years. The senior population also grew; the share of the
population aged 65 years and above increased from 2% in 1980 to about 11% in 2010. In
terms of actual numbers, the senior population increased from approximately 600
persons in 1980 to nearly 6,500 persons in 2010. It is anticipated that the City will continue-
to experience growth in its senior population as the post-World War II “Baby Boom”
generation1 transitions into retirement.
In contrast to the size of its population, Diamond Bar has a relatively small employment
base. According to recent Census estimates2 there were approximately 15,655 jobs in the
City compared to about 18,500 housing units. Major employers include Allstate
Insurance, Travelers Insurance, South Coast Air Quality Management District, and the
Walnut Valley Unified School District. While the City actually lost jobs during the recessions
of the early 1990s and 2008-2012, the Southern California Association of Governments
1 “Baby Boomers” are those born between 1946 and 1964. In 2011 the first Boomers reached age 65.
2 SCAG based on 2006-2008 Census Transportation Planning Package
Diamond Bar 2013-2021 Housing Element I. Introduction
I-2 January 2014
projects a significant increase in employment in the region from about 7.2 million in 2010
to about 9.4 million in 2035.
Diamond Bar offers a variety of housing choices. Single-family homes account for about
72% of all units, while condominiums and apartments constitute about 9% and 17%
respectively of the housing stock. The City also contains two mobile home parks, which
comprise the remaining 2% of the housing stock. The housing stock generally is in good
physical condition. However, four older single-family neighborhoods with units
constructed during the 1960s and 1970s are showing signs of aging and deferred
maintenance and could be the focus for potential housing rehabilitation programs. The
City has one assisted housing project, The Seasons Apartments, providing 149 senior
housing units, all of which are reserved for low- and moderate-income households.
Housing prices for Diamond Bar are relatively high with the median single-family
detached home price of approximately $500,000 and a median price for condominiums
of approximately $245,000 in 2012. Although there are relatively few apartments in
Diamond Bar, representative rents for 2-bedroom apartments are typically $1,400 to
$1,500 per month.
Most of the easily buildable land in the City has already been developed, and much of
the remaining land is exposed to a variety of geotechnical and topographic conditions
that may constrain the development of lower-priced homes. In addition, inadequate
infrastructure may also act as a constraint to residential development. The majority of
future residential growth in Diamond Bar will occur in the underdeveloped northeast and
southern areas. Over 700 acres of the Tres Hermanos Ranch falls within the City and is
anticipated to include some multi-family housing on areas of moderate slope.
B. Role of Housing Element
Diamond Bar is faced with various important housing issues that include a balance
between employment and housing opportunities, a match between the supply of and
demand for housing, preserving and enhancing affordability for all segments of the
population, preserving the quality of the housing stock, and providing new types of
housing necessary to accommodate growth and the changing population. This Housing
Element provides policies and programs to address these issues.
Diamond Bar's Housing Element is an eight-year plan for the period 2013-2021, unlike
other General Plan elements which typically cover a 10- to 20-year planning horizon. This
Housing Element identifies strategies and programs that focus on: 1) conserving and
improving existing affordable housing; 2) providing adequate housing sites; 3) assisting in
the development of affordable housing; 4) removing governmental and other constraints
to the housing development; and 5) promoting equal housing opportunities.
Diamond Bar 2013-2021 Housing Element I. Introduction
I-3 January 2014
Figure I-1
Regional Location – Diamond Bar
Diamond Bar 2013-2021 Housing Element I. Introduction
I-4 January 2014
The Diamond Bar Housing Element consists of the following major components:
An analysis of the City's demographic and housing characteristics and trends
(Chapter II);
An evaluation of resources and opportunities available to address housing
issues (Chapter III);
A review of potential market, governmental, and environmental constraints to
meeting the City's identified housing needs (Chapter IV);
The Housing Action Plan for the 2013-2021 planning period (Chapter V); and
A review of the City’s accomplishments during the previous planning period
(Appendix A).
A detailed inventory of the suitable sites for housing development
(Appendix B)
C. Data Sources
In preparing the Housing Element, various sources of information were consulted. The
2010 Census and American Community Survey data provide the basis for population and
household characteristics. The Census remains the most comprehensive and widely
accepted source of information on demographic characteristics. Other sources of
information are used to supplement and provide reliable updates of the 2010 Census,
and include:
Population and demographic data provided by the State Department of
Finance;
Housing market information, such as home sales, rents, and vacancies;
Local and County public and nonprofit agency information on special needs
populations, services available to them, and gaps in the system;
Information on housing conditions based on City planning and code
enforcement activities.
D. Public Participation
Residents, businesses and interest groups participated in the City's Housing Element
update process and were an important component of the overall program. A public
workshop was conducted to discuss the Housing Element update, and prior to the public
hearings copies of the draft Element were disseminated for review throughout the
community at locations including City Hall, Diamond Bar Public Library and the City’s
website. In order to make citizens aware of the availability of the Housing Element, the
City placed advertisements in two daily publications, the Inland Valley Daily and the San
Gabriel Valley News.
Diamond Bar 2013-2021 Housing Element I. Introduction
I-5 January 2014
Following the public workshop and Planning Commission hearing, the draft Housing
Element was submitted to the State Department of Housing and Community
Development (HCD) for review. The element was then revised to respond to HCD
comments and the draft element was reviewed at a public hearing held by the City
Council prior to final adoption. Notices of all public hearings were posted in the local
newspaper and meetings are televised to provide broader outreach to the community.
Please see Appendix E for further information regarding the public participation program.
E. Relationship to Other General Plan Elements
The City of Diamond Bar General Plan consists of six elements: 1) Land Use; 2) Housing;
3) Resource Management; 4) Public Health and Safety; 5) Circulation; and 6) Public
Services and Facilities. This Housing Element builds upon the other General Plan elements
and is consistent with the policies and proposals set forth by the Plan. Examples of inter-
element consistency include: residential development capacities established in the Land
Use Element are incorporated within the Housing Element, and the discussion of
environmental constraints in the Housing Element is based upon information from the
Resource Management and Public Health and Safety elements.
As the General Plan is amended over time, the Housing Element will be reviewed for
consistency, and amended as necessary to maintain an internally consistent Plan.
SB 1087 of 2005 requires cities to provide a copy of their Housing Elements to local water
and sewer providers, and also requires that these agencies provide priority hookups for
developments with lower-income housing. The draft Housing Element was provided to
these agencies for review, and was again provided to them upon City Council adoption.
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Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-1 January 2014
II. HOUSING NEEDS ASSESSMENT
Diamond Bar lies in southeastern Los Angeles County, approximately 28 miles east of Los
Angeles. Diamond Bar's recorded history began with a Mexican land grant. On
March 30, 1840, Governor Juan Alvarado deeded 4,340 acres, which included Brea
Canyon and the eastern Walnut Valley, to Jose de la Luz Linares, who founded Rancho
Los Nogales, or Ranch of the Walnut Trees. Over time, and as the United States
government took over California, Rancho Los Nogales was divided and sold into multiple
land ranches, the largest of which was the Diamond Bar Ranch. The entire Diamond Bar
Ranch was acquired by the Transamerica Corporation in the 1950s for the purpose of
developing one of the nation’s first master-planned communities, named Diamond Bar.
The City of Diamond Bar was incorporated on April 18, 1989, and by 2013 had a
population of approximately 56,099. Diamond Bar is approximately 14.9 square miles in
area and is surrounded by the cities of Pomona to the north, Industry to the northwest,
the unincorporated community of Rowland Heights to the west, the Firestone Boy Scout
Reservation in unincorporated Los Angeles County to the south, and Chino Hills to the
east. According to recent Census data, the population’s median household income was
$90,153, approximately 63% higher than that of Los Angeles County ($55,476).
This chapter examines general population and household characteristics and trends,
such as age, race and ethnicity, employment, household composition and size,
household income, and special needs. Characteristics of the existing housing stock (e.g.,
number of units and type, tenure, age and condition, costs) are also addressed. Finally,
the City’s projected housing growth needs based on the 2014-2021 Regional Housing
Needs Assessment (RHNA)3 are examined.
The Housing Needs Assessment utilizes the most recent data from the U.S. Census,
California Department of Finance (DOF), California Employment Development Depart-
ment (EDD), Southern California Association of Governments (SCAG) and other relevant
sources. Supplemental data was obtained through field surveys and from private
vendors.
A. Population Characteristics
1. Population Growth Trends
Diamond Bar was incorporated in 1989 with much of its territory already developed. From
1990 to 2000, the City’s population grew by approximately 4.9%. From 2000 to 2013 the
City’s population was relatively stable, but declined by 188 residents (-0.3%) to an
estimated population of 56,099 (see Table II-1). The City’s 2013 population represents
approximately 0.6% of the county’s total population of 9,958,091.
3 State law establishes a timeframe of 2014-2021 for the RHNA and 2013-2021 for the Housing Element
planning period.
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-2 January 2014
Table II-1
Population Trends 1990-2013 –
Diamond Bar vs. Los Angeles County
1990 2000 2013
Growth
1990-2000
Growth
2000-2013
Diamond Bar 53,672 56,287 56,099 4.9% -0.3%
Los Angeles County 8,863,164 9,519,330 9,958,091 7.4% 4.6%
Source: U.S. Census, California Dept. of Finance Table E-5 (2013)
2. Age
Housing needs are influenced by the age characteristics of the population. Different age
groups require different accommodations based on lifestyle, family type, income level,
and housing preference. Table II-2 provides a comparison of the City’s and county’s
population by age group. The median age of the City’s population is approximately 6.2
years older than the county median. This is particularly apparent in the 45-64 age groups,
with this age cohort representing approximately 33% of the City’s population and only
25% of the county’s population.
Table II-2
Age Distribution –
Diamond Bar vs. Los Angeles County
Age Group
Diamond Bar Los Angeles County
Persons % Persons %
Under 5 years 2,389 4% 645,793 7%
5 to 9 years 2,864 5% 633,690 6%
10 to 14 years 3,760 7% 678,845 7%
15 to 19 years 4,498 8% 753,630 8%
20 to 24 years 3,974 7% 752,788 8%
25 to 29 years 3,268 6% 759,602 8%
30 to 34 years 2,842 5% 716,129 7%
35 to 39 years 3,354 6% 715,635 7%
40 to 44 years 4,121 7% 714,691 7%
45 to 49 years 4,776 9% 706,742 7%
50 to 54 years 5,095 9% 662,205 7%
55 to 59 years 4,448 8% 560,920 6%
60 to 64 years 3,669 7% 452,236 5%
65 to 69 years 2,428 4% 323,287 3%
70 to 74 years 1,592 3% 245,183 2%
75 to 79 years 1,092 2% 192,881 2%
80 to 84 years 771 1% 152,722 2%
85 years and over 603 1% 151,626 2%
Total 55,544 100% 9,818,605 100%
Median age 41.0 34.8
Source: 2010 Census, Table DP-1
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-3 January 2014
3. Race and Ethnicity
The racial and ethnic composition of the City differs significantly from the county’s
demographic makeup. For example, approximately 52% of City residents are Asian,
contrasted with 13.5% for the county as a whole. Non-Hispanic Whites make up the next
largest percentage of the population at 21.3%, which is 6.5% less than the county. The
percentage of Hispanics or Latinos residing in the City is 20.1%, substantially less than the
47.7% in the county as a whole (Table II-3).
Table II-3
Race/Ethnicity –
Diamond Bar vs. Los Angeles County
Racial/Ethnic Group
Diamond Bar Los Angeles County
Persons % Persons %
Not Hispanic or Latino 44,406 79.9% 5,130,716 52.3%
-White 11,812 21.3% 2,728,321 27.8%
-Black or African American 2,194 4.0% 815,086 8.3%
-American Indian/Alaska Native 67 0.1% 18,886 0.2%
-Asian 28,883 52.0% 1,325,671 13.5%
-Native Hawaiian/Pacific Islander 92 0.2% 22,464 0.2%
-Other races or 2+ races 1,358 2.4% 220,288 2.2%
Hispanic or Latino (any race) 11,138 20.1% 4,687,889 47.7%
Total 55,544 100.0% 9,818,605 100.0%
Source: 2010 Census, Table DP-1
B. Household Characteristics
1. Household Composition and Size
Household characteristics are important indicators of the type and size of housing
needed in a city. The Census defines a “household” as all persons occupying a housing
unit, which may include single persons living alone, families related through marriage or
blood, or unrelated persons sharing a single unit. Persons in group quarters such as
dormitories, retirement or convalescent homes, or other group living situations are
included in population totals but are not considered households.
Table II-4 provides a comparison of households by type for the City and Los Angeles
County as a whole as reported in recent Census data. Family households comprised
approximately 83% of all households in the City, about 15 percentage points higher than
the county composition of 68% of all households. There are far fewer non-family
households in Diamond Bar than the County as a whole (17% City vs. 32% county) as well
as singles living alone (13% City vs. 24% county). The City’s average household size of 3.10
is slightly higher than Los Angeles County as a whole (2.98). These statistics suggest that
that the need for large units in Diamond Bar may be slightly higher than other areas of
the county.
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-4 January 2014
Table II-4
Household Composition –
Diamond Bar vs. Los Angeles County
Household Type
Diamond Bar LA County
Households % Households %
Family households: 14,843 83% 2,194,080 68%
Husband-wife family 11,792 66% 1,480,665 46%
With own children under 18 years 5,202 29% 721,804 22%
Male householder, no wife present 886 5% 216,368 7%
With own children under 18 years 276 2% 92,161 3%
Female householder, no husband present 2,165 12% 497,047 15%
With own children under 18 years 802 4% 239,012 7%
Non-family households: 3,037 17% 1,047,124 32%
Householder living alone 2,308 13% 784,928 24%
Households with individuals under 18 years 7,008 39% 1,220,021 38%
Households with individuals 65 years and over 4,661 26% 790,386 24%
Total households 17,880 100% 3,241,204 100%
Average household size 3.1 2.98
Source: 2010 Census, Table DP-1
2. Housing Tenure and Vacancy
Housing tenure (owner versus renter) is an important indicator of the housing market.
Communities need an adequate supply of units available both for rent and for sale to
accommodate a range of households with varying income, family size and composition,
and lifestyle. Table II-5 provides a comparison of owner-occupied and renter-occupied
units in the City as compared to the county as a whole. It reveals that the level of
homeownership for the City (78.6%) is much higher than that for the county as a whole
(44.8%). Vacancy rates were relatively low in the City compared to the county, with an
overall vacancy rate of about 3% compared to 6% for Los Angeles County.
Table II-5
Household Tenure –
Diamond Bar vs. Los Angeles County
Housing Type
Diamond Bar LA County
Units % Units %
Occupied housing units 17,880 96.9% 3,241,204 94.1%
Owner-occupied housing units 14,513 78.6% 1,544,749 44.8%
Average household size of owner-occupied units 3.11 3.16
Renter-occupied housing units 3,367 18.2% 1,696,455 49.2%
Average household size of renter-occupied units 3.07 2.81
Vacant housing units 575 3.1% 203,872 5.9%
For rent 186 1.0% 104,960 3.0%
Rented, not occupied 15 0.1% 4,994 0.1%
For sale only 137 0.7% 26,808 0.8%
Sold, not occupied 36 0.2% 6,726 0.2%
For seasonal, recreational, or occasional use 71 0.4% 19,099 0.6%
All other vacants 130 0.7% 41,285 1.2%
Homeowner vacancy rate (%) 0.9 1.7
Rental vacancy rate (%) 5.2 5.8
Total housing units 18,455 100% 3,445,076 100%
Source: 2010 Census, Table DP-1
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
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3. Overcrowding
Overcrowding is often closely related to household income and the cost of housing. The
U.S. Census Bureau considers a household to be overcrowded when there is more than
one person per room, excluding bathrooms and kitchens, and severely overcrowded
when there are more than 1.5 occupants per room. Table II-6 summarizes the incidence
of overcrowding for Diamond Bar as compared to Los Angeles County as a whole.
Table II-6
Overcrowding –
Diamond Bar vs. Los Angeles County
Occupants per Room
Diamond Bar LA County
Units % Units %
Owner occupied units 14,950 100% 1,552,091 100%
1.01 to 1.50 234 1.6% 71,920 4.6%
1.51 to 2.00 0 0.0% 17,241 1.1%
2.01 or more 40 0.3% 4,877 0.3%
Renter occupied units 2,866 100% 1,665,798 100%
1.01 to 1.50 116 4.0% 163,166 9.8%
1.51 to 2.00 19 0.7% 86,760 5.2%
2.01 or more 0 0.0% 43,489 2.6%
Source: Census 2006-2010 ACS, Table B25014
According to recent Census data, overcrowding was more prevalent among renters
than for owner-occupied units. Approximately 4.7% of the City’s renter-occupied
households were overcrowded compared to 1.9% of owner-occupied households.
4. Household Income
Household income is a primary factor affecting housing needs in a community.
According to recent Census data, the median household income in Diamond Bar was
$90,153, approximately 63% higher than the Los Angeles County median income of
$55,476 (Table II-7).
Table II-7
Median Household Income -
Diamond Bar vs. Los Angeles County
Jurisdiction Median Income
% of County
Median Income
Diamond Bar 90,153 163%
Los Angeles County 55,476 100%
Source: U.S. Census, 2006-2010 ACS, Table DP-3
5. Overpayment
According to state housing policy, overpaying occurs when housing costs exceed 30% of
gross household income. Table II-8 displays recent estimates for overpayment by lower-
income households. According to SCAG, approximately 80% of all lower-income renter
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-6 January 2014
households and 71% of all lower-income owner households in Diamond Bar were
overpaying for housing. Extremely-low- and very-low-income households appeared to
suffer the greatest cost burden.
Although homeowners enjoy income and property tax deductions and other benefits
that help to compensate for high housing costs, lower-income homeowners may need to
defer maintenance or repairs due to limited funds, which can lead to deterioration. For
lower-income renters, severe cost burdens can require families to double up resulting in
overcrowding and related problems. The Housing Action Plan (Chapter V) includes
several programs that help to address the issue of overpayment, including Section 8
(Program 4), Preservation of Assisted Housing (Program 5), Senior and Workforce Housing
Development (Program 8), Land Use Element/Adequate Sites (Program 9), Mixed-Use
Development (Program 10), Second Units (Program 11), and Affordable Housing
Incentives/Density Bonus (Program 12). Other programs specifically designed for owner-
occupied units include Minor Home Repair and Single-Family Rehabilitation (Programs 2
and 3) and Mobile Home Park Preservation (Program 6).
Table II-8
Overpayment by Income Category – Diamond Bar
Income Category
Owners Renters
Households Percent Households Percent
Extremely low households 175 135
Households overpaying 175 100.0% 100 74.1%
Very low households 820 680
Households overpaying 530 64.6% 615 90.4%
Low households 1,700 580
Households overpaying 1,220 71.8% 405 69.8%
Subtotal: All lower-income households 2,695 1,395
Subtotal: Households overpaying 1,925 71.4% 1,120 80.3%
Moderate households 2,655 880
Households overpaying 1,685 63.5% 655 74.4%
Above moderate households 9,485 710
Households overpaying 2,545 26.8% 45 6.3%
Source: U.S. Department of Housing and Urban Development, CHAS, based on the 2006-2008 ACS. Table 15.
C. Employment
Employment is an important factor affecting housing needs within a community. The jobs
available in each employment sector and the wages for these jobs affect the type and
size of housing residents can afford.
1. Current Employment
Current employment and projected job growth have a significant influence on housing
needs during this planning period. Table II-9 shows that the City had a workforce of
29,229 persons, or 64.7% of the working-age population, as reported in recent Census
data. This table shows that the characteristics of the City’s population are similar to those
countywide. The proportion of the working age population in the labor force for
Diamond Bar is slightly lower than that of the county.
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-7 January 2014
Table II-9
Labor Force Characteristics –
Diamond Bar vs. Los Angeles County
Labor Force Status
Diamond Bar LA County
Persons % Persons %
Population 16 years and over 45,173 100% 7,602,252 100%
In labor force 29,229 64.7% 4,959,167 65.2%
Civilian labor force 29,169 64.6% 4,953,791 65.2%
Employed 27,655 61.2% 4,522,917 59.5%
Unemployed 1,514 3.4% 430,874 5.7%
Armed Forces 60 0.1% 5,376 0.1%
Not in labor force 15,944 35.3% 2,643,085 34.8%
Source: Census 2006-2010 ACS, Table DP3
Recent Census data indicate that 48.3% of the City’s working residents were employed in
management and professional occupations (Table II-10). A significant percentage of
workers (30.0%) were employed in sales and office related occupations. Approximately
11.3% were employed in service related occupations such as food servers and
beauticians. Blue collar occupations such as machine operators, assemblers, farming,
transportation, handlers and laborers constituted 10.4% of the workforce.
Table II-10
Employment by Occupation – Diamond Bar
Occupation
Diamond Bar
Persons %
Civilian employed population 16 years and over 27,655 100%
Management, business, science, and arts occupations 13,367 48.3%
Service occupations 3,122 11.3%
Sales and office occupations 8,299 30.0%
Natural resources, construction, and maintenance occupations 1,099 4.0%
Production, transportation, and material moving occupations 1,768 6.4%
Source: U.S. Census 2006-2010 ACS, Table DP3
According to recent Census data, 68.7% of employed Diamond Bar residents worked in
Los Angeles County, and approximately 13.8% of all workers were employed within the
City limits (Table II-11).
Table II-11
Job Location for Diamond Bar Residents
Workplace Location %
Worked in state of residence 99.8%
Worked in county of residence 68.7%
Worked in place of residence 13.8%
Worked outside county of residence 31.0%
Worked outside state of residence 0.2%
Source: Census 2006-2010 ACS, Table S0801
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-8 January 2014
2. Projected Job Growth
Future housing needs are affected by the number and type of new jobs created during
this planning period. Table II-12 shows projected job growth by industry for the Los
Angeles-Long Beach-Glendale MSA (Los Angeles County). Total employment in Los
Angeles County is expected to grow by 15.5% between 2010 and 2020. The economy is
expected to add about 658,000 new jobs and bring the employment of Los Angeles
County to about 4.9 million by 2020.
Table II-12
2010-2020 Industry Employment Projections –
Los Angeles County
NAICS
Code Industry Title
Annual Average
Employment Employment Change
2010 2020 Numerical Percent
Total Employment 4,246,700 4,904,300 657,600 15.5
Self-Employment (A) 337,500 366,900 29,400 8.7
Unpaid Family Workers (B) 3,300 3,400 100 3.0
Private Household Workers (C) 126,600 163,300 36,700 29.0
Total Farm 6,200 5,800 -400 -6.5
Total Nonfarm 3,773,100 4,364,900 591,800 15.7
1133,21 Mining and Logging 4,100 4,500 400 9.8
23 Construction 104,500 129,600 25,100 24.0
31-33 Manufacturing 373,200 362,500 -10,700 -2.9
22,42-49 Trade, Transportation, and Utilities 739,800 887,700 147,900 20.0
51 Information 191,500 211,700 20,200 10.5
52-53 Financial Activities 209,500 231,300 21,800 10.4
54-56 Professional and Business Services 527,500 640,600 113,100 21.4
61-62 Educational Services, Health Care and Social Assistance 522,000 660,000 138,000 26.4
71-72 Leisure and Hospitality 384,800 480,000 95,200 24.7
81 Other Services (excludes 814-Private Household Workers) 136,700 150,700 14,000 10.2
Government 579,600 606,300 26,700 4.6
Federal Government (D) 51,600 43,900 -7,700 -14.9
State and Local Government 528,000 562,400 34,400 6.5
State Government 80,700 88,100 7,400 9.2
Local Government 447,300 474,300 27,000 6.0
Data sources: U.S. Bureau of Labor Statistics' Current Employment Statistics (CES) March 2011 benchmark and Quarterly Census of Employment and
Wages (QCEW) industry employment.
Industry detail may not add up to totals due to independent rounding.
Notes:
(A) Self-Employed persons work for profit or fees in their own business, profession, trade, or farm. Only the unincorporated self-employed are included in
this category. The estimated and projected employment numbers include all workers who are primarily self-employed and wage and salary workers who
hold a secondary job as a self-employed worker.
(B) Unpaid family workers are those persons who work without pay for 15 or more hours per week on a farm or in a business operated by a member of the
household to whom they are related by birth or marriage.
(C) Private household workers are employed as domestic workers whose primary activities are to maintain the household. Industry employment is based on
QCEW.
(D) Temporary U.S. Census workers are included in the base and projected year employment numbers.
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-9 January 2014
D. Housing Stock Characteristics
This section presents an evaluation of the characteristics of the community’s housing
stock and helps in identifying and prioritizing needs. The factors evaluated include the
number and type of housing units, recent growth trends, age and condition, tenure,
vacancy, housing costs, affordability, and assisted affordable units at-risk of loss due to
conversion to market-rate units. A housing unit is defined as a house, apartment, mobile
home, or group of rooms, occupied as separate living quarters, or if vacant, intended for
occupancy as separate living quarters.
1. Housing Type and Growth Trends
As of 2013, the housing stock in Diamond Bar was comprised mostly of single-family
homes, making up about 81% of all units, while multi-family units comprised about 17% of
the total. The City’s housing stock contained 368 mobile home units. Table II-13 provides
a breakdown of the housing stock by type along with growth trends for the City
compared to the county as a whole for the period 2000-2013.
Table II-13
Housing by Type, 2000-2013 –
Diamond Bar vs. Los Angeles County
Structure Type
2000 2013 Growth
Units % Units % Units %
Diamond Bar
Single-family 15,107 84% 15,009 81% -98 -18.9%
Multi-family 2,519 14% 3,101 17% 582 112.1%
Mobile homes 333 1.9% 368 2.0% 35 6.7%
Total units 17,959 100% 18,478 100% 519 100%
Los Angeles County
Single-family 1,835,024 56% 1,948,879 56% 113,855 59.2%
Multi-family 1,379,277 42% 1,456,213 42% 76,936 40.0%
Mobile homes 56,605 2% 58,290 2% 1,685 0.9%
Total units 3,270,906 100% 3,463,382 100% 192,476 100%
Source: Cal. Dept. of Finance, Tables E-5 & E-8
2. Housing Age and Conditions
Housing age is often an important indicator of housing condition. Housing units built prior
to 1978 before stringent limits on the amount of lead in paint were imposed may have
interior or exterior building components coated with lead-based paint. Housing units built
before 1970 are the most likely to need rehabilitation and to have lead-based paint in a
deteriorated condition. Lead-based paint becomes hazardous to children under age six
and to pregnant women when it peels off walls or is pulverized by windows and doors
opening and closing.
Table II-14 shows the age distribution of the housing stock in Diamond Bar compared to
Los Angeles County as a whole.
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
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This table shows that the majority of housing units in Diamond Bar were constructed after
1970 (80%). These findings suggest that there may be a need for maintenance and
rehabilitation, including remediation of lead-based paint, for approximately 20% of the
units within the City’s housing stock.
Table II-14
Age of Housing Stock by Tenure –
Diamond Bar vs. Los Angeles County
Year Built
Diamond Bar LA County
Units % Units %
Built 2005 or later 149 1% 54,241 2%
Built 2000 to 2004 268 1% 109,255 3%
Built 1990 to 1999 875 5% 208,791 6%
Built 1980 to 1989 7,473 41% 403,248 12%
Built 1970 to 1979 5,932 32% 496,376 14%
Built 1960 to 1969 3,293 18% 518,500 15%
Built 1950 to 1959 268 1% 722,473 21%
Built 1940 to 1949 25 0% 396,035 12%
Built 1939 or earlier 73 0% 516,817 15%
Total units 18,356 100% 3,425,736 100%
Source: Census 2006-2010 ACS, Table DP-4
Due to the young age and relatively high property values, the majority of Diamond Bar's
housing stock is in very good condition. However, the City's Neighborhood Improvement
Office has identified four older neighborhoods characterized with older housing that is
beginning to exhibit signs of deferred maintenance such as peeling paint, worn roofs,
and cracked asphalt driveways. Table II-15 summarizes the physical problem conditions
of these older residential neighborhoods. The Action Plan establishes a program directed
at improving housing stock in these areas through targeted rehabilita tion assistance.
Fewer than 100 units are estimated to need rehabilitation citywide, and no units require
replacement.
Table II-15
Residential Neighborhoods with Housing Rehabilitation Needs
Neighborhood Characteristics Problem Conditions
#1 Northwest Diamond Bar:
Happy Hollow/Sunset Crossing/Prospectors
- Land use: single-family residential
- Constructed 1962 - 1973
- Deferred maintenance
- Cracked asphalt driveways
#2 Northwest Diamond Bar:
Ballena/Laspino/Pinto Mesa
- Land use: single-family residential
- Constructed 1964 - 1967
- Deferred maintenance
- Cracked asphalt driveways
#3 Central Diamond Bar:
Moonlake/Northhampton
- Land use: single-family residential
- Constructed 1965 – 1979
- Deferred maintenance
- Cracked asphalt driveways
#4 Central Diamond Bar:
Castle Rock/Pathfinder
- Land use: single-family residential
- Constructed ca. 1964
- Deferred maintenance
- Cracked asphalt driveways
Source: City of Diamond Bar, Office of Neighborhood Improvement.
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II-11 January 2014
3. Housing Cost
Housing Affordability Criteria
State law establishes five income categories for purposes of housing programs based on
the area (i.e., county) median income (“AMI”): extremely-low (30% or less of AMI), very-
low (31-50% of AMI), low (51-80% of AMI), moderate (81-120% of AMI) and above
moderate (over 120% of AMI). Housing affordability is based on the relationship between
household income and housing expenses. According to HUD and the California
Department of Housing and Community Development, housing is considered
“affordable” if the monthly payment is no more than 30% of a household’s gross income.
In some areas such as Los Angeles County, these income limits may be increased to
adjust for high housing costs.
Table II-16 shows affordable rent levels and estimated affordable purchase prices for
housing in Diamond Bar (and Los Angeles County)4 by income category. Based on state-
adopted standards, the maximum affordable monthly rent for extremely-low-income
households is $640, while the maximum affordable rent for very-low-income households is
$1,068. The maximum affordable rent for low-income households is $1,708, while the
maximum for moderate-income households is $1,944.
Maximum purchase prices are more difficult to determine due to variations in mortgage
interest rates and qualifying procedures, down payments, special tax assessments,
homeowner association fees, property insurance rates, etc. With this caveat, the
maximum home purchase prices by income category shown in Table II-16 have been
estimated based on typical conditions.
Table II-16
Income Categories and Affordable Housing Costs –
Los Angeles County
2013 County Median Income = $64,800 Income Limits Affordable Rent Affordable Price (est.)
Extremely Low (<30%) $25,600 $640 --
Very Low (31-50%) $42,700 $1,068 $140,000
Low (51-80%) $68,300 $1,708 $235,000
Moderate (81-120%) $77,750 $1,944 $280,000
Above moderate (120%+) $77,750+ $1,944+ $280,000+
Assumptions:
-Based on a family of 4
-30% of gross income for rent or PITI
-10% down payment, 4.5% interest, 1.25% taxes & insurance, $200 HOA dues
Source: Cal. HCD; J.H. Douglas & Associates
For-Sale Housing
Housing sales price statistics for calendar year 2012 show that single-family detached
homes sold for a median price of about $500,000 while condos were more affordable,
with a median price of $245,000.
Based on the estimated affordable purchase prices shown in Table II-16, a substantial
percentage of for-sale condo units were affordable to moderate-income residents.
4 Affordable rent and purchase prices are based on county median income.
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II-12 January 2014
These data illustrate the fact that public subsidies are generally required to reduce sales
prices to a level that is affordable to lower-income buyers. At a median price of $245,000
there is a “gap” of about $100,000 between the market price and the maximum price a
very-low-income household can afford to pay for a condo. These statistics illustrate why
affordable housing strategies generally focus on rental rather than ownership housing,
due to the smaller “affordability gap” for rental units.
Rental Housing
A recent internet survey5 showed typical rental rates for 2-bedroom apartments in
Diamond Bar of $1,400 to $1,500 per month. When market rents are compared to the
amounts lower-income households can afford to pay (Table II-16), it is clear that very-
low- and extremely-low-income households have a difficult time finding housing without
overpaying. The gap between market rent for a typical 2-bedroom 1-bath apartment
and affordable rent at the very-low-income level is about $400 - $500 per month, while
the gap at the extremely-low-income level is about $800 - $900 per month. However, at
the low-income and moderate-income levels, households are much more likely to find
affordable rentals.
E. Special Needs
Certain groups have greater difficulty in finding decent, affordable housing due to
special circumstances. Such circumstances may be related to one’s employment and
income, family characteristics, disability, or other conditions. As a result, some Diamond
Bar residents may experience a higher prevalence of overpayment, overcrowding, or
other housing problems.
State Housing Element law defines “special needs” groups to include persons with
disabilities, the elderly, large households, female-headed households with children,
homeless people, and farm workers. This section contains a discussion of the housing
needs facing each of these groups.
1. Persons with Disabilities
According to recent Census estimates, approximately 7% of non-institutionalized
Diamond Bar residents reported some type of disability (see Table II-17). As might be
expected, those aged 65 and over reported the highest disability rates. Approximately
34% of seniors reported some type of disability, compared to only 4% for persons
between age 18 and 64. The most frequently reported disabilities included ambulatory
difficulty (2.2% of the working age population and 26.1% of the senior population).
Housing opportunities for those with disabilities can be maximized through housing
assistance programs and providing universal design features such as widened doorways,
ramps, lowered countertops, single-level units and ground floor units.
5 www.apartmenthunterz.com, accessed October 27, 2013
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-13 January 2014
Table II-17
Persons with Disabilities by Age –
Diamond Bar
Disability by Age Persons Percent
Under Age 5 - total persons 2,589 --
With a hearing difficulty 24 0.9%
With a vision difficulty 24 0.9%
Age 5 to 17 - total persons 9,429
With a hearing difficulty 12 0.1%
With a vision difficulty 33 0.3%
With a cognitive difficulty 132 1.4%
With an ambulatory difficulty 13 0.1%
With a self-care difficulty 42 0.4%
Age 18 to 64 - total persons 36,976
With a hearing difficulty 338 0.9%
With a vision difficulty 124 0.3%
With a cognitive difficulty 502 1.4%
With an ambulatory difficulty 804 2.2%
With a self-care difficulty 378 1.0%
With an independent living difficulty 664 1.8%
Age 65 and over* - total persons 6,574
With a hearing difficulty 812 12.4%
With a vision difficulty 398 6.1%
With a cognitive difficulty 675 10.3%
With an ambulatory difficulty 1,715 26.1%
With a self-care difficulty 828 12.6%
With an independent living difficulty 1,288 19.6%
Source: U.S. Census, 2009-2011 ACS Table S1810
Note: Totals may exceed 100% due to multiple disabilities per person
The Housing Action Plan includes several programs that address the needs of this group,
including Program 2 – Minor Home Repair, Program 3 – Single Family Rehabilitation,
Program 4 – Section 8 Rental Assistance, Program 5 – Preservation of Assisted Housing,
Program 6 – Mobile Home Park Preservation, Program 8 – Senior and Workforce Housing
Development, Program 9 – Land Use Element (adequate sites), Program 11 – Second
Units, Program 12 – Affordable Housing Incentives/Density Bonus, Program 12 –
Emergency Shelters and Transitional Housing, Program 16 – Fair Housing, and Program 17
– Reasonable Accommodations.
Developmental Disabilities
As defined by federal law, “developmental disability” means a severe, chronic disability
of an individual that:
Is attributable to a mental or physical impairment or combination of mental and
physical impairments;
Is manifested before the individual attains age 22;
Is likely to continue indefinitely;
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II-14 January 2014
Results in substantial functional limitations in three or more of the following areas of
major life activity: a) self-care; b) receptive and expressive language; c) learning;
d) mobility; e) self-direction; f) capacity for independent living; or g) economic
self-sufficiency; and
Reflects the individual’s need for a combination and sequence of special,
interdisciplinary, or generic services, individualized supports, or other forms of
assistance that are of lifelong or extended duration and are individually planned
and coordinated.
The Census does not record developmental disabilities as a separate category of
disability. According to the U.S. Administration on Developmental Disabilities, an
accepted estimate of the percentage of the population that can be defined as
developmentally disabled is 1.5 percent. Many developmentally disabled persons can
live and work independently within a conventional housing environment. More severely
disabled individuals require a group living environment where supervision is provided. The
most severely affected individuals may require an institutional environment where
medical attention and physical therapy are provided. Because developmental
disabilities exist before adulthood, the first issue in supportive housing for the
developmentally disabled is the transition from the person’s living situation as a child to
an appropriate level of independence as an adult.
The California Department of Developmental Services (DDS) currently provides
community-based services to approximately 243,000 persons with developmental
disabilities and their families through a statewide system of 21 regional centers, four
developmental centers, and two community-based facilities. The San Gabriel-Pomona
Regional Center (SG/PRC) located in Pomona (http://www.sgprc.org/) provides services
for people with developmental disabilities in San Gabriel. The SG/PRC is a private, non -
profit community agency that contracts with local businesses to offer a wide range of
services to individuals with developmental disabilities and their families.
There is no charge for diagnosis and assessment for eligibility. Once eligibility is
determined, most services are free regardless of age or income. There is a requirem ent
for parents to share the cost of 24-hour out-of-home placements for children under age
18. This share depends on the parents' ability to pay. There may also be a co -payment
requirement for other selected services.
Regional centers are required by law to provide services in the most cost-effective way
possible. They must use all other resources, including generic resources, before using any
regional center funds. A generic resource is a service provided by an agency that has a
legal responsibility to provide services to the general public and receives public funds for
providing those services. Some generic agencies may include the local school district,
county social services department, Medi-Cal, Social Security Administration, Department
of Rehabilitation and others. Other resources may include natural supports. This is help
that disabled persons may get from family, friends or others at little or no cost.
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II-15 January 2014
2. Elderly
Recent Census data indicate that there were 2,706 households in Diamond Bar where
the householder was 65 or older (Table II-18). Many elderly persons are dependent on
fixed incomes or have disabilities. Elderly homeowners may be physically unable to
maintain their homes or cope with living alone. The housing needs of this group can be
addressed through smaller units, second units on lots with existing homes, shared living
arrangements, congregate housing and housing assistance programs.
Table II-18
Elderly Households by Tenure –
Diamond Bar
Householder Age
Owner Renter
Households % Households %
Under 65 years 12,500 84% 2,610 91%
65 to 74 years 1,687 11% 147 5%
75 to 84 years 617 4% 84 3%
85 years and over 146 1% 25 1%
Total Households 14,950 100% 2,866 100%
Source: U.S. Census 2006-2010 ACS, Table B25007
The elderly tend to have higher rates of disabilities than younger persons, therefore many
of the programs noted in the previous section also apply to seniors since their housing
needs include both affordability and accessibility.
3. Large Households
Household size is an indicator of need for large units. Large households are defined as
those with five or more members. Approximately 40% of owner households and 45% of
renter households in the City have only one or two members. About 7% of renter
households and about 13% of owners were large households with 5 persons or more
(Table II-19). This distribution indicates that the need for large units with four or more
bedrooms is expected to be significantly less than for smaller units. However, large
families needing units with more bedrooms, generally face higher housing costs, and as a
result may benefit from several types of assistance. The Housing Action Plan includes
several programs that address the needs of this group, including Program 2 – Minor Home
Repair, Program 3 – Single Family Rehabilitation, Program 4 – Section 8 Rental Assistance,
Program 5 – Preservation of Assisted Housing, Program 6 – Mobile Home Park
Preservation, Program 8 – Senior and Workforce Housing Development, Program 9 – Land
Use Element (adequate sites), Program 11 – Second Units, and Program 12 – Affordable
Housing Incentives/Density Bonus.
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-16 January 2014
Table II-19
Household Size by Tenure –
Diamond Bar
Householder Age
Owner Renter
Households % Households %
1 person 1,986 13% 612 21%
2 persons 4,090 27% 678 24%
3 persons 3,405 23% 846 30%
4 persons 3,407 23% 519 18%
5 persons 1,207 8% 182 6%
6 persons 648 4% 19 1%
7 persons or more 207 1% 10 0%
Total Households 14,950 100% 2,866 100%
Source: U.S. Census 2006-2010 ACS, Table B25009
4. Female-Headed Households
Of the 17,816 households in the City, approximately 9% of owner households and 16% of
renter households were headed by a female (Table II-20).
Table II-20
Household Type by Tenure –
Diamond Bar
Household Type
Owner Renter
Households % Households %
Married couple family 10,506 70% 1,353 47%
Male householder, no wife present 722 5% 196 7%
Female householder, no husband present 1,420 9% 462 16%
Non-family households 2,302 15% 855 30%
Total Households 14,950 100% 2,866 100%
Source: U.S. Census 2006-2010 ACS, Table B11012
The Housing Action Plan includes several programs that address the needs of female-
headed households, including Program 2 – Minor Home Repair, Program 3 – Single Family
Rehabilitation, Program 4 – Section 8 Rental Assistance, Program 5 – Preservation of
Assisted Housing, Program 6 – Mobile Home Park Preservation, Program 8 – Senior and
Workforce Housing Development, Program 9 – Land Use Element (adequate sites),
Program 11 – Second Units, Program 12 – Affordable Housing Incentives/Density Bonus,
and Program 12 – Emergency Shelters and Transitional Housing.
5. Farm Workers
Farm workers are traditionally defined as persons whose primary income is from seasonal
agricultural work. Diamond Bar was at one time one of the largest working cattle ranches
in the western United States. However, urban development and shifts in the local
economy have significantly curtailed agricultural production within Los Angeles County.
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-17 January 2014
Today, Diamond Bar is a mostly developed city, with a strong local economy that is no
longer tied to an agricultural base.
According to recent Census estimates6, about 41 Diamond Bar residents were employed
in agricultural occupations.
The nearest agricultural area to Diamond Bar is in San Bernardino County to the east.
Since there are no agricultural operations within Diamond Bar and housing costs are
significantly lower in the Inland Empire, there is no apparent need for farm worker
housing in the City.
6. Homeless Persons
Homelessness is a continuing problem throughout California and urban areas
nationwide. During the past two decades, an increasing number of single persons have
remained homeless year after year and have become the most visible of all homeless
persons. Other persons (particularly families) have experienced shorter periods of
homelessness. However, they are often replaced by other families and individuals in a
seemingly endless cycle of homelessness.
A homeless count conducted by the Los Angeles Homeless Services Authority (LAHSA) in
January 2013 indicated that on any given day there are an estimated 53,798 homeless
persons Los Angeles County. These include families that might be displaced through
evictions, women and children displaced through abusive family life, persons with
substance abuse problems, veterans, or persons with serious mental illness. Diamond Bar
is located within the San Gabriel Valley Service Planning Area (SPA), which has a 2013
homeless estimate of 4,444 people. Estimates of the homeless population for each
jurisdiction are not provided by LAHSA.
Senate Bill 2 of 2007 requires that jurisdictions quantify the need for emergency shelters
and determine whether existing facilities are adequate to serve the need. If adequate
existing facilities are not available, the law requires jurisdictions to identify areas where
new facilities are permitted “by-right” (i.e., without requiring discretionary approval such
as a use permit), or to accommodate the need through a multi-jurisdictional agreement.
Conversations with police and other City staff indicated that there are no known
homeless persons in Diamond Bar. This is likely due to the suburban nature of the
community, and the fact that social services are more readily available in more
urbanized areas. This was corroborated by the 2010 Census homeless counts, which
reported no homeless persons in Diamond Bar. Although homelessness is not a major
problem in Diamond Bar, the City has amended its zoning regulations to allow
emergency shelters by-right in the Light Industry.
Although there are currently no emergency shelter or transitional housing facilities within
Diamond Bar, a number of such facilities and supportive services are available in nearby
cities such as Pomona and Whittier. In addition, the San Gabriel Valley Council of
Governments recently initiated a study of homelessness, guided by the Homeless
6 SCAG, 2012 based on 2005-2009 ACS
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-18 January 2014
Services Steering Committee7. This study is expected to develop recommendations
toward a comprehensive, multi-jurisdictional strategy for addressing the needs of the
homeless in the valley.
F. Assisted Housing at Risk of Conversion
This section identifies residential projects in the City that are under an affordability
restriction, along with those housing projects that are at risk of losing their low-income
affordability restrictions within the ten-year period from 2013 to 2023. This information is
used in establishing quantified objectives for units that can be conserved during this
planning period. The inventory of assisted units includes all units that have been assisted
under any federal Department of Housing and Urban Development (HUD), state, local
and/or other programs.
The City of Diamond Bar has one assisted housing project for seniors, the 149 -unit Seasons
Apartments (formerly “Heritage Park”). Constructed in 1988, this project predates City
incorporation and was originally financed under the Los Angeles County Multi-family
Mortgage Revenue Bond program. The project was refinanced in November, 1999 under
the California Community Development Authority's Multifamily Housing Re-funding Bond.
According to the terms of the new bond agreement, income restrictions for residents
and corresponding rent limits were set. For the duration of the bond which expires
12/01/2034, all units will be affordable: 30 units (20%) will be very-low-income at 50% AMI,
82 units (55%) will be low-income at 80% AMI, and 37 units (25%) will be moderate-income
defined as 100% AMI. The Seasons Apartments are owned by the Corporate Fund for
Housing, a non-profit organization. Long-term affordability of the project is assured for the
life of the bond (2034). There are no assisted housing units in the City of Diamond Bar at
risk of conversion.
G. Future Growth Needs
1. Overview of the Regional Housing Needs Assessment
The Regional Housing Needs Assessment (RHNA) is a key tool for local governments to
plan for anticipated growth. The RHNA quantifies the anticipated need for housing within
each jurisdiction for the 5th Housing Element cycle extending from January 2014 to
October 2021. Communities then determine how they will address this need through the
process of updating the Housing Elements of their General Plans.
The RHNA was adopted by the Southern California Association of Governments (SCAG)
in October 2012. The future need for housing is determined primarily by the forecasted
growth in households in a community. Each new household created by a child moving
out of a parent’s home or by a family moving to a community for employment creates
the need for a housing unit. The housing need for new households is then adjusted to
maintain a desirable level of vacancy to promote housing choice and mobility. An
adjustment is also made to account for units expected to be lost due to demolition,
natural disaster, or conversion to non-housing uses. The sum of these factors – household
7 http://www.sgvcog.org/index.cfm/89807/Homeless-Services-Steering-Committee.cfm
Diamond Bar 2013-2021 Housing Element II. Housing Needs Assessment
II-19 January 2014
growth, vacancy need, and replacement need – determines the construction need for
a community. Total housing need is then distributed among four income categories on
the basis of the county’s income distribution, with adjustments to avoid an over-
concentration of lower-income households in any community.
2. 2014-2021 Diamond Bar Growth Needs
The total housing growth need for the City of Diamond Bar during the 2014-2021 planning
period is 1,146 units. This total is distributed by income category as shown in Table II-21.
Table II-21
2014-2021 Regional Housing Growth Needs –
Diamond Bar
Very Low Low Moderate
Above
Moderate Total
308* 182 190 466 1,146
*Per state law, half of the very-low units are assumed to be in the extremely low category
Source: SCAG 2012
It should be noted that SCAG did not identify growth needs for the extremely-low-
income category in the adopted RHNA. As provided in Assembly Bill (AB) 2634 of 2006,
jurisdictions may determine their extremely-low-income need as one-half the need in the
very-low category.
The City’s inventory of land to accommodate the RHNA allocation is discussed in the
Resources and Opportunities chapter.
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Diamond Bar 2013-2021 Housing Element III. Resources and Opportunities
III-1 January 2014
III. RESOURCES AND OPPORTUNITIES
A variety of resources are available for the development, rehabilitation, and preservation
of housing in the City of Diamond Bar. This chapter provides a description of the land
resources and adequate sites to address the City’s regional housing need alloc ation,
and discusses the financial and administrative resources available to support the
provision of affordable housing. Additionally, opportunities for energy conservation that
can lower utility costs and increase housing affordability are addressed.
A. Land Resources
Section 65583(a)(3) of the Government Code requires Housing Elements to contain an
“inventory of land suitable for residential development, including vacant sites and sites
having potential for redevelopment, and an analysis of the relationship of zoning and
public facilities and services to these sites.” A detailed analysis of vacant land and
potential redevelopment opportunities is provided in Appendix B, Table B-1, which shows
that the City’s land inventory, including projects approved and the potential
development of vacant and underutilized parcels, is sufficient to accommodate the
RHNA for this planning period in all income categories.
A discussion of public facilities and infrastructure needed to serve future development is
contained in Section IV. B, Non-Governmental Constraints. There are currently no known
service limitations that would preclude the level of development described in the RHNA,
although developers will be required to pay fees or construct public improvements prior
to or concurrent with development.
B. Financial and Administrative Resources
1. State and Federal Resources
Community Development Block Grant Program (CDBG) - Federal funding for
housing programs is available through the Department of Housing and Urban Develop -
ment (HUD). Diamond Bar participates in the Community Development Block Grant
(CDBG) program and receives its allocation of CDBG funds through the Los Angeles
County Housing and Community Development Department. The CDBG program is very
flexible in that the funds can be used for a wide range of activities. The eligible activities
include, but are not limited to, acquisition and/or disposition of real estate property,
public facilities and improvements, relocation, rehabilitation and construction of housing,
homeownership assistance, and clearance activities. In 2002 the City Council approved
the establishment of a Home Improvement Program (HIP) to provide housing
rehabilitation assistance to qualified low- and moderate-income households. CDBG
funds are allocated to the HIP on an annual basis. HIP funds are used for exterior property
improvements and for repairs to alleviate health and safety issues and to correct code
violations. In addition, HIP funds may be used to improve home access to disabled
persons and for the removal of lead based paint hazards.
The City’s CDBG allocation for the 2013-2014 Program Year was $301,190, which included
an allocation for the HIP of $150,000. Under CDBG regulations, the HIP is eligible to
Diamond Bar 2013-2021 Housing Element III. Resources and Opportunities
III-2 January 2014
receive unexpended CDBG funds from the previous fiscal year that are reallocated by
the Los Angeles County Community Development Commission. An additional $50,000
from the 2012-2013 fiscal year is anticipated for reallocation to the 2013-2014 fiscal year
bringing the total allocation for the HIP to $200,000. From 2009 to the current fiscal year, a
total of 1 very-low-, 13 low-, and 15 moderate-income households have participated in
the HIP. Each household that qualifies for the HIP program is eligible to receive up to
$17,000 from a combination of no-interest loans and grants. The City actively promotes
the program and consistently exhausts its funding allocation each year.
Since Program Year 2011-2012, the allocation of the Community Development Block
Grant has been reduced by an average of 18% each program year, and an additional
5% reduction is anticipated for FY2014-2015. Therefore, the City anticipates receiving
approximately $202,000 per year in CDBG funds from the County during the current
planning period.
Section 8 Rental Assistance – The City of Diamond Bar cooperates with the
Housing Authority of the County of Los Angeles (HACoLA), which administers the Section
8 Voucher Program. The Section 8 program provides rental assistance to low-income
persons in need of affordable housing. There are two types of subsidies under Section 8:
certificates and vouchers. A certificate pays the difference between the fair market rent
and 30% of the tenant’s monthly income, while a voucher allows a tenant to choose
housing that may cost above the fair market figure, with the tenant paying the extra
cost. The voucher also allows the tenant to rent a unit below the fair market rent figure
with the tenant keeping the savings.
Low-Income Housing Tax Credit Program - The Low-Income Housing Tax Credit
Program was created by the Tax Reform Act of 1986 to provide an alternate method of
funding low-and moderate-income housing. Each state receives a tax credit, based
upon population, toward funding housing that meets program guidelines. The tax credits
are then used to leverage private capital into new construction or acquisition and
rehabilitation of affordable housing. Limitations on projects funded under the Tax Credit
programs include minimum requirements that a certain percentage of units remain rent -
restricted, based upon median income, for a term of 15 years.
2. Local Resources
Tax Exempt Multi-Family Revenue Bonds – The construction, acquisition, and
rehabilitation of multi-family rental housing developments can be funded by tax exempt
bonds which provide a lower interest rate than is available through conventional
financing. Projects financed through these bonds are required to set aside 20 % of the
units for occupancy by very low-income households or 40% of the units to be set aside for
households at 60% of the area median income (AMI). Tax exempt bonds for multi-family
housing may also be issued to refinance existing tax exempt debt, which is referred to as
a refunding bond issue.
The Seasons Diamond Bar Senior Apartments was refinanced in 1999 under the California
Community Development Authority’s Multifamily Housing Re-funding Bond. According to
the terms of the new bond agreement, income restrictions for residents and
corresponding rent limits were set. For the duration of the bond which expires in
Diamond Bar 2013-2021 Housing Element III. Resources and Opportunities
III-3 January 2014
December of 2034, all units will be affordable: 30 units will be very low income at 50%
AMI, 82 units will be low income at 80% AMI, and 37 units will be moderate income at
100% AMI. The Seasons Apartments are owned by the Corporate Fund for Housing, a
non-profit organization.
Housing Agreements – The City can assist in the development of new affordable
housing units by entering into Disposition Development Agreements (DDA) or Owner
Participation Agreements (OPA) with developers. DDAs or OPAs may provide for the
disposition of Agency-owned land at a price which can support the development of
units at an affordable housing cost for low- and moderate-income households. These
agreements may also provide for development assistance, usually in the form of a
density bonus or the payment of specified development fees or other development
costs which cannot be supported by the proposed development.
Mortgage Credit Certificates – The Mortgage Credit Certificates (MCC) program is
designed to help low- and moderate-income first-time homebuyers qualify for
conventional first mortgage loans by increasing the homebuyer’s after-tax income. The
MCC is a direct tax credit for eligible homebuyers equal to 20% of the mortgage interest
paid during the year. The other 80% of mortgage interest can still be taken as an income
deduction. Diamond Bar is a participating city in the County-run MCC program. The
maximum gross annual income limits in order to be eligible for the MCC program is
currently (2013) $99,360 for one- to two-person households and $115,920 for households
of three or more.
Home Ownership Program – The Home Ownership Program (HOP) provides
assistance to low-income, first-time homebuyers in purchasing a home. It is administered
by the County of Los Angeles Community Development Commission’s Housing
Development and Preservation Division. The program has provided hundreds of Los
Angeles County residents with the means to afford to fulfill their dream of home
ownership. The maximum gross annual income for eligible participants is 80% of the
median income for Los Angeles County.
Southern California Home Financing Authority Programs – SCHFA is a joint powers
authority between Los Angeles and Orange Counties formed in June 1988 to issue tax -
exempt mortgage revenue bonds for low- to moderate-income First-Time Homebuyers.
For almost 25 years, SCHFA has helped thousands of individuals and families fulfill their
dreams of owning a home. This program makes buying a home more affordable for
qualifying homebuyers by offering a competitive 30-year fixed rate loan and a grant for
downpayment and closing costs assistance. The program is administered by the Los
Angeles County Community Development Commission (CDC) and the Public Finance
Division of the County of Orange. SCHFA does not lend money directly to homebuyers.
Homebuyers must work directly with a participating lender. Income limits for Los Angeles
County as of 2013 are $99,360 for households with 1 or 2 persons and $111,515 for
households of 3 or more.
Fannie Mae Down Payment Assistance Program – The Federal National Mortgage
Association, better known as “Fannie Mae,” offers a program that provides second
mortgages to homeowners. The second mortgage can serve as the down payment and
closing costs on home purchases. Under this program, a city or county is required to post
Diamond Bar 2013-2021 Housing Element III. Resources and Opportunities
III-4 January 2014
a reserve fund equal to 20% of an amount that Fannie Mae then makes available for
such mortgages.
Non-Profit Organizations – Non-profit organizations play a major role in the
development of affordable housing in Los Angeles County. The Community
Development Commission of Los Angeles County supplements its own efforts of
producing affordable housing by entering into partnerships with private sector and non-
profit developers and housing development corporations.
C. Energy Conservation Opportunities
As residential energy costs rise, the subsequent increasing utility costs reduce the
affordability of housing. Although the City is mostly developed, new infill development
and rehabilitation activities could occur, allowing the City to directly affect energy use
within its jurisdiction.
State of California Energy Efficiency Standards for Residential and Nonresidential
Buildings were established in 1978 in response to a legislative mandate to reduce
California's energy consumption. The standards are codified in Title 24 of the California
Code of Regulations and are updated periodically to allow consideration and possible
incorporation of new energy efficiency technologies and methods. California's building
efficiency standards (along with those for energy efficient appliances) have saved more
than $56 billion in electricity and natural gas costs since 1978. It is estimated the
standards will save an additional $23 billion by 20138.
Title 24 sets forth mandatory energy standards and requires the adoption of an “energy
budget” for all new residential buildings and additions to residential buildings. Separate
requirements are adopted for “low-rise” residential construction (i.e., no more than three
stories) and non-residential buildings, which includes hotels, motels, and multi -family
residential buildings with four or more habitable stories. The standards specify energy
saving design for lighting, walls, ceilings and floor installations, as well as heating and
cooling equipment and systems, gas cooling devices, conservation standards and the
use of non-depleting energy sources, such as solar energy or wind power. The home
building industry must comply with these standards while localities are responsible for
enforcing the energy conservation regulations through the plan check and building
inspection processes.
In addition to state energy regulations, the City encourages energy efficiency through its
participation in the Single-Family Rehabilitation Program, which provides low- and
moderate-income households funds for home improvements that may include insulation
and energy-efficient windows and doors. The City also encourages mixed-use
development, which facilitates energy efficiency by reducing vehicular trip lengths.
Program 10 in the Housing Action Plan (Chapter V) describes how the City intends to
pursue mixed-use development in the Tres Hermanos property, one of the largest
remaining undeveloped areas in the city. Recycling is another area where the City
encourages energy conservation. Each year the City publishes and distributes the Enviro-
8 California Energy Commission (http://www.energy.ca.gov/title24)
Diamond Bar 2013-2021 Housing Element III. Resources and Opportunities
III-5 January 2014
Link newsletter, which informs residents on opportunities for recycle and minimize waste.
The city also maintains this information on its web page at http://www.ci.diamond-
bar.ca.us/Index.aspx?page=725.
Diamond Bar 2013-2021 Housing Element III. Resources and Opportunities
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Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-1 January 2014
IV. CONSTRAINTS
In planning for the provision of housing, constraints to the development, maintenance
and improvement of housing must be recognized, and jurisdictions must take
appropriate steps to mitigate them where feasible. Local government cannot control
many of these constraints, such as those related to general economic and market
conditions, but others can be addressed. Potential constraints to housing are discussed
below, and include governmental and non-governmental constraints.
A. Governmental Constraints
Governmental regulations, while intentionally controlling the quality of development in
the community can also unintentionally increase the cost of development and thus the
cost of housing. These governmental constraints include land use controls, building codes
and their enforcement, site improvements, fees and other exactions required of
developers, and local development processing and permit procedures.
Land use controls may limit the amount or density of development, thus increasing the
cost per unit. On-site and off-site improvements such as roads, traffic signals on adjacent
streets, or sewer systems may increase an individual project’s costs of development.
Processing and permit requirements may delay construction, increasing financing and/or
overhead costs of a development. The following section describes potential govern-
mental constraints, which may affect the supply and cost of housing in Diamond Bar.
1. Land Use Plans and Regulations
General Plan
Each city and county in California must prepare a comprehensive, long-term General
Plan to guide its future. The land use element of the General Plan establishes the basic
land uses and density of development within the various areas of the City. Under state
law, the General Plan elements must be internally consistent and the City’s zoning must
be consistent with the General Plan. Thus, the land use plan must provide suitable
locations and densities to implement the policies of the Housing Element.
The Diamond Bar General Plan Land Use Element provides for six residential land use
designations, as shown in Table IV-1.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-2 January 2014
Table IV-1
Residential Land Use Categories –
Diamond Bar General Plan
Designation
Maximum
Density* Description
Rural Residential (RR) 1.0 Single family detached units on large lots, generally in hillside areas.
Low Density Residential (RL) 3.0 Single-family detached homes on large to moderate sized lots.
Low Medium Density Residential (RLM) 5.0 Single-family detached homes on moderate to small-sized lots.
Medium Density Residential (RM) 12.0 Townhomes, condominiums, apartments, mobile homes, and other
multifamily residential projects.
Medium High Residential (RMH) 16.0 Townhomes, condominiums, apartments, other multifamily residential
projects, and mobile home parks.
High Density Residential (RH) 20.0 High density condominium and apartment projects, other high density
residential projects, and mobile home parks.
High Density Residential-30 (RH-30) 30.0 High density condominium and apartment projects.
Source: City of Diamond Bar General Plan, 2013.
* Density expressed in dwelling units per gross acre.
The majority of the land area within the City is developed or is designated for residential
use. The Land Use Element of the Diamond Bar General Plan designates approximately
5,824 acres (61%) of the City’s total land inventory for residential uses, providing for a
range of residential types and densities throughout the City.
In order to provide adequate sites commensurate with the RHNA allocation, the City in
2013 amended the General Plan to establish a new RH-30 land use category allowing
multi-family residential development with a maximum density of 30 units per acre (see
also Appendix B).
Planning Areas and Specific Plans
In addition to the seven residential land use districts, the Land Use Element provides for
residential uses within the Specific Plan and Planning Area classifications. Development
within areas designated Specific Plan or Planning Area are processed through use of a
master plan or specific plan, a planned unit development, or similar mechanism, and
development intensities must be consistent with those specified in the General Plan.
Specific Plan and Planning Area projects must provide a greater level of community
amenities and cohesiveness, achieve superior design, and create a more desirable living
environment than could be achieved through conventional subdivision design and
requirements. The Land Use Element identifies four mixed-use Planning Areas within the
City of Diamond Bar, two of which are intended to contain residential uses: PA 1, which
encompasses approximately 720 acres and is intended for agricultural uses, low-density
residential uses at a density of one dwelling unit per five acres, high-density multi-family
residential uses at up to 30 units per acre, commercial uses not typical of the area, and
education/institutional uses; PA 2, which encompasses approximately 400 acres and
allows for a maximum of 130 single-family detached units and open space. PA 3, which
encompasses approximately 55 acres and allows for 200 units with a mix of single-family
detached homes and condominiums, commercial, religious assembly and open space;
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-3 January 2014
and PA 4, which encompasses approximately 82 acres and is intended for 99 single-
family homes and open space.
Zoning Designations
The City regulates the type, location, density, and scale of residential development
through the Zoning Ordinance and Zoning Map. Zoning regulations serve to implement
the General Plan and are designed to protect and promote the health, safety, and
general welfare of residents. The Zoning Ordinance also helps to preserve the character
and integrity of existing neighborhoods. The Zoning Ordinance and Zoning Map set forth
residential development standards for each zoning district.
The seven zoning districts that allow residential units as a permitted use are as follows:
RR Rural Residential
RL Low Density Residential
RLM Low Medium Density Residential
RM Medium Density Residential
RMH Medium High Density Residential
RH High Density District
RH-30 High Density District (30 units per acre)
A summary of the development standards for the seven major zoning districts permitting
residential development is provided in Table IV-2. These development standards are
reasonably necessary to protect the public health, safety and welfare, maintain quality
of life, and are not considered to be constraints to the development of housing.
Table IV-2
Residential Development Standards
Development Standard1
Zoning District Designations
RR RL RLM RM RMH RH/RH-30
Minimum Lot Area (sq. ft.) 1 acre 10,000 sf 8,000 sf 5,000 sf 5,000 sf 5,000 sf
Minimum Front Yard (ft.) 30 ft 20 ft 20 ft 20 ft 20 ft 20 ft
Minimum Side Yard (ft.)
15 ft. on one
side, and 10 ft.
on the other2
10 ft. on one
side, and 5 ft.
on the other3
10 ft. on one
side, and 5 ft.
on the other3
5 ft. 5 ft.
5 ft. plus 1 ft. for
each story over
2
Minimum Street Side Setback (ft.)
15 ft., reversed
corner lot; 10 ft.
otherwise
10 ft., reversed
corner lot; 5 ft.
otherwise
10 ft., reversed
corner lot; 5 ft.
otherwise
10 ft., reversed
corner lot; 5 ft.
otherwise
7.5 ft., reversed
corner lot; 5 ft.
otherwise
7.5 ft., reversed
corner lot; 5 ft.
otherwise
Minimum Rear Yard (ft.) 25 ft.4 20 ft.4 20 ft.4 25 ft.4 20 ft.4 20 ft.4
Maximum Lot Coverage (%) 30% 40% 40% 30% 30% 30%
Maximum Building Height (ft.) 35 ft 35 ft 35 ft 35 ft 35 ft 35 ft
Source: Diamond Bar Zoning Ordinance
Notes:
1. Development standards in the planned communities are governed by a master plan, specific plan, or similar document and may vary from current zoning.
2. There cannot be less than 25 ft. between structures on adjoining parcels.
3. There cannot be less than 15 ft. between structures on adjoining parcels.
4. From the property line or building pad on a descending slope, whichever is applicable.
A summary of the types of housing permitted by the City’s Zoning Ordinance is provided
in Table IV-3.
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IV-4 January 2014
Table IV-3
Permitted Residential Development by Zoning District
Housing Type RR RL RLM RM RMH RH/RH-30
Single-Family Detached P P P P P P
Single-Family Attached P P P
Multi-Family P P P
Manufactured Housing P P P P P P
Mobile Home Park CUP CUP CUP CUP CUP CUP
Second Units P P
Emergency Shelters1
Transitional & Supportive Housing 2 2 2 2 2 2
Residential Care Home (6 or fewer persons)3 P P P P P P
Residential Care Home (7 or more persons)3 CUP CUP CUP
Senior Housing P P P P P P
Single Room Occupancy4
Source: Diamond Bar Zoning Ordinance P = Permitted, ministerial zoning clearance required CUP = Conditional Use Permit
Notes:
1. Emergency shelters are permitted in the Light Industrial zone.
2. Transitional and supportive housing are permitted in any residential zone subject to the same standards and procedures as apply to other residential uses of
the same type in the same zone.
3. Residential Care Homes are defined as facilities providing residential social and personal care for children, the elderly, and people with some limits on their
ability for self-care, but where medical care is not a major element. Includes children's' homes; family care homes; foster homes; group homes; halfway
houses; orphanages; rehabilitation centers; and similar uses.
4. SROs are conditionally permitted in the I (light industrial) zone
The Zoning Ordinance provides for a variety of housing types including single-family
homes (both attached and detached), multi-family (both rental and condominiums),
manufactured housing, special needs housing, and second units. Affordable housing
can be accommodated in all residential districts.
Effect of Zoning and Development Standards on Housing Supply and
Affordability
Zoning regulations and development standards can affect the feasibility of development
projects, particularly housing that is affordable to lower- and moderate-income
households. The most significant of these standards is density. Higher densities generally
result in lower per-unit land costs, thereby reducing overall development cost, although
this is not always the case. For example, at some point higher density may require more
expensive construction methods such as parking in structures or below-grade garages.
Pursuant to AB 2348 of 2004, the “default density” for Diamond Bar is 30 dwelling units per
acre9. The default density refers to the density at which lower-income housing
development is presumed to be feasible, although state law allows jurisdictions to
propose alternative densities that are sufficient to facilitate affordable housing based on
local experience and circumstances. During the 4th planning cycle the City amended
the Development Code to establish the RH-30 district, which allows multi-family
development at the default density of 30 units per acre. Although appropriate zoning
regulations are necessary for affordable housing to be feasible, it should be recognized
9 Memo of June 9, 2005 from California Department of Housing and Community Development on AB 2348
of 2004.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-5 January 2014
that public subsidies are also necessary to reduce costs to the level that lower-income
households can afford.
Special Needs Housing
Persons with special needs include those in residential care facilities, persons with
disabilities, the elderly, farm workers, persons needing emergency shelter or transitional
living arrangements, and single room occupancy units. The City’s provisions for these
housing types are discussed below.
Residential Care Facilities
Residential care facilities refer to any family home, group home, or rehabilitation facility
that provides non-medical care to persons in need of personal services, protection,
supervision, assistance, guidance, or training essential for daily living. The Development
Code explicitly references Residential Care Homes (Section 22.80.020). In accordance
with state law, residential care homes that serve six or fewer persons are permitted by -
right in all residential districts with only a ministerial zoning clearance required. Residential
care homes serving more than six persons are permitted by conditional use permit in the
RM, RMH, and RH Districts. There is no definition of “family” nor are there any separation
requirements for residential care facilities in the Development Code. These provisions are
consistent with state law and do not pose a significant constraint on the establishment of
such facilities.
Housing for Persons with Disabilities
Both the federal Fair Housing Act and the California Fair Employment and Housing Act
impose an affirmative duty on local governments to make reasonable accommodations
(i.e. modifications or exceptions) in their zoning laws and other land use regulations when
such accommodations may be necessary to afford disabled persons an equal
opportunity to use and enjoy a dwelling. The Building Codes adopted by the City of
Diamond Bar incorporate accessibility standards contained in Title 24 of the California
Administrative Code. For example, apartment complexes of three or more units and
condominium complexes of four or more units must be designed to accessibility
standards.
Compliance with building codes and the ADA may increase the cost of housing
production and can also impact the viability of rehabilitation of older properties required
to be brought up to current code standards. However, these regulations provide
minimum standards that must be complied with in order to ensure the development of
safe and accessible housing.
Senate Bill 520 of 2001 requires cities to make reasonable accommodation in housing for
persons with disabilities. The City has adopted procedures (Development Code
§22.02.060) for reviewing and approving requests for reasonable accommodation for
persons with disabilities consistent with state law.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-6 January 2014
Farm Worker Housing
As discussed in Chapter II. Housing Needs Assessment, the City of Diamond Bar does not
have major agricultural areas and has no significant need for permanent on-site farm
worker housing. The City’s overall efforts to provide and maintain affordable housing
opportunities will help to support the few seasonal farm workers that may choose to
reside in the City.
Housing for the Elderly
Senior housing projects are a permitted use in all residential Districts. A density bonus is
also permitted for the construction of senior housing pursuant to Government Code
§§65915-65918. The zoning ordinance is not considered to be a constraint to the
development of senior housing because the regulations are the same as for other
residential uses in the same districts.
Emergency Shelters and Transitional/Supportive Housing
Emergency shelters are facilities that provide a safe alternative to the streets either in a
shelter facility, or through the use of motel vouchers. Emergency shelter is short-term and
usually for 30 days or less. Transitional housing is longer-term, typically up to two years,
while supportive housing may have no occupancy limit. Programs that operate
transitional and supportive housing generally require that the resident participate in a
structured program to work toward established goals so that they can move on to
permanent housing and may include supportive services such as counseling.
SB 2 of 2007 strengthened the planning requirements for emergency shelters and
transitional/supportive housing. This bill requires jurisdictions to evaluate their need for
shelters compared to available facilities to address the need. If existing shelter facilities
are not sufficient to accommodate the need, jurisdictions must designate at least one
zone where year-round shelters can be accommodated. There are currently no
emergency shelters located in the City. However, there are no known homeless persons
living in Diamond Bar, therefore no need for shelters presently exists.
In order to reduce constraints to the establishment of emergency shelters, the
Development Code was amended to allow shelters with up to 30 beds by-right in the
Light Industrial (I) zone subject to objective development standards. This zone
encompasses approximately 98 acres with an average parcel size of 1.6 acres and
contains underutilized parcels and vacant buildings that could accommodate at least
one emergency shelter.
During the 4th planning period the San Gabriel Valley Council of Governments initiated a
study to assess the needs of the homeless and develop a coordinated strategy to
address those needs. As a member jurisdiction, Diamond Bar is cooperating in this study
and is committed to a fair-share approach to providing the necessary services and
facilities for the homeless persons and families identified in the community.
SB 2 also requires that transitional and supportive housing be considered a residential use
that is subject only to the same requirements and procedures as other residential uses of
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-7 January 2014
the same type in the same zone. In 2013 the Development Code was amended in
compliance with SB 2.
Single Room Occupancy
Single room occupancy facilities are small studio-type units and are conditionally
permitted in the Light Industrial District. Development standards for these uses are no
more restrictive than for other uses allowed in this district.
Off-Street Parking Requirements
The City’s parking requirements for residential uses vary by residential type. Single-family
dwellings and duplex housing require two parking spaces per unit in a garage. Mobile
homes require two parking spaces plus guest parking. Studio units require one space for
each unit in a garage, plus guest parking. Multi-family dwellings, condos, and other
attached dwellings are required to have two spaces in a garage for each unit plus 0.5
space for each bedroom over two, and guest parking. Second units are required to
have one space in addition to that required for the single-family unit. Senior housing
projects are required to provide one space for each unit with half of the spaces
covered, plus one guest parking space for each ten units. Senior congregate care
facilities are required to have 0.5 space for each residential unit, plus one space for each
four units for guests and employees. Extended care facilities are required to provide one
space for each three beds the facility is licensed to accommodate. These parking
requirements are summarized in Table IV-4.
The required parking is not excessive and is not considered to be a constraint on the
production of affordable housing. However, in order to facilitate affordable housing
production, the Development Code was amended in the 4th planning cycle to reduce
the parking requirement and allow parking for lower-income apartments to be provided
in carports rather than garages.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-8 January 2014
Table IV-4
Residential Parking Requirements
Type of Unit Minimum Parking Space Required
Single Family Detached Dwellings 2 off-street parking spaces per dwelling (in a garage)
Duplex Housing Units 2 off-street parking spaces for each unit (in a garage)
Mobile Homes (in M.H. parks) 2 off-street parking spaces for each mobile home (tandem parking allowed in an
attached carport), plus guest parking*
Secondary Residential Units 1 off-street parking space in addition to that required for a single-family unit
Multi-Family Dwellings, Condominiums, and Other Attached Dwellings*
Studio 1.0 off-street parking space per dwelling unit (in a garage), plus guest parking*
1 or More Bedrooms 2.0 off-street parking spaces per unit (in a garage), plus 0.5 additional spaces for each
bedroom over 2, plus guest parking**
Senior Housing Projects 1 off-street parking space per unit with half of the spaces covered, plus 1 guest parking
space for each 10 units
Senior Congregate Care Facilities 0.5 space for each residential unit, plus 1 space for each 4 units for guests and
employees
Extended Care Facilities (elderly, skilled
nursing facilities and residential care homes)
1 space for each 3 beds the facility is licensed to accommodate
*Reduced parking is allowed for projects that provide affordable housing pursuant to state Density Bonus law.
** Guest parking shall be provided at a ratio of one space for each four required parking spaces.
Source: Diamond Bar Zoning Ordinance
Second Units
In response to state-mandated requirements and local needs, the City of Diamond Bar
allows for the development of accessory or second dwelling units by right in the RR and
RL Districts. Second units are allowed on lots which have a minimum of 10,000 gross
square feet and a minimum buildable pad area of 8,000 square feet, a minimum width
of 50 feet and a minimum depth of 100 feet. A second unit shall not exceed 600 gross
square feet in floor area if the parcel is between 10,000 and 20,000 square feet and shall
not exceed 1,200 square feet in gross floor area if the parcel is over 20,000 gross square
feet with a minimum building pad area of 10,000 square feet. Second units must contain
separate kitchen and bathroom facilities and have a separate entrance from the
primary residence. In addition, second units may not contain more than two bedrooms.
Second units serve to augment resources for senior housing, or other low- and moderate-
income segments of the population. The development standards are reasonable to
ensure neighborhood compatibility, and do not present an unreasonable constraint to
development.
Density Bonus
Under Government Code Section 65915-65918, a density increase of up to 35% over the
otherwise maximum allowable residential density under the Municipal Code is available
to developers who agree to construct housing developments with units affordable to
low- or moderate-income households. A senior housing development is eligible for a 20%
density bonus if it includes at least 35 dwelling units, and the applicant seeks a density
bonus. The Development Code has been amended to reflect the provisions of SB 1818.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-9 January 2014
Mobile Homes/Manufactured Housing
There is often an economy of scale in manufacturing homes in a plant rather than on
site, thereby reducing cost. State law precludes local governments from prohibiting the
installation of mobile homes on permanent foundations on single-family lots. It also
declares a mobile home park to be a permitted land use on any land planned and
zoned for residential use, and prohibits requiring the average density in a new mobile
home park to be less than that permitted by the Municipal Code.
In the City of Diamond Bar, manufactured housing is allowed in all residential zones as a
permitted use provided the installation complies with the site development standards for
the applicable zoning district. Mobile home parks are allowed as conditional use within
all residential districts. There are two mobile home parks in Diamond Bar, both located in
the western portion of the City: Diamond Bar Estates and Walnut Creek Estates.
Condominium Conversions
In order to reduce the impacts of condominium conversions on residents of rental
housing, some of which provides housing for low- and moderate-income persons, the
City’s Municipal Code requires that in addition to complying with all of the regulations
and noticing requirements of the Subdivision Map Act for condo conversions, the
applicant must propose a relocation assistance program that will assist tenants displaced
through the conversion in relocating to equivalent or better housing, assess the vacancy
rate in multi-family housing within the City, and provide a report to all tenants of the
subject property at least three days prior to the hearing.
When a condo conversion is permitted, the increase in the supply of less expensive for-
sale units helps to compensate for the loss of rental units. The ordinance to regulate
condominium conversions is reasonable to preserve rental housing opportunities, and does
not present an unreasonable constraint on the production of ownership housing.
Building Codes
State law prohibits the imposition of building standards that are not necessitated by local
geographic, climatic or topographic conditions and requires that local governments
making changes or modifications in building standards must report such changes to the
Department of Housing and Community Development and file an expressed finding that
the change is needed.
The City's building codes are based upon the California Building, Plumbing, Mechanical
and Electrical Codes. These are considered to be the minimum necessary to protect the
public's health, safety and welfare. No additional regulations have been imposed by the
City that would unnecessarily add to housing costs.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-10 January 2014
2. Development Processing Procedures
Residential Permit Processing
State Planning and Zoning Law provides permit processing requirements for residential
development. Within the framework of state requirements, the City has structured its
development review process in order to minimize the time required to obtain permits
while ensuring that projects receive careful review. All residential development is
reviewed by City staff for zoning, building, and fire code compliance prior to issuance of
building permits.
Processing times vary and depend on the size and complexity of the project. Projects
reviewed by the Planning Commission, such as Conditional Use Permits, typically require
between 1 to 2 months to process. Tentative parcel maps and tentative tract maps
typically require 3 to 6 months to process. Projects reviewed by the City Council, such as
General Plan and Zoning Amendments, typically require between 3 to 6months to
process.
Table IV-5 identifies the review authority responsible for making decisions on land use
permits and other entitlements, as well as the estimated processing time for each type of
application.
Table IV-5
Review Authority for Residential Development
Type of Permit or Decision (*)
Est. Processing
Time Director
Hearing
Officer
Planning
Commission
City
Council
Administrative Development Review (SF or MF) 6-8 weeks Final Appeal Appeal
Development Review (SF or MF) 8 weeks Final Appeal
Development Agreement** 12-24 weeks Recommend Final
Minor Conditional Use Permit 4-6 weeks Final Appeal Appeal
Conditional Use Permit 8 weeks Final Appeal
Minor Variance 2-4 weeks Final Appeal Appeal
Variance** 4-8 weeks Final Appeal
General Plan Amendment** 12-24 weeks Recommend Final
Specific Plan** 12-24 weeks Recommend Final
Zoning Map or Development Code Amendment 12-24 weeks Recommend Final
Tentative Map 12-24 weeks Recommend Final
Plot Plan 4 weeks Final Appeal Appeal
Zoning Clearance (over the counter) 1 week Final Appeal Appeal
Source: Diamond Bar Development Code; Community Development Department
Notes:
* The Director and Hearing Officer may defer action on permit applications and refer the item(s) to the Commission for final decision.
** Permit typically involves environmental clearance pursuant to CEQA and is subject to the Permit Streamlining Act.
Certain steps of the development process are required by State rather than local laws.
The state has defined processing deadlines to limit the amount of time needed for review
of required reports and projects. The following describes the five-step development
review process in Diamond Bar:
Application Submittal. Applications for land use permits and other matters
pertaining to the Development Code must be filed on a City application form,
together with all necessary fees and/or deposits, exhibits, maps, materials,
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-11 January 2014
plans, reports, and other information required by the Development Services
Department. Prior to submitting an application, applicants are strongly
encouraged to request a pre-application conference with staff. The purpose
of the pre-application conference is to inform the applicant of City
requirements as they pertain to the proposed development project, review
the procedures outlined in the Development Code, explore possible
alternatives or modifications, and identify necessary technical studies and
required information related to the environmental review of the project.
Single-family residential uses are permitted by-right in all residential zoning
districts. Multi-family residential uses are permitted by-right in the RM, RMH and
RH zones. All new residential construction and some additions to existing
residences are subject to “Development Review.”
Development Review and Administrative Development Review applications
for projects that also require the approval of another discretionary permit (e.g.
conditional use permit) shall be acted upon concurrently with the
discretionary permit and the final determination shall be made by the highest
level of review authority in compliance with Table IV-5.
Development Review. An application for Development Review is required for
residential projects that propose one or more dwelling units (detached or
attached) and that involve the issuance of a building permit for construction
or reconstruction of a structure(s) meeting the following criteria:
New construction on a vacant lot and new structures, additions to
structures, and reconstruction projects which are equal to 50% or greater
of the floor area of existing structures on site, or have 5,001 square feet or
more of combined gross floor area in any commercial, industrial, and
institutional development; or
Projects involving a substantial change or intensification of land use (e.g.
the conversion of and existing structure to a restaurant, or the conversion
of a residential structure to an office or commercial use); or
Residential, commercial, industrial, or institutional projects proposed upon
a descending slope abutting a public street.
Administrative Development Review. An application for Administrative
Development Review is required for residential, industrial, and institutional
developments that involve the issuance of a building permit for construction or
reconstruction of a structure(s) meeting the following thresholds of review:
Commercial, industrial, and institutional developments that propose up to
5,000 square feet of combined floor area; or
Projects that do not meet the specific criteria for Development Review.
Development Review and Administrative Development Review are non-
discretionary review procedures intended to address design issues such as
landscaping and building massing, and do not include a review of the merits
or suitability of the use itself.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-12 January 2014
Initial Application Review. The Director reviews all applications for complete-
ness and accuracy before they are accepted as being complete and
officially filed. Processing of applications does not commence until all required
fees and deposits have been paid. Without the application fee or a deposit,
the application is not deemed complete.
Within 30 days of a submittal, staff reviews the application package and the
applicant is informed in writing of whether or not the application is deemed
complete and has been accepted for processing. If the application is
incomplete, the applicant is advised regarding what additional information is
required.
If a pending application is not deemed complete within six months after the
first filing with the Department, the application expires and is deemed
withdrawn. Any remaining deposit amount is refunded, subject to
administrative processing fees.
Environmental Review. After acceptance of a complete application, a
project is reviewed for compliance with the California Environmental Quality
Act (CEQA). A determination is made regarding whether or not the proposed
project is exempt from the requirements of CEQA. If the project is not exempt,
a determination is made regarding whether a Negative Declaration,
Mitigated Negative Declaration, or Environmental Impact Report will be
required based on the evaluation and consideration of information provided
by an initial study. If an EIR is required, a minimum of nine months to one year is
typically required to complete the process.
Staff Report and Recommendations. A staff report is prepared by the Director
that describes the conclusions and findings about the proposed land use
development. The report includes recommendations on the approval,
approval with conditions, or disapproval of the application. Staff reports are
provided to the applicant at the same time they are provided to the Hearing
Officer, or members of the Commission and/or Council, before a hearing on
the application.
Notice and Hearings. An application for a development review or
administrative development review is scheduled for a public hearing once the
department has determined the application complete. Administrative
development reviews and minor CUPs are heard by a Hearing Officer (staff)
while more significant applications are heard by the Planning Commission.
Legislative acts such as General Plan amendments, zone changes, specific
plans and development agreements require City Council approval. Upon
completion of the public hearing, the review authority shall announce and
record the decision within 21 days following the conclusion of the public
hearing. The decision shall contain the required findings and a copy of the
resolution shall be mailed to the applicant.
These processes are typical of most California jurisdictions and help to ensure that the
development review process does not act as a constraint to housing development.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-13 January 2014
3. Development Fees and Improvement Requirements
After the passage of Proposition 13 and its limitation on local governments’ property tax
revenues, cities and counties have faced increasing difficulty in providing public services
and facilities to serve their residents. One of the main consequences of Proposition 13 has
been the shift in funding of new infrastructure from general tax revenues to development
impact fees and improvement requirements on land developers. The City requires
developers to provide on-site and off-site improvements necessary to serve their projects.
Such improvements may include water, sewer and other utility extensions, street
construction and traffic control device installation that are reasonably related to the
project. Dedication of land or in-lieu fees may also be required of a project for rights-of-
way, transit facilities, recreational facilities and school sites, consistent with the Subdivision
Map Act.
Table IV-6
Planning and Development Fees
Fee Category Fee or Deposit Amounta
Planning and Application Fees
Administrative Development Review $1,408.91deposit
Development Agreement $4,226.73deposit
General Plan Amendment $5,704.57deposit
Specific Plan $5,635.64deposit
Conditional Use Permit $2,817.82deposit
Minor Conditional Use Permit $1,408.91deposit
Tentative Tract Map $7,044.55deposit
Tentative Parcel Map $4,226.73 deposit
Environmental
Environmental Analysis Actual cost
Environmental Mitigation Monitoring Program b
Engineering and Public Works
See Appendix D
Development Impact Fees SF MF
Drainage Facilities None
Traffic Facilities $900
Public Facilities None
Fire Facilities None
Park Facilities $2,175
Sewer Connection $2,410 $1,446
Total impact fees per unit $5,485 $4,521
Source: City of Diamond Bar, 2013
a Items with deposits are based on actual processing costs which may exceed initial deposit amount.
b Cost determined as part of the environmental review
State law limits fees charged for development permit processing to the reasonable cost
of providing the service for which the fee is charged. Various fees and assessments are
charged by the City and other public agencies to cover the costs of processing permit
applications and providing services and facilities such as schools, parks and
infrastructure. Table IV-6 provides a list of fees the City of Diamond Bar charges for new,
standard residential development. The City periodically evaluates the actual cost of
processing development permits when revising its fee schedule. The last fee schedule
update was adopted in 2012.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-14 January 2014
Improvement Requirements
Throughout California, developers are required to construct on- and off-site
improvements needed to serve new projects, including streets, sidewalks, and utilities.
City road standards vary by roadway designation as provided in Table IV-7.
A local residential street requires a 44- to 60-foot right-of-way, with two 12-foot travel
lanes. These road standards are typical for cities in Los Angeles County and do not act as
a constraint to housing development.
The City’s Capital Improvement Program (CIP) contains a schedule of public improve-
ments including streets, bridges, overpasses and other public works projects to facilitate
the continued build-out of the City’s General Plan. The CIP helps to ensure that
construction of public improvements is coordinated with private development.
Table IV-7
Road Improvement Standards
Roadway Designation Number of Lanes Right-of-Way Width Curb-to Curb Width
Major arterial 4-6 100-120 N/A
Secondary arterial 4 60-100 N/A
Collector street 2-4 60-80 N/A
Local street 2 44-60 28-36
Source: City of Diamond Bar, 2013
Although development fees and improvement requirements increase the cost of
housing, cities have little choice in establishing such requirements due to the limitations
on property taxes and other revenue sources needed to fund public services and
improvements.
B. Non-Governmental Constraints
1. Environmental Constraints
Environmental constraints include physical features such as steep slopes, fault zones,
floodplains, sensitive biological habitat, and agricultural lands. In many cases,
development of these areas is constrained by state and federal laws (e.g., FEMA
floodplain regulations, the Clean Water Act and the Endangered Species Act, and the
state Fish and Game Code and Alquist-Priolo Act).
Most of the level, easily developable land in Diamond Bar has already been developed,
and much of the remaining land has a variety of geotechnical and topographic
conditions that may constrain the development of lower-priced residential units. Large
portions of the City contain steep slopes that pose a significant constraint to
development.
In addition to slope constraints, many of the hillsides in Diamond Bar have a potential for
landslides. Slope stability is affected by such factors as soil type, gradient of the slope,
underlying geologic structure, and local drainage patterns. The rolling topography and
composition of local soils throughout Diamond Bar create numerous areas for potential
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-15 January 2014
landslide hazards. Although many historical landslide locations have been stabilized,
there still exist a number of potential landslide areas in the eastern portion of the City as
well as within Tonner Canyon in the Sphere of Influence. Figure IV-1 illustrates the
significant areas with environmental constraints.
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-16 January 2014
Figure IV-1
Environmental Constraints
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-17 January 2014
2. Infrastructure Constraints
As discussed under Development Fees and Improvement Requirements, the City requires
developers to provide on-site and off-site improvements necessary to serve their projects.
Dedication of land or in-lieu fees may also be required of a project for rights-of-way,
transit facilities, recreational facilities and school sites, consistent with the Subdivision Map
Act.
Additionally, the City’s Capital Improvement Program (CIP) contains a schedule of public
improvements including streets and other public works projects to facilitate the
continued build-out of the City’s General Plan. The CIP helps to ensure that construction
of public improvements is coordinated with development. As a result of these policies,
any infrastructure constraints which currently exist must be fully mitigated and financed
as growth occurs.
Wastewater
Wastewater conveyance and treatment in Diamond Bar is provided by the County of
Los Angeles Sanitation District No. 21. Although much of the physical sewage infra-
structure appears in generally good condition, there have been repeated failures of the
pump stations needed to lift flows to the regional collectors. Presently, there are no sewer
lines in place in the developed southeastern end of the 1,250-acre development known
as the Country Estates. Approximately 144 lots are utilizing on-site wastewater disposal
systems. Installation of infrastructure is needed within the Tres Hermanos Ranch as well.
Water
Water for City residents is supplied by the Walnut Valley Water District, which receives its
water supply from the Three Valleys Municipal Water District and ultimately from the
Metropolitan Water District (MWD) of Southern California. Almost all of the water supply is
purchased from MWD, which imports water from the Colorado River Aqueduct (a small
portion comes from Northern California through the State Water Project). Domestic water
supply is not expected to limit development during the planning period.
Storm Water Drainage
Flood control is provided by the County Flood Control District. Flood control facilities are
in fairly good condition. Development proposals are assessed for drainage impacts and
required facilities. With these existing facilities and review procedures in place, the City’s
flood control system is not expected to limit development during the planning period.
3. Land Costs
Land represents one of the most significant components of the cost of new housing.
Land values fluctuate with market conditions, and the recent downturn in the housing
market has affected land values negatively. Changes in land prices reflect the cyclical
nature of the residential real estate market.
A major constraint to providing affordable housing on remaining vacant hillside parcels
in Diamond Bar is the high cost of construction in hillside areas. Another cost constraint
Diamond Bar 2013-2021 Housing Element IV. Constraints
IV-18 January 2014
for construction in areas with steep topography is the low ratio of developable area to
total land area. Residential projects in hillside areas have large amounts of open space
and only about 25-30% developable land.
4. Construction Costs
Construction cost is affected by the price of materials, labor, development standards
and general market conditions. The City has no influence over materials and labor costs,
and the building codes and development standards in Diamond Bar are not substantially
different than most other cities in Los Angeles County. Construction costs for materials
and labor have increased at a slightly higher pace than the general rate of inflation
according to the Construction Industry Research Board.
5. Cost and Availability of Financing
The recent crisis in the mortgage industry that began in 2008 affected the availability and
cost of real estate loans, although the long-term effects are unpredictable. One of the
most significant changes has been a tightening of mortgage underwriting standards,
which has had greater impacts on low-income families than other segments of the
community. For those with good credit ratings, interest rates have been at historic lows,
resulting in increased affordability.
Diamond Bar is similar to most other communities with regard to private sector home
financing programs. As discussed in the previous chapter, Diamond Bar utilizes tax
exempt multi-family revenue bonds which provide a lower interest rate than is available
through conventional financing. This program helps to address funding for low-income
multi-family projects.
Under state law, it is illegal for real estate lending institutions to discriminate against entire
neighborhoods in lending practices because of the physical or economic conditions in
the area (“redlining”). In monitoring new construction sales, re-sales of existing homes,
and permits for remodeling, it would not appear that redlining is practiced in any area of
the City.
C. Fair Housing
State law also prohibits discrimination in the development process or in real property
transactions, and it is the City’s policy to uphold the law in this regard. As a participating
city in the Los Angeles County Community Development Block Grant (CDBG) program,
the City of Diamond Bar has access to services of the Long Beach Fair Housing
Foundation for fair housing outreach and education, and counseling on housing
discrimination complaints.
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V. HOUSING ACTION PLAN
Chapters II through IV of the Housing Element describe the housing needs, opportunities
and constraints in the City of Diamond Bar. The following Housing Action Plan presents
the City's eight-year Housing Plan for the 2013-2021 planning period. This Plan sets forth
Diamond Bar's goals, policies, and programs to address the identified housing needs of
the City.
A. Goals and Policies
It is the overall goal of the plan that there be adequate housing in the City, both in
quality and quantity, to provide appropriate shelter for all without discrimination.
The goals and policies of the Housing Element presented in the following section address
Diamond Bar's identified housing needs and are implemented through a series of housing
programs offered through the Community Development Department. Within this
overarching goal, the City has established goals and policies to address the
development, maintenance and improvement of the housing stock.
GOAL 1 Consistent with the Vision Statement, preserve and conserve the existing
housing stock and maintain property values and residents' quality of life.
Policy 1.1 Continue to offer home improvement and rehabilitation
assistance to low- and moderate-income households, including
seniors and the disabled.
Policy 1.2 Continue to use the Neighborhood Improvement Program to
bring substandard units into compliance with City codes and
improve overall housing conditions in Diamond Bar.
Policy 1.3 Promote increased awareness among property owners and
residents of the importance of property maintenance to long-term
housing quality.
GOAL 2 Consistent with the Vision Statement, provide opportunities for development
of suitable housing to meet the diverse needs of existing and future residents.
Policy 2.1 Provide favorable home purchasing options to low- and
moderate-income households through County and other
homebuyer assistance programs.
Policy 2.2 Continue outreach and advertising efforts to make more residents
aware of homebuyer assistance programs and to enhance
program utilization.
Policy 2.3 Maintain affordability controls on government-assisted housing
units in the City.
Policy 2.4 Facilitate the development of second units as a means to provide
affordable housing opportunities in existing neighborhoods.
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GOAL 3 Provide adequate sites through appropriate land use and zoning
designations to accommodate future housing growth.
Policy 3.1 Maintain an inventory of potential sites available for future housing
development.
Policy 3.2 Limit development of vacant Medium High Density (RMH) and
High Density (RH) designated properties to multi-family use.
Policy 3.3 Integrate multi-family residential uses within the Tres Hermanos
Specific Plan.
Policy 3.4 Coordinate with local colleges and universities in provision of
housing for faculty and staff.
GOAL 4 Mitigate potential governmental constraints which may hinder or discourage
housing development in Diamond Bar.
Policy 4.1 Continue to provide regulatory incentives and concessions to
facilitate affordable housing development in the City.
Policy 4.2 Promote the expeditious processing and approval of residential
projects that meet General Plan policies and City regulatory
requirements.
Policy 4.3 Consider granting parking exceptions, on a case by case basis,
for multi-family projects. Pursuant to the City's Affordable Housing
Incentives Ordinance, provide parking reductions for projects with
an affordable housing component.
Policy 4.4 Periodically review City regulations, ordinances, departmental
processing procedures and residential fees related to
rehabilitation and/or construction to assess their impact on
housing costs, and revise as appropriate.
GOAL 5 Consistent with the Vision Statement, encourage equal and fair housing
opportunities for all economic segments of the community.
Policy 5.1 Continue to enforce fair housing laws prohibiting arbitrary
discrimination in the building, financing, selling or renting of
housing on the basis of race, religion, family status, national origin,
physical handicap or other such circumstances.
Policy 5.2 Refer persons with fair housing complaints to the appropriate
agency for investigation and resolution.
Policy 5.3 Encourage apartment managers and owners to attend fair
housing seminars offered by the Apartment Association of Greater
Los Angeles.
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V-3 January 2014
B. Housing Programs
The goals and policies contained in the Housing Element address Diamond Bar's
identified housing needs, and are implemented through a series of housing programs
offered through Development Services Department. Housing programs define the
specific actions the City will undertake to achieve the stated goals and policies.
According to §65583 of the Government Code, a city's housing programs must address
the following five major areas:
Conserving the existing supply of affordable housing;
Assisting in the provision of housing;
Providing adequate sites to achieve a variety and diversity of housing;
Removing governmental constraints as necessary; and
Promoting equal housing opportunity
Diamond Bar's housing plan for addressing unmet needs, removing constraints, and
achieving quantitative and qualitative objectives is described in this section according
to the above five areas. The program summary (Table V-1, beginning on page V-12)
included at the end of this chapter specifies for each program eight-year objective(s),
funding source(s), and agency responsible for implementation of the program.
Conserving the Existing Supply of Affordable Housing
Conserving and improving the housing stock is an important goal for Diamond Bar.
Although the majority of the City's housing stock is in good condition, about half of the
housing stock is over 30 years old, the age when most homes begin to require major
rehabilitation improvements. By identifying older residential neighborhoods for potential
housing rehabilitation, the City has taken a proactive approach to maintaining the
quality of its current housing stock. The focus neighborhoods identified by this Plan as
evidencing physical problem conditions can be specifically targeted for City housing
improvement assistance.
1. Residential Neighborhood Improvement Program
The City implements a proactive Neighborhood Improvement Program and neighbor-
hood inspections are conducted on a regular basis throughout the entire City. The
checklist for residential violations includes inoperable vehicles, trash storage, parking on
paved areas only, structure maintenance, landscape maintenance, and fence and wall
maintenance. After the neighborhood inspection, letters are sent out to all property
owners in areas where violations have been observed. A follow-up inspection will be
conducted, at which time any noticed properties found to be in violation of the
Municipal Code are subject to a $100 citation.
When problems are observed, inspectors may refer residents to the Single Family
Rehabilitation loan program.
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Eight-year objective: Continue to implement the code enforcement program,
and direct eligible households to available rehabilitation assistance in order to
correct code violations. Provide focused code enforcement and rehabilitation
assistance for 5 to 6 households in neighborhoods evidencing concentrations of
deteriorating units.
2. Home Improvement Program
The City uses CDBG funds for minor home repair through the Home Improvement
Program, where low/moderate income householders may receive a $5,000 grant and/or
$10,000 no interest loan for home repair and rehabilitation.
Eight-year objective: Minor repair and rehabilitation for 10 units annually.
3. Single-Family Rehabilitation Program
Diamond Bar participates in the Los Angeles County Single Family Rehabilitation Program
which assists low/moderate income (up to 120% of AMI) single-family homeowners who
need property rehabilitation. The maximum loan amount is $25,000, although loan
amounts typically vary from $15,000 to $25,000. This program is promoted on the City’s
website and through personal contact with code enforcement staff. Since the program
is funded and operated by Los Angeles County, the City has no control over total
funding amounts or number of persons served.
Eight-year objective: The City will continue to advertise the County program,
which provides rehabilitation loans to qualified low- and moderate-income
homeowners, on the City’s website and through code enforcement staff.
4. Section 8 Rental Assistance Program
The Section 8 Rental Assistance Program extends rental subsidies to extremely-low- and
very-low-income households who spend more than 30% of their gross income on housing.
Rental assistance not only addresses housing affordability, but also overcrowding by
assisting families that may be "doubling up" in order to afford rent. The Los Angeles
County Housing Authority coordinates Section 8 rental assistance on behalf of the City.
Eight-year objective: Continue to direct eligible households to the County Section
8 program.
5. Preservation of Assisted Housing
Diamond Bar contains only one assisted housing project, the 149-unit Seasons
Apartments (formerly "Heritage Park") for senior citizens. This project was constructed in
1988 and was originally financed under the Los Angeles County Multi-Family Mortgage
Revenue Bond program. The project was refinanced in November 1999 under the
California Community Development Authority's Multi-Family Housing Re-funding Bond,
and was transferred to the Corporate Fund for Housing, a non-profit organization.
According to the terms of the new bond agreement, income restrictions for residents
and corresponding rent limits were set. For the duration of the bond, which expires
December 2, 2034, all units will be affordable: 30 units (20%) will be very-low-income, 82
Diamond Bar 2013-2021 Housing Element V. Housing Action Plan
V-5 January 2014
units (55%) will be low-income, and 37 units will be moderate-income (defined as 100%
AMI).
Eight-year objective: Preserve 100% of the 149 low- and moderate-income units in
the Seasons Apartments.
6. Mobile Home Park Preservation
There are two mobile home parks in Diamond Bar, both located in the western portion of
the City: Diamond Bar Estates and Walnut Creek Estates. These mobile home parks were
developed before incorporation of the City on land previously designated as Industrial
under the County's jurisdiction. The Diamond Bar General Plan Land Use Map adopted in
1995 designated both mobile home parks "residential" in order to preserve their status
and prevent future inconsistencies. This designation in the General Plan works to preserve
the parks since any proposed land use change would require an amendment to the
City's General Plan and Zoning Ordinance, as well as adherence to State mobile home
park closure requirements.
Eight-year objective: The City will continue to support preservation of its two
mobile home parks as important affordable housing resources.
Assisting in the Provision of Housing
To enable more households to attain homeownership in Diamond Bar, the City
participates in two mortgage assistance programs: the Homebuyer Assistance Program
and the Mortgage Credit Certificate (MCC). These programs are very important given
that housing prices in Diamond Bar rank among the highest in eastern Los Angeles
County and northern Orange County. The City is also supportive of the development of
senior housing to meet the needs of its growing senior population and multi-family rental
housing for lower-income households, including working families and university students.
7. First-Time Homebuyer Assistance Programs
Los Angeles County offers a first-time homebuyer assistance program and Mortgage
Credit Certificates. To be eligible, families must meet the specified income requirements
and be able to pay a 1% down payment on their home. The maximum sales price for a
home through the HOP in 2013 is $362,790. The maximum price of a home purchased in
conjunction with the Mortgage Credit Certificate program in 2013 is $673,615. The City of
Diamond Bar provides referral information to prospective buyers at the public counter
and on the City website.
Home Ownership Program (HOP)
The Los Angeles County Home Ownership Program (HOP) provides zero-interest loans
with no repayment due until the home is sold, transferred, or refinanced. Maximum loan
amount is $60,000 or 25% of the purchase price, whichever is the least. The loan is
secured by a second trust deed and a promissory note. The home must be owner -
occupied for the life of the loan.
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V-6 January 2014
Mortgage Credit Certificate (MCC)
The Mortgage Credit Certificate (MCC) program is a federal program that allows
qualified first-time homebuyers to take an annual credit against federal income taxes of
up to 15% of the annual interest paid on the applicant's mortgage. This enables
homebuyers to have more income available to qualify for a mortgage loan and make
the monthly mortgage payments. The value of the MCC must be taken into considera-
tion by the mortgage lender in underwriting the loan and may be used to adjust the
borrower's federal income tax withholding. The MCC program has covenant restrictions
to ensure the affordability of the participating homes for a period of 15 years. MCCs can
be used in conjunction with the Home Ownership Program (HOP).
Eight-year objective: The City will advertise these programs and provide
information to interested homebuyers. In addition, the City will work with realtors to
make them aware of these programs.
8. Senior and Workforce Housing Development
With a growing portion of the City's population 65 years of age and above, Diamond Bar
will experience a significant need for senior housing and services. Particularly those
seniors 75 years and older will begin to require housing with a supportive service
component. The City currently has only one senior housing facility, the Seasons
Apartments.
Occupations for which high housing costs make it difficult to live in the community where
the householder is employed include teachers, police and firefighters. Several colleges
and universities are also located within commuting distance of Diamond Bar. The City will
coordinate with these institutions to identify potential partnership opportunities for
affordable faculty/staff housing.
The City will assist in establishing a second senior facility and developing workforce
housing, including units affordable to very-low- and extremely-low-income persons as
well as units with 3-4 bedrooms suitable for large families, if feasible, in several ways. First,
the City will identify suitable sites for development in the Housing and Land Use Elements,
including zoning to encourage and facilitate low-cost housing options such as SROs.
Second, the City will offer regulatory incentives, and/or direct financial assistance
appropriate to the project. The following are among the types of incentives which may
be provided:
Contributions to off-site improvements (e.g., traffic mitigation, infrastructure
upgrades)
Flexible development standards (e.g., reduced parking, reduced open space,
modified setbacks)
Density bonuses
City support to developers in affordable housing funding applications
Reduction in development fees
Direct financial assistance
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V-7 January 2014
It must be recognized that the City’s ability to offer direct financial subsidies is limited,
particularly in light of current fiscal conditions. The City has no local source of housing
assistance funds, and its CDBG revenue is only about $300,000 per year (see Chapter III
for further discussion of the City’s financial resources). Given these financial limitations,
the City’s primary efforts to encourage and facilitate affordable housing production are
through its land use regulations and staff support to interested developers in applying for
grant funds, and cooperation with the Los Angeles County Community Development
Commission on its assistance programs.
Pursuant to the City's Affordable Housing Incentives Ordinance, the City provides
modified development standards, including parking reductions, for senior and affordable
projects. A portion of the City's CDBG funds can be used to help finance senior and
workforce housing projects. New housing developments in Diamond Bar may also be
eligible for funding sources identified in the Resources chapter of the Element. Typically,
local assistance can serve as gap financing to bridge the difference between the total
project cost and the equity investment plus debt.
Eight-year objective: The City will identify and evaluate sites suitable for new senior
and workforce housing. The City will post information on the City website during
the first year of the planning period regarding the City's interest in assisting in the
development of senior and workforce housing, provide information on available
regulatory and financial incentives, and assist developers in applying for funds.
The City will also contact local colleges and universities annually to identify
potential partnership opportunities for affordable housing. The City’s quantified
objectives for housing production during the 2013-2021 planning period are
described in Table V-2 and include 490 lower-income units and 190 moderate-
income units. Moreover, the City is actively engaged in promoting the Kmart
property as a mixed-use development opportunity in its economic development
marketing materials that are provided at International Council of Shopping
Centers (ICSC) conferences and other venues (see also the discussion of this
property in Appendix B).
Providing Adequate Housing Sites and Facilitating Infill Opportunities
to Achieve a Variety and Diversity of Housing
A major element in meeting the housing needs of all segments of the community is the
provision of adequate sites for all types, sizes and prices of housing. The City's General
Plan, Development Code and specific plans dictate where housing may be built,
thereby affecting the availability of land for residential development. Specific locations
for housing sites are depicted in the tables and maps presented in Appendix B.
9. Land Use Element and Zoning
The Land Use Element of the General Plan, as discussed in Chapter III, provides for a
variety of housing types in Diamond Bar, with densities ranging from one unit per acre to
30 dwelling units per acre, and higher densities can be achieved through the City's
density bonus provisions and through development agreements. Current zoning
designations provide adequate sites with appropriate zoning to accommodate the
Diamond Bar 2013-2021 Housing Element V. Housing Action Plan
V-8 January 2014
City’s total housing need of 1,146 units identified in the RHNA at all income levels for the
2014-2021 projection period (see discussion in Appendix B).
The City shall comply with the “no net loss” provisions of Government Code §65863
through the implementation of an ongoing project-by-project evaluation process to
ensure that adequate sites are available to accommodate the City’s RHNA share
throughout the planning period. The City shall not reduce the allowable density of any
site in its residential land inventory, nor approve a development project at a lower
density than assumed in the land inventory, unless both of the following findings are
made:
a) The reduction is consistent with the adopted General Plan, including the
Housing Element; and
b) The remaining sites identified in the Housing Element are adequate to
accommodate the City’s share of regional housing need pursuant to
Government Code §65584.
If a reduction in residential density for any parcel would result in the remaining sites in the
Housing Element land inventory not being adequate to accommodate the City’s share
of the regional housing need pursuant to §65584, the City may reduce the density on
that parcel if it identifies sufficient additional, adequate and available sites with an equal
or greater residential density so that there is no net loss of residential unit capacity.
An accurate land inventory of sites suitable for residential development shall be made
available to interested parties at the Planning Department office and on the City’s
website.
Eight-year objective: Maintain adequate sites for housing development at all
income levels in conformance with the RHNA and ensure compliance with No Net
Loss requirements.
10. Mixed Use Development
The City is supportive of mixed-use development, which could provide housing close to
transit and places of employment. The Specific Plan (SP) overlay designation can
facilitate large-scale development areas (e.g., Tres Hermanos) in which residential,
commercial, recreational, public facilities, and other land uses may be permitted , or the
redevelopment of existing underutilized properties. The City will consider potential
underutilized areas where higher-density mixed-use infill or redevelopment may be
appropriate, such as the Kmart property or the light industrial area in the northwestern
portion of the city near the Metrolink station (see also the discussion of this property in
Appendix B).
The City will encourage property owners and developers to pursue mixed-use
development where appropriate to accommodate a portion of the lower-income
housing needs during this planning period. Mixed-use can also reduce vehicle trips, make
more efficient use of land and parking areas, and facilitate energy conservation.
Eight-year objective: The City will prepare a handout and marketing materials
encouraging mixed-use development where appropriate and make it available
Diamond Bar 2013-2021 Housing Element V. Housing Action Plan
V-9 January 2014
to interested developers during the first year of the planning period. A review of
potential areas that may be appropriate for mixed-use development will be
initiated by 2015 as part of a comprehensive General Plan update.
11. Second Units
The City’s Development Code permits second units by right in the RR and RL Districts.
Second units are allowed on lots between 10,000 and 20,000 square feet in size. The
maximum size of the second unit is 600 square feet. If the lot is over 20,000 square feet,
the maximum size of the second unit is up to 1,200 square feet. A second unit may be
rented.
Eight-year objective: Second units can contribute to the provision of lower cost
rental housing, particularly for seniors. The City will continue to encourage
construction of second dwelling units pursuant to the provisions of its Second Unit
Ordinance, and will make an informational handout available for distribution at
the public counter.
12. Emergency Shelters and Transitional/Supportive Housing
Senate Bill 2 of 2007 strengthened planning requirements for emergency shelters and
transitional/supportive housing. The Development Code allows emergency shelters by-
right in the Light Industry (I) zone in compliance with SB 2 and also allows transitional and
supportive housing as a residential use subject to the same standards as other residential
uses of the same type in the same zone. The City will also continue to cooperate with the
San Gabriel Valley Council of Governments in its efforts to develop a regional strategy for
addressing homelessness.
Eight-year objective: Continue to facilitate emergency shelters and transitional/
supportive housing, and continue participating in the SGVCOG homeless study to
address homelessness.
13. Redevelopment of Underutilized Sites
Some commercial properties in Diamond Bar that were originally developed 20-30 years
ago are now “underutilized” and have the opportunity to take advantage of
contemporary land use and design through redevelopment. The City will encourage
interested owners of such properties to pursue redevelopment that includes a mixed-use
or multi-family residential component. Incentives the City may offer to encourage and
facilitate redevelopment include the following:
Contributions to off-site improvements (e.g., traffic mitigation, infrastructure
upgrades)
Flexible development standards (e.g., reduced parking, reduced open space,
modified setbacks)
Density bonuses
City support to developers in affordable housing funding applications
Reduction in development fees
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Direct financial assistance
Eight-year objective: Encourage interested property owners to pursue
redevelopment of underutilized properties through the provision of incentives and
concessions.
Removing Governmental Constraints
Under current state law, the Housing Element must address, and where legally possible,
remove governmental constraints affecting the maintenance, improvement, and
development of housing. The following programs are designed to mitigate government
constraints on residential development and facilitate the development of a variety of
housing.
14. Affordable Housing Incentives/Density Bonus
In order to specifically facilitate the development of affordable housing, the City utilizes
Affordable Housing Incentives/Density Bonus Provisions (Development Code Chapter
22.18). Incentives provided for in Chapter 22.18 apply to developments of five or more
dwelling units. If a density bonus and/or other incentives cannot be accommodated on
a parcel due to strict compliance with the provisions of the Development Code, the
Council is authorized to waive or modify the development standards as necessary to
accommodate all bonus units and other incentives to which the development is entitled.
Incentives will include a reduction in the required off-street parking pursuant to SB 1818
and allowing carports rather than garages for lower-income apartments.
Eight-year objective: The City will continue to encourage the production of
affordable housing through the use of density bonus, and provide a handout
summarizing the benefits and requirements of affordable housing incentives/
density bonus provisions. The summary handout will be prepared and distributed
to the development community. These incentives and provisions will be
particularly important to potential developers of affordable senior housing.
15. Efficient Project Processing
The City is committed to a streamlined development process, and has adopted
procedures to facilitate project processing. A prospective applicant or agent proposing
development is strongly encouraged to request a pre-application conference with the
Community Development Department before formal submittal of an application.
The purpose of this conference is to inform the applicant of City requirements as they
apply to the proposed development project, review the procedures outlined in the
Development Code, explore possible alternatives or modifications, and identify
necessary technical studies and required information relating to future entitlement
review.
Eight-year objective: The City will continue to offer streamlined development
processing, and will periodically review departmental processing procedures to
ensure efficient project processing.
Diamond Bar 2013-2021 Housing Element V. Housing Action Plan
V-11 January 2014
Promoting Equal Housing Opportunities
To adequately meet the housing needs of all segments of the community, the housing
plan must include program(s) that promote housing opportunities for all persons
regardless of race, religion, gender, family size, marital status, ancestry, national origin,
color, age, or physical disability.
16. Fair Housing Program
As a participating city in the Los Angeles County CDBG program, Diamond Bar has
access to the services of the San Gabriel Valley and Long Beach Fair Housing Foundation
for fair housing outreach and education, and counseling on housing discrimination
complaints. The City will continue to advertise the fair housing program through
placement of fair housing service brochures at the public counter, at the Senior Center,
through the City's newsletter, and on the City website. Apartment owners and managers
are among the most important groups to educate about fair housing issues, rights and
responsibilities. The Apartment Association of Greater Los Angeles conducts seminars on
state, federal and local Fair Housing laws and problems of housing. In order to bring up
these issues in the local community, the City will sponsor a seminar at which the
Apartment Association makes a presentation and initiates discussion of fair housing issues
with local apartment owners and managers.
Eight-year objective: The City will continue to promote fair housing practices,
provide educational information on fair housing to the public, and cooperate with
the Greater Los Angeles Apartment Association in providing fair housing
information to landlords and at libraries, senior centers, recreation centers, and
Social Security and employment offices. The City will continue to refer fair housing
complaints to the San Gabriel Valley and Long Beach Fair Housing Foundation,
and maintain an open dialogue with the Foundation regarding the nature of
complaints received.
17. Reasonable Accommodation for Persons with Disabilities
Senate Bill 520 of 2001 requires cities to remove constraints or make reasonable
accommodations for housing occupied by persons with disabilities. The City will continue
to implement adopted procedures for reviewing and approving requests for reasonable
housing accommodations pursuant to SB 520.
Eight-year objective: The City will continue to implement reasonable
accommodation procedures for persons with disabilities in compliance with SB
520.
Diamond Bar 2013-2021 Housing Element V. Housing Action Plan
V-12 January 2014
Table V-1
Housing Implementation Program Summary
Housing Program Program Goal
Eight-Year Objective(s)
and Time Frame
Funding
Source(s)
Responsible
Department
Conserving the Existing Supply of Affordable Housing
1. Residential
Neighborhood
Improvement
Program
Proactive program conducts
neighborhood inspections on a
regular basis throughout entire
City.
Provide citywide focused code
enforcement linked with rehabilitation
assistance. Implementation ongoing.
CDBG Community
Development Dept.
2. Home Improvement
Program
Improve neighborhoods
evidencing deferred maintenance
through property maintenance
and rehab.
Provide minor repair/rehab to 10 units
annually. Implementation ongoing.
Volunteers Community
Development Dept.
3. Single-Family
Rehabilitation
Program
Provide loans to lower-income
homeowners to help them
rehabilitate their homes.
Provide ongoing advertisement of
loans available through the County for
qualified homeowners. Implementation
ongoing.
CDBG; HOME Community
Development Dept.;
County Community
Development
Commission
4. Section 8 Rental
Assistance Program
Provide rental subsidies to very
low-income households.
Continue current levels of rental
assistance and direct eligible
households to the County program.
Implementation ongoing.
HUD Los Angeles County
Housing Authority
5. Preservation of
Assisted Housing
Preserve existing stock of
subsidized housing.
Preserve 149 low/mod units in The
Seasons Senior Apartments.
Implementation ongoing.
None required Community
Development Dept.
6. Mobile Home Park
Preservation
Support preservation of City's two
mobile home parks as affordable
housing.
Maintain residential zoning, and
enforce State closure requirements as
necessary. Implementation ongoing.
None required Community
Development Dept.
Assisting in the Provision of Housing
7. First-time
Homebuyer
Assistance Programs
Expand homeownership
opportunities for low- and
moderate-income homebuyers.
Provide 6 HOPs and 6 MCCs annually
based on availability. Implementation
ongoing.
CDBG, HOME County Community
Development
Commission
8. Senior and
Workforce Housing
Development
Provide additional senior and
affordable rental housing to
address City's growing senior
population, and housing
overpayment among renters.
Evaluate sites, contact property owners
within two years. Coordinate with local
colleges and universities.
CDBG, Tax
Credits, other
Community
Development Dept.
County Community
Development
Commission
Providing Adequate Residential Sites
9. Land Use Element
and Zoning
Provide adequate sites at varying
densities for future housing
development.
Maintain adequate sites commensurate
with the RHNA.
General Fund Community
Development Dept.
10. Mixed Use
Development
Provide expanded areas for
mixed residential development in
places close to employment.
Encourage mixed-use development in
appropriate areas to meet a portion of
the City’s lower-income housing needs.
General Fund Community
Development Dept.
11. Second Units Provide opportunities for
scattered second unit rentals
integrated in single-family
neighborhoods.
Make available an informational
handout on second units throughout
the planning period.
General Fund Community
Development Dept.
12. Emergency Shelters
and Transitional/
Supportive Housing
Continue to facilitate the provision of
emergency shelters and
transitional/supportive housing
consistent with state law.
General Fund Community
Development Dept.
13. Redevelopment of
Underutilized Sites
Encourage and facilitate
redevelopment of underutilized
Work with interested property owners
throughout the planning period in
General Fund Community
Development Dept.
Diamond Bar 2013-2021 Housing Element V. Housing Action Plan
V-13 January 2014
Housing Program Program Goal
Eight-Year Objective(s)
and Time Frame
Funding
Source(s)
Responsible
Department
properties through provision of
incentives and concessions.
support of redevelopment projects that
include a residential or mixed-use
component.
Removing Governmental Constraints
14. Affordable Housing
Incentives/ Density
Bonus
Facilitate the production of
affordable housing through
provision of regulatory and
financial assistance.
Continue to facilitate production of
affordable and senior housing through
density bonus provisions consistent
with state law.
General Fund Community
Development Dept.
15. Efficient Project
Processing
Provide efficient development
processing procedures
Continue to offer streamline
development processing, and
periodically review procedures.
Implementation ongoing.
General Fund Community
Development Dept.
Promoting Equal Housing Opportunities
16. Fair Housing
Program
Further fair housing practices in
the community.
Continue to provide educational
information on fair housing to the
public, and refer fair housing
complaints to the San Gabriel Valley
and Long Beach Fair Housing
Foundation.
General Fund,
CDBG
Community
Development Dept.;
Long Beach Fair
Housing Foundation
17. Reasonable
Accommodation for
Persons with
Disabilities
Allow modifications to land use or
building regulations as necessary
to ensure that persons with
disabilities have reasonable use
and enjoyment of their homes in
conformance with SB 520.
Continue to implement the Reasonable
Accommodation ordinance throughout
the planning period.
General Fund Community
Development Dept.
Table V-2
Quantified Objectives, 2013-2021
City of Diamond Bar
Income Category
Totals Ex. Low V. Low Low Mod Above Mod
New constructiona 154 154 182 190 466 1,146
Rehabilitation 25 25 50
Conservationb 76 82 37 195
a Quantified objective for new construction is for the period 1/1/2014 – 10/1/2021 per the RHNA
b Section 8 units + The Seasons senior apartments
Diamond Bar 2013-2021 Housing Element V. Housing Action Plan
V-14 January 2014
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Diamond Bar 2013-2021 Housing Element Appendix A – Evaluation of Prior Housing Element
A-1 January 2014
Appendix A
Evaluation of the Prior Housing Element
Section 65588(a) of the Government Code requires that jurisdictions evaluate the
effectiveness of the existing Housing Element, the appropriateness of goals, objectives
and policies, and the progress in implementing programs for the previous planning
period. This appendix summarizes the results of the City’s review of the housing goals,
policies, and programs of the previous housing element, and evaluates the degree to
which these programs have been implemented during the previous planning period,
2008 through 2013. The assessment concluded that the prior goals and policies are still
appropriate and no changes are required.
Table A-1 summarizes the programs contained in the previous Housing Element along
with the source of funding, program objectives, accomplishments, and implications for
future policies and actions.
Table A-2 summarizes new units built during the previous Housing Element period.
Table A-3 presents the City’s progress in meeting the quantified objectives from the
previous Housing Element.
Diamond Bar 2013-2021 Housing Element Appendix A – Evaluation of Prior Housing Element
A-2 January 2014
Table A-1
Housing Element Program Evaluation – 2008-2013
City of Diamond Bar
Housing Program Program Goal
Six-Year Objective(s)
and Time Frame
Funding
Source(s)
Responsible Department
or Agency Accomplishments and Future Actions
Conserving the Existing Supply of Affordable Housing
1. Residential
Neighborhood
Improvement Program
Proactive program conducts
neighborhood inspections on a
regular basis throughout entire
City.
Provide citywide focused code
enforcement linked with
rehabilitation assistance.
Implementation ongoing.
CDBG Development Services
Dept.
The City continued to operate the Code
enforcement program. This program is successful
and should be continued.
2. Home Improvement and
“Paint the Town”
Improve neighborhoods evidencing
deferred maintenance through
property maintenance and rehab.
Provide minor repair/rehab to 10
units annually. Implementation
ongoing.
Volunteers Development Services
Dept.; Homeowners
Associations
An average of about 6 homes per year have
participated in the Home Improvement Program.
The HIP should be continued at available funding
levels.
3. Single-Family
Rehabilitation Program
Provide loans to lower-income
homeowners to help them
rehabilitate their homes.
Provide ongoing advertisement of
loans available through the County
for qualified homeowners.
Implementation ongoing.
CDBG;
HOME
Development Services.
County LA Community
Development Commission
The City continued to promote this County
program. The program is successful and should
be continued.
4. Section 8 Rental
Assistance Program
Provide rental subsidies to very
low-income households.
Continue current levels of rental
assistance and direct eligible
households to the County program.
Implementation ongoing.
HUD Los Angeles County
Housing Authority
The City continued to coordinate with the County
on the Section 8 program. The program is
successful and should be continued.
5. Preservation of Assisted
Housing
Preserve existing stock of
subsidized housing.
Preserve 149 low/mod units in The
Seasons Senior Apartments.
Implementation ongoing.
None
required
Development Services
Dept.
The Seasons Senior Apartments continued its
affordability covenant throughout the planning
period. This program should be continued.
6. Mobile Home Park
Preservation
Support preservation of City's two
mobile home parks as affordable
housing.
Maintain residential zoning, and
enforce State closure requirements
as necessary. Implementation
ongoing.
None
required
Development Services
Dept.
The City continued to maintain zoning for mobile
home parks. No proposals to close the parks
were submitted. This program should be
continued.
Assisting in the Provision of Housing
7. First-time Homebuyer
Assistance Programs
Expand homeownership
opportunities for low- and
moderate-income homebuyers.
Provide 6 HOPs and 6 MCCs
annually based on availability.
Implementation ongoing.
CDBG,
HOME
Development Services
Dept. County Community
Development Commission
The City continued to provide information on this
County program. The program should be
continued.
8. Senior and Workforce
Housing Development
Provide additional senior and
affordable rental housing to
address City's growing senior
population, and housing
overpayment among renters.
Evaluate sites, contact property
owners within two years. Coordinate
with local colleges and universities.
CDBG,
Industry
Set-Aside,
Tax Credits,
other
Development Services
Dept. County Community
Development Commission
No new senior or affordable housing units were
developed during the planning period, however
additional land was rezoned for multi-family
housing (see Program 9). This program should
be continued.
Diamond Bar 2013-2021 Housing Element Appendix A – Evaluation of Prior Housing Element
A-3 January 2014
Housing Program Program Goal
Six-Year Objective(s)
and Time Frame
Funding
Source(s)
Responsible Department
or Agency Accomplishments and Future Actions
Providing Adequate Residential Sites
9. Land Use Element and
Zoning
Provide adequate sites at varying
densities for future housing
development.
Conduct an evaluation of candidate
sites for higher density development
and identify sufficient sites to
accommodate at least 466 additional
lower-income multi-family units at a
density of 30 units/acre in 2011;
create a new Very High Density land
use category and complete the
rezoning of selected sites by
December 2011. Report annually as
part of the General Plan
Implementation Report on progress
in identifying and rezoning sites.
General
Fund
Development Services
Dept.
In 2013 the City amended the General Plan to
create a new RH-30 land use district and rezoned
property to RH-30 within the Tres Hermanos area
to accommodate 490 multi-family units by-right
(Ordinance No. 07-2013). This zone change
satisfies all the requirements of Government
Code §65583.2(h) and (i). This program should
be revised to reflect prior accomplishments.
10. Mixed Use Development Provide expanded areas for mixed
residential development in places
close to employment.
Encourage mixed-use development
in appropriate areas to meet a
portion of the City’s lower-income
housing needs.
General
Fund
Development Services
Dept.
No mixed use projects were approved. This
program should be continued.
11. Second Units Provide opportunities for scattered
second unit rentals integrated in
single-family neighborhoods.
Development informational handout
on second units by 2010.
General
Fund
Development Services
Dept.
The City continued to encourage second units
throughout the planning period. This program
should be continued.
12. Emergency Shelters and
Transitional/ Supportive
Housing
Amend the Municipal Code within one
year of Housing Element adoption to
1) identify a zone where emergency
shelters may be established; and
2) provide that transitional/supportive
housing is a residential use subject
only to the same requirements as
other residential uses of the same
type in the same zone.
General
Fund
Development Services
Dept.
The City amended the Code in 2013 (Ordinance
No. 04-2013) to allow emergency shelters by-
right in the Light Industry zone, and allow
transitional and supportive housing subject to the
same regulations and procedures as apply to
other residential uses of the same type in the
same zone. This program should be revised to
reflect prior accomplishments.
13. Redevelopment of
Underutilized Sites
Encourage and facilitate
redevelopment of underutilized
properties through provision of
incentives and concessions.
Work with interested property owners
throughout the planning period in
support of redevelopment projects
that include a residential or mixed-use
component.
General
Fund
Development Services
Dept.
The City has continued to encourage the
redevelopment of underutilized sites, although
due to the economic downturn no applications
were received during the planning period. This
program should be continued.
Diamond Bar 2013-2021 Housing Element Appendix A – Evaluation of Prior Housing Element
A-4 January 2014
Housing Program Program Goal
Six-Year Objective(s)
and Time Frame
Funding
Source(s)
Responsible Department
or Agency Accomplishments and Future Actions
Removing Governmental Constraints
14. Affordable Housing
Incentives/ Density
Bonus
Facilitate the production of
affordable housing through
provision of regulatory and
financial assistance.
Consider appropriate changes to the
Development Code to address SB
1818 by 2010.
General
Fund
Development Services
Dept.
The City’s Density Bonus Ordinance was revised
in 2013 to reflect current state law (Ordinance
No. 04-2013). This program should be revised to
reflect prior accomplishments.
15. Efficient Project
Processing
Provide efficient development
processing procedures
Continue to offer streamline
development processing, and
periodically review procedures.
Implementation ongoing.
General
Fund
Development Services
Dept.
The City continued to offer efficient permit
processing. This program should be continued.
Promoting Equal Housing Opportunities
16. Fair Housing Program Further fair housing practices in
the community.
Provide educational information on
fair housing to the public, and
sponsor seminar in 2008-09. Refer
fair housing complaints to the San
Gabriel Valley Fair Housing Council,
Long Beach Fair Housing
Foundation, and Housing Rights
Center, and develop ongoing
dialogue regarding nature of
complaints received. Implementation
ongoing.
General
Fund,
CDBG
Development Services
Dept.; San Gabriel Valley
Fair Housing Council, Long
Beach Fair Housing
Foundation, Housing Rights
Center.
The City continued to promote the fair housing
program. This program should be continued.
17. Reasonable
Accommodation for
Persons with Disabilities
Establish procedures for reviewing
and approving modifications to
land use or building regulations
necessary to ensure that persons
with disabilities have reasonable
use and enjoyment of their homes
in conformance with SB 520.
Adopt a Reasonable
Accommodation ordinance in 2009.
General
Fund
Development Services
Dept.
The City amended the Municipal Code in 2010 to
include reasonable accommodation procedures.
This program should be revised to reflect prior
accomplishments.
Diamond Bar 2013-2021 Housing Element Appendix A – Evaluation of Prior Housing Element
A-5 January 2014
Table A-2
Residential Development Summary
City of Diamond Bar
2008-2013
Project/Site General Plan/Zoning Density
2006-2013
Total
Very
Low Low Mod Upper
The “Country,” a private gated community -Tracts 47850, 47851, 48487, 50314 and
51169 (Crystal Ridge, Oak Knoll, Emerald Ln, Woodbridge ct, Windmill Dr)
RR/RR Rural Residential 1du/acre 34 34
Vantage (Brookfield Homes) at Grand Ave Lavender and Vantage Dr PA-3SP/SP SP 170 170
Custom homes RL/RR Low Density Residential
(max.3du/acre) 3 3
Second units 1 1
Totals 1 207 208
Diamond Bar 2013-2021 Housing Element Appendix A – Evaluation of Prior Housing Element
A-6 January 2014
Table A-3
Progress in Achieving Quantified Objectives – 2008-2013
City of Diamond Bar
Program Category
Quantified
Objective Progress
New Construction*
Very Low (Ex. Low) 286 (143)
Low 180
Moderate 189 1
Above Moderate 443 207
Total 1,098 208
Rehabilitation
Very Low 1
Low 25 13
Moderate 25 15
Above Moderate
Total 50 29
Conservation
Very Low 76** 76
Low 82*** 82
Moderate 37*** 37
Above Moderate
Total 195 195
*Quantified objective and progress for new construction reflect units built
1998-2005, per the previous RHNA cycle
**46 Section 8 units + 30 senior apartments (The Seasons)
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-1 January 2014
Appendix B
Residential Land Inventory
The assumptions and methodology for the residential land inventory are provided below
and summarized in Table B-1.
Methodology for Income Category and Realistic Capacity of Vacant Sites
Table B-1 summarizes suitable sites for residential development. These parcels, shown on
Figure B-1, can accommodate a total of 1,291 dwelling units. Based on the default
density provisions of state law10, sites designated RH-30 that allow multi-family
development at 30 units/acre were assigned to the lower income category, while sites
allowing multi-family development at a density of 16 to 20 units per acre were assigned
to the moderate income category. Sites allowing single-family or multi-family residential
development at less than 16 units per acre were assigned to the above-moderate
income category.
Potential to Accommodate the RHNA
As noted in Chapter II, the City’s RHNA allocation for the 2014-2021 projection period is as
follows:
Lower-income units – 490 units
Moderate-income units – 190 units
Above-moderate units – 466 units
As shown in Table B-1, the capacity of vacant and underutilized sites is sufficient to
accommodate the City’s need in all income categories.
The City’s lower-income need is satisfied by the parcel in Tres Hermanos that was rezoned
during the 4th planning cycle (shown as Site A in Figure B-2). The rezoned site
encompasses approximately 30 acres of which approximately 16.5 acres is designated
for development at a density of 30 units per acre. An EIR was certified for the zone
change and development is permitted by-right.
Future Opportunity Sites for New High Density Infill Housing
In addition to the Tres Hermanos site described above, the City is exploring the potential
for multi-family and mixed-use development in two additional underutilized opportunity
areas (see Programs 8, 10 and 13 in Chapter V).
Kmart Site. This existing commercial center at the intersection of Diamond Bar
Boulevard and Golden Springs Drive is approximately 20 acres with an operating
Kmart store plus smaller shops (Figure B-3). The site has been underperforming for
several years. One of the City Council’s goals published in Diamond Bar’s Annual
Budget is to identify specific development opportunities to revitalize the Kmart
property in a way that provides the greatest net benefit to the community.
10 California Government Code §65583.2(c)(3)(B)(iv)
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-2 January 2014
The owner of the center has embarked on an effort, which has included the
acquisition of adjacent properties and negotiations to buy out Kmart’s lease, to
comprehensively redevelop the site. The center, which is adjoined by existing multi-
family residential uses, has potential for high-density or mixed-use residential
development, and the owner has expressed interest in a reuse plan with a high-
density residential component. A zone change would be required to allow high-
density residential or mixed-use development.
Northwest Light Industrial Area. This area is located in the northwestern portion of the
city, north of the SR-60 freeway, and is zoned for light industrial use (Figure B-4). Most
of the properties in this area are developed with light industrial uses such as auto
repair, home improvement sales, and light manufacturing businesses. A Metrolink
commuter rail station is located within walking distance immediately to the north in
the City of Industry. The portions of this area that are considered to have the greatest
potential for high-density residential or mixed-use redevelopment encompass
approximately 55 acres.
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-3 January 2014
Figure B-1
Residential Land Inventory
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-4 January 2014
Table B-1
Residential Land Inventory
City of Diamond Bar
Site (Address/APN)
Acreage Constraints
Realistic
Density
Potential Units by Income
Category
Total General Plan Zoning Lower Mod Upper
Projects Approved/Not Built
Dairy drive thru 23671 Golden Springs High Density Res RH-PD 0.62 20 du/ac 9 9
Custom homes Various lots in Country Rural Residential RR 1 du/ac 18 18
Custom homes Various lots in Country Rural Residential RR 1 du/ac 6 6
Custom homes Various lots in Country Low Density Res RR 3 du/ac 2 2
South Pointe West End of Larkstone Specific Plan SP 34.52 3 du/ac 99 99
Yeh & Millennium End of Alamo Heights Rural Residential RR 87.5 1 du/ac 53 53
Singh-Jewel Ridge End of Crooked Creek Low Density Res RL-PD 12.9 3 du/ac 16 16
Willow Heights
(Site D)
8714-002-901 8714-002-
900 8714-015-902 8714-
002-903 8714-015-001
Specific Plan SP 30 6.7 du/ac 182 182
Subtotal 0 9 376 385
Vacant Sites
Tres Hermanos Site A 8701-022-273 (30-acre
portion)
High Density
Residential-30
High Density
Residential-30
30 20-30 490 490
North End of DB 8706-008-013 and Caltrans
Path
Medium Density
Residential
Commercial Planned
Dev
approx. 1.4 12 du/ac 16 16
Summitridge 8701-013-902 Low Density Res. RPD- 20,000-2U 1.25 3 du/ac 3 3
End of Fern Hollow 8293-001-022 Rural Residential RR & RL 21.42 Hillside topography 1 du/ac 21 21
The Country at
Shadow Canyon
Various vacant lots for
custom homes
Rural Residential RR 1 du/ac 50 50
1850 S. Diamond Bar
Blvd.
8713-007-003 Medium Density
Residential
RMH & RR 13 Existing storm drain
easement
20 du/ac 260 260
2335 S. Diamond Bar
Blvd.
8292-009-004 Medium High
Density Residential
RM 1.5 16 du/ac 21 21
Subtotal 490 297 74 371
Underutilized Sites
1101 Diamond Bar
Blvd. (LDS Church)
8717-031-006 High Density
Residential
RM Approx. 4.5
acres
Approx. 2 acres developed
with church (2 acres vacant)
20 du/ac 40 40
Second Units 5 5
Subtotal 45 45
Totals 490 351 450 1,291
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-5 January 2014
Figure B-2
Tres Hermanos Site
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-6 January 2014
Figure B-3
Kmart Site
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-7 January 2014
Figure B-4
Northwest Light Industrial Area
Diamond Bar 2013-2021 Housing Element Appendix B – Residential Land Inventory
B-8 January 2014
This page intentionally left blank.
Diamond Bar 2013-2021 Housing Element Appendix C – Public Participation Summary
C-1 January 2014
Appendix C
Public Participation Summary
This summary of Housing Element public-participation efforts describes opportunities for public
involvement along with an explanation of how public comments were incorporated into the
Housing Element. In addition, prior to the adoption hearings all interested parties were given the
opportunity to review the recommended revisions.
Public participation is an important component of the planning process, and this update to the
Housing Element has provided residents and other interested parties numerous opportunities for
review and comment. Public notices of all Housing Element meetings and public hearings were
published in the local newspaper in advance of each meeting, as well as posting the notices
on the City’s website. The draft Housing Element was made available for review at City Hall,
posted on the City’s website, as well as at the Public Library. The document was also made
available to housing advocates and non-profit organizations representing the interests of lower -
income persons and special needs groups.
After receiving comments on the draft Housing Element from the State Housing and Community
Development Department, a proposed final Housing Element was prepared and made
available for public review prior to adoption by the City Council.
The following is a list of opportunities for public involvement in the preparation of this Housing
Element update.
Public Workshop November 7, 2013
Planning Commission hearing November 26, 2013
City Council adoption hearing January 21, 2014
A list of interested parties that were notified of meetings is provided in Table C-1 and a summary
of comments is provided in Table C-2.
Diamond Bar 2013-2021 Housing Element Appendix C – Public Participation Summary
C-2 January 2014
Table C-1
Public Notice List
Southern California Association of Non
Profit Housing
501 Shatto Place, Suite 403
Los Angeles, CA 90020
National Community Renaissance
Attn: John Seymour
4322 Piedmont Drive
San Diego, CA 92107
LINC Housing Corporation
110 Pine Ave., Suite 500
Long Beach, CA 90802
C & C Development
Attn: Barry Cottle
14211 Yorba Street, Suite 200
Tustin, CA 92870
City Ventures
Attn: Bill McReynolds
2850 Red Hill Avenue, Suite 200
Santa Ana, CA 92705
Jamboree Housing Corp.
Laura Archuleta
17701 Cowan Avenue, Suite 200
Irvine, CA 92614
The Related Companies of California
Frank Cardone
18201 Von Karman Ave Ste 900
Irvine, CA 92612
Abode Communities
701 East 3rd Street, Suite 400
Los Angeles, California 90013
Meta Housing
1640 S Sepulveda Blvd.
Los Angeles, CA 90025
SOCAL Housing Development Corp
9065 Haven Ave
Rancho Cucamonga, CA 91730
Mercy Housing
1500 South Grand Ave., Suite 100
Los Angeles, California 90015
City of Walnut
Community Development Director
21201 La Puente Road
Walnut, CA 91789
City of Chino Hills
Joann Lombardo
Community Development Director
14000 City Center Drive
Chino Hills, CA 91709
City of Yorba Linda
Attn: Steve Harris
Community Development Director
4845 Casa Loma Avenue
Yorba Linda, CA 92885
City of Pomona
Community Development Director
505 South Garey Avenue
Pomona, California 91766
City of Brea
Attn: Eric Nicoll
Community Development Director
1 Civic Center Circle
Brea, CA 92821
Diamond Bar 2013-2021 Housing Element Appendix C – Public Participation Summary
C-3 January 2014
Table C-2
Summary of Public Comments and Responses
Comment Response
How did SCAG determine the City’s RHNA allocation? The RHNA allocations are based on the regional growth
forecast and each city’s income distribution. The RHNA
methodology adjusts income distributions to avoid
overconcentration of lower-income households.
Could Diamond Bar’s RHNA allocation be higher in the next
Housing Element cycle?
The RHNA process for the 6th Housing Element cycle (2021-
2029) will likely begin in 2017-2018 with an update to the
regional growth forecast. It would be speculative to try and
assess Diamond Bar’s expected RHNA at that time.
Is the Tres Hermanos property in the City or the Sphere of
Influence?
The Tres Hermanos property is divided between the City of
Diamond Bar and the City of Chino Hills
What is a “non-family household”? The Census definition for “family” is 2 or more persons living
together who are related. A “non-family household” refers to
either one person living alone or a group of unrelated persons
living together.
The City should consider initiating a comprehensive General
Plan update.
A General Plan update will be proposed to the City Council for
consideration.
Other sites besides Tres Hermanos should be considered for
affordable housing.
If the City Council initiates a General Plan update, one of the
key issues would be identifying additional sites for high-density
residential or mixed-use development.
A density of 30 units/acre is not compatible with the rural
atmosphere of the Tres Hermanos area.
As required by state law, a portion of the Tres Hermanos
property was rezoned in the previous planning cycle to
accommodate the City’s assigned share of the region’s low-
income housing need.
What would be the penalty for delaying adoption of the Housing
Element?
Cities that do not adopt the 5th cycle Housing Element by
February 12, 2014 are required to prepare future Housing
Element updates on a 4-year schedule rather than the standard
8 years.
Diamond Bar 2013-2021 Housing Element Appendix C – Public Participation Summary
C-4 January 2014
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Diamond Bar 2013-2021 Housing Element Appendix D – City Council Resolution No. 2014-04
D-1 January 2014
Appendix C
Diamond Bar 2013-2021 Housing Element Appendix D – City Council Resolution No. 2014-04
D-2 January 2014
Diamond Bar 2013-2021 Housing Element Appendix D – City Council Resolution No. 2014-04
D-3 January 2014
III. RESOURCE
MANAGEMENT
ELEMENT
Diamond Bar General Plan Resource Management Element
July 25, 1995 i
RESOURCE MANAGEMENT ELEMENT
TABLE OF CONTENTS
A. INTRODUCTION.........................................................................................................III-1
B. EXISTING CONDITIONS............................................................................................III-2
C. RESOURCE MANAGEMENT ISSUES ......................................................................III-8
D. GOALS, OBJECTIVES, AND IMPLEMENTATION STRATEGIES........................III-9
LIST OF TABLES
TABLE PAGE
III-1 Local Recreational Facilities..........................................................................................III-3
Diamond Bar General Plan Resource Management Element
July 25, 1995 ii
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Diamond Bar General Plan Resource Management Element
July 25, 1995 III-1
III. RESOURCE MANAGEMENT ELEMENT
A. INTRODUCTION
Open Space Elements and Conservation Elements were first required to be a part of city and county
General Plans in 1970. Within Diamond Bar, many issues dealing with conservation also overlap issues
related to open space, such as “open space for the preservation of natural resources” and “open space for
the managed production of resources” (State of California General Plan Guidelines). As a result of this
overlap and interdependency, these two General Plan requirements have been combined into a Resource
Management Element, which is permitted under State law.
Diamond Bar recognizes its role as a responsible steward of all lands within its jurisdiction. The
Resource Management Element deals with open-space land issues, defined by Section 65560(b) of the
Government Code as “any parcel or area of land or water which is essentially unimproved and devoted to
open space use…”. Open space uses encompass four, principal categories: Natural resources; managed
production of resources; outdoor recreation; and public health and safety. The first part of this Element
addresses open space and visual resources, biological resources, and parks and recreation.
The Resource Management Element also establishes strategies for effectively managing local natural
resources to prevent waste, destruction, or neglect. This portion of the General Plan is concerned with the
conservation, development, and utilization of natural resources such as water (including reclaimed water),
energy, and the disposal and reuse of solid wastes. As recommended in state law, agriculture and mineral
resources are two other natural resources that are analyzed.
It is the intent of the Resource Management Element to:
• Create and retain an open space system which will conserve natural resources, preserve
scenic beauty, promote a healthy community atmosphere, provide open space for outdoor
recreation, and protect the public safety.
• Identify limits on the natural resources needed to support urban and rural development
within the City and its Sphere of Influence, and ensure that those resources are used
wisely and not abused.
• Provide a park, recreation and open space system which enhances the livability of urban
and suburban areas by providing parks for residential neighborhoods; preserving
significant natural, scenic, and other open space resources; and meeting the open space
and recreational needs of Diamond Bar residents.
The Resource Management Element is closely related to the Land Use Element since areas designated for
open space must be consistent with designations on the Land Use map. Areas designated as open space
for public health and safety reasons in the Resource Management Element are similarly addressed in the
Public Health and Safety Element.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-2
B. EXISTING CONDITIONS
1. Open Space and Visual Resources
Diamond Bar is well known as a hillside residential community with outstanding views of natural slopes
and ridgelines. There are a number of undeveloped areas in the City that constitute potential open space
resources. The portion of Tonner Canyon that is within the City's Sphere of Influence offers tremendous
open space opportunities and visual resources.
The natural slopes and ridges have provided a distinctive visual identify to the community’s natural and
developed areas.
2. Biological Resources
While Diamond Bar still contains several areas that support native plants and animals, these resources
have undergone considerable transition over the years. The native flora and fauna which once inhabited
the City have been largely eliminated in developed areas. Historical agricultural and recent urban
development have removed large areas of natural vegetative cover. Animals that once inhabited the
valley floor have largely been forced into nearly undisturbed areas to the southwest, south, southeast, and
east of the City limits.
The City’s Sphere of Influence encompasses the middle, 3,600 acres of Tonner Canyon, a portion of
which considered a “Significant Ecological Area” (SEA) by Los Angeles County due to its wealth of
biological resources. This portion of the canyon contains extensive stands of riparian, oak, and walnut
woodland plants, which are considered sensitive and important native plant habitats by the California
Department of Fish and Game. Tonner Canyon supports a diverse population of native animals, including
the California ground squirrel, cottontail rabbit, coyote, and deer. The canyon habitat may also support
other animals such as the endangered Stephen's kangaroo rat, several, species of mice, and possibly the
California gnatcatcher. Numerous birds also utilize this area, including several species of hawks and owls,
which are all protected under California Fish and Game laws. A sensitive species of pond turtle was also
observed in the upper portion of the canyon, although it was just outside the City limits and Sphere of
Influence.
3. Parks and Recreation
There are several existing park and recreation facilities within the City's boundaries that provide active
and passive recreational opportunities to City residents. The City has seven developed parks ranging in
size from 2 acres to 26 acres. The City also has two undeveloped parks and one joint park facility with
Walnut Valley Unified School District. Small athletic fields and playgrounds exist at the eight elementary
and two intermediate schools in the City. More extensive fields and a gymnasium exist at Diamond Bar
High School. These facilities are made available on a limited basis for use by City recreational programs
and by local athletic organizations through short term agreements with the Walnut Valley Unified School
District and the Pomona Unified School District. There are also several quasi-public and private
recreational facilities, including the Diamond Bar golf course, “The Country Estates” park, YMCA and
Little League fields on Sunset Crossing Road. Table III-1 describes local recreational facilities.
The State and National recreation agencies recommend a minimum of 2 acres of developed active public
parkland and 0.5 acres of undeveloped or passive parklands per 1,000 residents. The City ratio of 1.0
Diamond Bar General Plan Resource Management Element July 25, 1995 III-3 Table III-1 Local Recreational Facilities
Diamond Bar General Plan Resource Management Element July 25, 1995 III-4 Table III-1 Local Recreational Facilities (Continued)
Diamond Bar General Plan Resource Management Element July 25, 1995 III-5 Table III-1 Local Recreational Facilities (Continued)
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-6
acres of developed public parkland per 1,000 residents1 is under the State and National recreation
agencies recommendation, which will need to be addressed. The City will need to provide adequate park
acreage and recreation facilities to serve the need of present and future residents.
Currently, within the City there is a total of 478.3 acres of recreational facilities, including 45.4 acres of
developed parkland and 97 acres of undeveloped parkland for a total of 142.4 acres of City owned park
land. Within the City there are quasi-public parkland and/or facilities that may require user fees; these
include the Diamond Bar Golf Course, YMCA and Little League fields.
There is also a private parkland and facility which consists of “The Country Estates” park. Only residents
of “The Country Estates” can use the park which consists of 16.4 developed acres and 133.5 undeveloped
acres.
The City is located within an hour of several regional recreation and national forest areas such as the
Chino trills State Park, as well as San Gabriel and San Bernardino National Forests to the north and
northeast, which include the summer and winter resort areas of Big Bear Lake and Lake Arrowhead. The
forests provide outdoor activities as diverse as swimming, boating, hiking, camping, downhill skiing, and
cross country skiing. There are also county recreation facilities available at Schabarum Regional Park to
the west and Bonelli Regional Park to the north (which contains Puddingstone Lake).
Within the City, the 57 Freeway is designated as a proposed State Scenic Highway. It extends from the
southwest to the northeast City limits, and includes views of trees, rolling hills, grazing cattle, and snow-
capped mountains.
4. Water Resources
One of the fundamental long-term constraints for both urban and rural development is the availability and
quality of water. As throughout Southern California, water availability has become, and will remain, a
major resource constraint facing Diamond Bar. The strategies for this section focus on the actions which
must be taken to ensure the continuing supply of water needed to support Diamond Bar's future. A
complete discussion of water resources is in the Master Environmental Assessment.
Water is provided to the area by the Three Valleys Municipal Water District but locally distributed
through the Walnut Valley, Municipal Water District. Ultimately, almost all local water districts receive
most of their imported water (other than groundwater) from the Metropolitan Water District (MWD). As a
result of the recent six-year Statewide drought, the MWD has restricted local water supplies by 25 percent
through the imposition of surcharges on water that was supplied in excess of these levels. A complete
discussion of peak demand water supply requirements is in the Master Environmental Assessment. A
Master Plan of Water is being prepared by the Walnut Valley Water Municipal District which estimates a
buildout population for Diamond Bar of approximately 75,000 residents, which is higher than the
estimated buildout of the City. The degree to which the modest amount of growth projected by the
General Plan can be accommodated by the local water districts will depend on the regional availability of
water.
1 Only developed public parks are included in this figure. The 1.0 aches per 1,000 population ratio does
not include privately owned recreation facilities or the Diamond Bar Golf Course, and thus includes only the 45.4
acres of publicly owned parks.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-7
5. Energy Resources
The availability of energy resources is a growing societal concern. Urban and suburban land uses within
the City all rely on the availability of a continuing supply of affordable energy resources. However, recent
experience has been that unless society's awareness of the critical nature of energy availability is
increased, significant dislocations in the economy and local quality of life can result. Energy conservation
is not only necessary to the continued functioning of modern society, but provides immediate benefits to
individuals and businesses in utility bill savings and improved air quality. The strategies provided in this
section propose energy efficient building and land use practices. Many other actions needed to conserve
energy require cooperation with Federal and State agencies, as well as with public utilities, which have
indicated their interest in promoting energy conservation.
6. Solid Waste
Landfill disposal of solid wastes and the conservation of recyclable materials have become important
public concerns by reason of the diminishing capacity of landfill space and growing environmental
problems facing our State. For this reason, the State Legislature passed the California Integrated Waste
Management Act of 1989 (AB939). The Act, also known as Public Resources Code Section 41000
et. seq., requires each city to prepare, adopt, and implement a Source Reduction and Recycling Element
(SRRE) which identifies how that jurisdiction will divert, through a combination of source reduction,
recycling, and composting programs, 25 percent of solid wastes from landfill disposal by 1995, and 50
percent or the maximum amount feasible by the year 2000.
Since the improper disposal of hazardous wastes poses a more serious risk to the public's health and
threatens the environment in which we live, the Legislature passed AB 2707 (Public Resource Code
Section 47500 et. seq.) which requires each city to prepare a Household Hazardous Waste Element
(HHWE). The HHWE describes how the City will dispose of hazardous substances like household
cleaners, paints, pesticides, and motor oil.
7. Agriculture
The City of Diamond Bar presently has no important agricultural farmlands according to the California
Department of Conservation, Division of Land Resources Protection, and the Soil Conservation Service
of the U.S. Department of Agriculture. These agencies classify important farmland into six categories
according to soil type: Prime; potential prime; statewide important; locally important; and unique
farmlands. While none of these classifications have been applied to soils in Diamond Bar, the area did at
one time support extensive walnut groves and cattle ranches.
Over the last 30 years, the farm and ranchlands that once typified Diamond Bar have been converted to
urban and suburban uses. Prior to 1900, the production of walnuts and cattle grazing were the primary
agricultural activities within the City. Today, only scattered grazing remains, primarily on the Tres
Hermanos property in the northeastern corner of the City. This area contains the “headwaters” of Tonner
Canyon, and the upper portions of this canyon, just south of Tres Hermanos and west of Diamond Bar,
are also grazed periodically. The middle portion of Tonner Canyon, within the City's Sphere of Influence,
supports oil production, as well as the Firestone Boy Scout Reservation, and is not grazed on a regular
basis.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-8
8. Mineral Resources
The City of Diamond Bar does not contain any identified (significant) mineral resources. The State of
California has established four categories of Mineral Resource Zones (MRZs). Most of Diamond Bar is
considered in MRZ-1, which identifies areas where adequate information, indicates no significant
aggregate deposits are present. However, a particular bedrock formation (Puente) underlies scattered
portions of the City. This formation is classified as MRZ-3, which identifies, areas that may contain
aggregate mineral deposits but whose significance cannot be evaluated from available data. Based on
available data, development in Diamond Bar will have to import substantial quantities of aggregate
materials anyway, since none of the surrounding areas contain extensive deposits.
C. RESOURCE MANAGEMENT ISSUES
1. Open Space and Visual Resources
There are several major vacant side or open space areas remaining in the City, which are under various
pressures to develop. The City needs to determine which areas will be preserved and what means to use to
best assure their protection. Portions of these areas should be preserved for parks.
ISSUE ANALYSIS: There is a need to preserve open space within the City and the Sphere of
Influence and to utilize portions of these preserved open spaces for parks
and recreational uses, where feasible and safe.
2. Biological Resources
The City and its Sphere of Influence contain several areas with significant biological resources. These
areas should be considered for preservation in conjunction with important open space and visual resource
areas. This includes wildlife corridors to prevent isolation, loss of diversity biological “islands” if they are
cut off from larger and more diverse areas, and to maintain a sustainable quality (food, water, shelter,
nesting) habitat.
ISSUE ANALYSIS: There is a need to protect areas with important biological resources,
both within the City and the Sphere of Influence.
3. Parks and Recreation
The City has a variety of recreational facilities presently available for local residents. While there are
numerous facilities in the area, some local parks are small or isolated. There are few additional parks
planned for the future. As the City grows, there will be additional demands placed on existing facilities.
ISSUE ANALYSIS: There is a need to plan for additional parks and recreational facilities to
serve the growing needs of local residents through full utilization of
existing facilities within City boundaries and within the surrounding
area, additional recreation parklands are necessary to meet the
community needs.
Water is a scarce and expensive natural resource. The City already makes use of reclaimed water, and this
source will be depended on more in the future to “free up” potable water for additional domestic use. The
level of additional population growth in the City will be modest, but water may continue to be a limiting
factor in long-range planning.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-9
ISSUE ANALYSIS: The City must work with local water purveyors and landowners to
establish high water quality standards, to encourage water
conservation, preservation of natural springs, increase the use of
reclaimed water and develop additional water resources.
5. Energy
While water is the current resource shortage, there have also been short-term energy (fossil fuel)
shortages. In times of increasing population, consumption, and environmental awareness; the efficient use
of energy will continue to be an important aspect of responsible community life. There are many
educational, governmental, and private institutions nearby that are on the cutting edge of energy
technology. The City should avail itself of environmentally safe methods of resource conservation and
encourage testing of new technologies.
ISSUE ANALYSIS: The City should encourage energy conservation and innovation in
energy systems.
6. Solid waste
While the disposal of solid waste is a significant problem, recent legislation has several immediate and
specific implications for Diamond Bar. Cities are now required to reduce their production of solid waste
and implement recycling programs, as well as arrange for the disposal of hazardous household materials.
ISSUE ANALYSIS: The City should outline an integrated waste management strategy and
identify programs that will assist the City in minimizing the
environmental impacts of landfill disposal of solid wastes as mandated
by State law.
7. Agriculture
Although Diamond Bar began as an agricultural community, it has become a residential suburban
community. Cattle grazing is the only agricultural activity that remains as a reminder of this heritage and
should be left as such.
ISSUE ANALYSIS: The City needs to develop a policy dealing with the preservation of
agricultural land to the greatest extent possible.
8. Mineral Resources
There are no significant, concentrated mineral resources in Diamond Bar, with the possible exceptions of
oil and hydrocarbons
ISSUE ANALYSIS: There is no identified issue at this time.
D. GOALS, OBJECTIVES, AND IMPLEMENTATION STRATEGIES
“IT IS THE OVERALL GOAL OF THE RESOURCE MANAGEMENT ELEMENT TO PROVIDE
AND MAINTAIN ADEQUATE OPEN SPACES IN THE CITY TO SERVE THE DIVERSE
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-10
RECREATIONAL NEEDS OF ITS RESIDENTS, WHILE FOSTERING THE WISE USE OF
LIMITED NATURAL RESOURCES. “
GOAL 1 “Consistent with the Vision Statement, create and maintain an open space system
which will preserve scenic beauty, protect important biological resources, provide
open space for outdoor recreation and the enjoyment of nature, conserve natural
resources, and protect public health and safety.”
Objective 1.1 Preserve significant visual features which are within, or are visible from the City of
Diamond Bar, with an emphasis on the preservation of remaining natural hillside areas.
Strategies: 1.1.1 Develop regulations for the protection of ridgelines, slope areas, canyons, and
hilltops. Require contour or landform grading, clustering of development, or
other means to minimize visual and environmental impacts to ridgelines or
prominent slopes.
1.1.2 Require that all excess excavated and waste materials be properly removed and
disposed of, or otherwise placed so as to- become an integral part of the site
development.
1.1.3 Require that dwelling units and structures within hillside areas be sited in such a
manner as to utilize ridgelines and landscape plant materials as a backdrop for
the structures and the structures, themselves to provide maximum concealment of
cut slopes.
1.1.4 Preserve to the maximum extent feasible existing vegetation within undeveloped
hillside areas.
1.1.5 When deemed necessary by the City, require that significant vegetation be
preserved or transplanted as determined by a qualified biota report approved by
the City.
1.1.6 Pursue the preservation of areas within Diamond Bar and its Sphere of Influence,
of outstanding scenic, historic, and cultural value.
1.1.7 To the greatest extent possible, require that dwelling units, structures and
landscaping be sited in a manner which:
• Protects views for existing development,
• Retains opportunities for views from dwellings,
• Preserves or enhances vistas, particularly those seen from public places,
• Preserves mature trees, natural hydrology, native plant materials, and
areas of visual interest, and
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-11
• Permits removal of vegetation as part of a City or Fire District approved
fuel modification program.
1.1.8 Utilize grading permit procedures to ensure that site designs for development
proposals for hillside areas conform to the natural terrain, and consider the visual
aspects.
1.1.9 Work with the appropriate jurisdictions to protect remaining prominent ridges,
slopes, and hilltops in and adjacent to the City and its Sphere of Influence, such
as SEA 15, Tonner Canyon, the hills in the City of Industry, west of the 57
Freeway at Grand Avenue, the hills within the County of Los Angeles (Rowland
Heights), west of the 57 Freeway, south of Brea Canyon Cutoff Road along
Crestline Drive and above the Diamond Canyon area, the portion of Tonner
Canyon within the Chino Hills Specific Plan, and the portion of Tonner Canyon
within the City of Brea (Orange County).
1.1.10 Enact provisions and techniques that enhance groundwater recharge and local
water recovery.
1.1.11 Prepare a tree preservation ordinance that requires preservation of native trees,
such as the oak and walnut. In addition, the ordinance should emphasize retention
of mature sycamore, pepper, arroyo willow and significant trees of cultural or
historical value. The ordinance should provide a replacement and relocation
mechanism for trees when their removal is necessary.
1.1.12 New development should include the preservation of significant trees of cultural
or historical value.
1.1.13 Develop a plan to provide a mechanism for, and to pursue the preservation of
designated open space.
Objective 1.2 Maintain, protect, and preserve biologically significant areas, including SEA 15, riparian
areas, oak and walnut woodlands, and other areas of natural significance, providing only
such recreational and cultural opportunities as can be developed in a manner sensitive to
the environment.
Strategies: 1.2.1 Recognizing the significance of SEA 15 ecological resources, support further
definition of the extent and intensity of such resources to provide needed
additional information for the purpose and intent of preservation of this area.
1.2.2 Ensure that all development, including roads, proposed adjacent to riparian and
other biologically sensitive habitats avoid significant impacts to such areas.
Require that new development proposed in such locations be designed to:
• Minimize or eliminate impacts on environmentally sensitive areas,
• Protect the visual seclusion of forage areas from road intrusion by
providing vegetative buffering,
• Provide wildlife movement linkages to water, food, shelter and nesting,
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-12
• Provide vegetation that can be used by wildlife for cover along roadsides,
• Avoid intrusion of night lighting into identified areas through properly
designed lighting systems,
• Allow wildlife and migration access by use of tunnels or other practical
means,
• Replace fresh drinking water for wildlife when natural water areas are
removed or blocked, and
• To the greatest extent possible, prevent street water runoff from flowing
into natural or blueline streams.
1.2.3 In conjunction with local schools, environmental groups and volunteers, the
City may participate in environmental education programs.
1.2.4 Take an active role in pursuing the preservation of environmentally sensitive
canyon areas in their natural state.
1.2.5 To the greatest extent possible, provide for preservation of flora and fauna.
Objective 1.3 Maintain a system of recreation facilities and open space preservation which meet the
active and passive recreational needs of Diamond Bar residents of all ages.
Strategies: 1.3.1 As quickly as possible, complete a Recreational Needs Analysis to determine the
present and future recreation and park needs and update this analysis at intervals
of not more than 5 years.
1.3.2 As quickly as possible, complete and adopt a comprehensive Master Plan of
Parks which analyzes present and future recreation, park and open space
preservation needs.
1.3.3 Through the Master Plan of Parks, strive to provide neighborhood and
community park facilities, such that a rate of 5.0 acres per 1000 residents is
ultimately achieved.
1.3.4 Maintain an inventory of open lands which were set aside for open space uses
as part of previous development approvals through the County, and require
verification as to the existence of any potential open space restrictions
previously approved on the subject property, prior to accepting development
proposals.
1.3.5 Recreational Open Space shall be preserved as recreational open space unless
and until said recreational open spaces are replaced with equivalent open space
properties and facilities.
1.3.6 Pursue the development of a system of greenbelts within the community.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-13
1.3.7 Develop recreation facilities, emphasizing active and passive recreation areas.
The development of a community center, the acquisition of traditional
neighborhood parkland including community athletic fields should be pursued.
• Improve and enhance existing recreation areas,
• Pursue joint public/private development of recreation facilities,
• Develop and maintain a comprehensive inventory of recreation facilities
and update the facilities to ensure that the City's needs are being met,
• Actively pursue land acquisition for parks,
• Pursue acquisition of various hillside areas for natural parks,
• Initiate a program of identifying environmentally significant areas in the
City and the Sphere of Influence, and analyze the possibility of
protecting any unique or significant environmental features of such areas,
• Pursue protection of environmentally significant areas, and
• Pursue development of an integrated trails system within the community,
1.3.8 Work with property owners and neighboring jurisdictions to plan and locate an
untreated potable water reservoir in the upper Tonner Canyon/Tres Hermanos
Ranch area. Planning should encourage and emphasize recreational uses and
facilities that could be developed on lands surrounding the reservoir.
GOAL 2 “Consistent with the Vision Statement, identify limits on the resources needed to
support existing and future uses within the City of Diamond Bar and its Sphere of
Influence, and ensure that resources are used wisely.”
Objective. 2.1 Minimize the consumption of water through a combination of water conservation and
use of reclaimed water.
Strategies: 2.1.1 Coordinate with the local water agencies to encourage and expand the use of
reclaimed water, stored rainwater, or household gray water for irrigation.
(a) In cooperation with adjacent communities and area water purveyors,
encourage the use of reclaimed water; consider construction of dual
water systems, where feasible, for development.
(b) Work with the local water agencies and schools to promote public
education regarding conservation and advantages for reuse of water.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-14
(c) Where feasible, direct storm waters collected in streets and drainage
systems to settling basins or small lakes within parks or open space
areas, as long as it benefits and does not adversely disrupt local plants or
wildlife.
2.1.2 Prepare ordinances that allow for the implementation of feasible water
conservation technologies into new developments such as, but not limited to,
self-closing valves, installation of hot water lines, or other technology.
2.1.3 Consistent with State law, encourage the use of primarily drought-tolerant
plants, efficient design in landscape application, and the use of reclaimed water
systems.
(a) As part of the City development review of landscaping plans,
discourage installation of large areas of lawn or turf, or limit
installations to areas that require the use of grass, where feasible.
(b) Where domestic water supplies are used in the irrigation of turf areas,
encourage the use of drought tolerant vegetation.
(c) To the extent possible, encourage the preservation of existing native
trees and shrubs, as established plants are often adapted to low water
consumption.
(d) Require residential builders to provide information to prospective
buyers of new homes within the City of Diamond Bar regarding
drought-tolerant planting concepts.
(e) Require non-residential builders to provide information to prospective
buyers or tenants within the City of Diamond Bar regarding drought-
tolerant planting concepts.
(f) Where possible, require, the extensive use of mulch in landscape areas
to improve the water-holding capacity of the soil by reducing
evaporation and soil compaction.
2.1.4 Require irrigation efficiency within the City. Encourage and upgrade irrigation
systems to the most efficient system available.
2.1.5 Establish the City as a leader in the implementation of water conservation
measures through expeditious implementation of the measures outlined above.
Objective 2.2 Encourage efficient use of energy by minimizing the consumption of energy resources to
the minimal amount needed to support existing and planned land uses, through a
combination of efficient land use patterns and passive and active energy conservation
systems.
Strategies: 2.2.1 As a general principle, replace total dependence on nonrenewable, imported
energy resources with a greater reliance on locally available renewable resources
to a degree which is feasible and in accord with current technology.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-15
2.2.2 In conjunction with review of development applications, encourage the
incorporation of the following:
• Provide for clusters of buildings with protected indoor or plaza/open
areas within multiple family residential, commercial, and office project
to promote protection from the wind and sun
• Orient the maximum amount of glass possible toward the south, the side
with the greatest amount of solar collection (heat gain potential), in
combination with other measures for shading to mitigate against summer
heat
• Use appropriate building shapes and locations in order to promote
maximum feasible solar access of individual units
• Design individual buildings to maximize natural internal lighting through
interior court wells interior court areas, skylights, clerestory windows,
and energy efficient building shapes.
• Use canopies and overhangs to provide shade to windows during summer
months, while allowing for reflection of direct sunlight through the
windows during winter months (care should be taken to assure that
overhangs and canopies do not prevent sufficient light for daytime
purposes).
• Incorporate the use of drought tolerant deciduous trees in landscaping
plans, especially near buildings and around expanses of paved areas
• Incorporate drought tolerant deciduous vines, trellises, and canopies to
shade south and westward facing walls, to cool them in summer months
• Locate trees and hedges planted close to buildings so as to channel
beneficial cooling breezes through openings
2.2.3 Where possible, minimize reflective surfaces (i.e. parking lots) on the north and
east side of buildings; alternatively, where parking areas must be located to the
south or west of buildings, provide additional landscaping to reduce heat gain.
2.2.4 Investigate the feasibility of adopting an Energy Ordinance that will incorporate
retrofit provisions for the installation of energy conservation measures on
existing structures, solar pool and hot tub provisions that will discourage natural
gas-heaters as the primary energy source.
2.2.5 Implement, through the subdivision ordinance or through other appropriate
mechanisms, the Solar Rights Act of 1978 which addresses structural orientation
for solar access, and includes such concepts as solar easements, functional
landscaping, street layout, and architectural designs that reduce energy costs.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-16
2.2.6 Encourage, through the use of financial incentives, solar energy systems for the
heating of swimming pools.
2.2.7 Take full advantage of the CEQA process as a tool for evaluating energy use and
potential energy impacts, and for implementing appropriate energy conservation
measures.
2.2.8 Require the inclusion, where feasible, of provisions for energy efficient modes of
transportation and fixed facilities which establish public mass transit, bicycle,
equestrian, and pedestrian modes as desirable alternatives.
2.2.9 Work with appropriate Federal, State and private utility agencies to identify and
facilitate appropriate legislation for utility rate revisions that would provide
incentives for the conservation of energy by the shifting of energy usage to non-
peak hours.
2.2.10 Increase public awareness of energy conservation technology and practices by
the dissemination of information that describes energy conservation practices for
community members. This will encourage ongoing communication and the
generation of ideas, plans, and programs for the future development of Diamond
Bar as an energy efficient City.
Objective 2.3 Reduce overall local energy consumption by promoting efficient land use patterns which
reduce the amount of vehicular travel.
Strategies: 2.3.1 Land uses in the City will be planned to reduce vehicle miles traveled between
compatible and related uses, such as home-shopping, home-office, home-school,
etc.
(a) This will apply to mixed-use Planned Developments in particular when
planning and reviewing new land uses.
2.3.2 Design and implement a Citywide system of bikeways and pedestrian trails as
non-polluting circulation alternatives.
Objective 2.4 Cooperate with and encourage local education, governmental, and private organizations
in the development and use of new energy technologies that are deemed environmentally
safe.
Strategies: 2.4.1 Maintain open communication with other local, regional, State or Federal
agencies regarding the evaluation of current energy problems and state-of-the-
art technologies and practices.
2.4.2 Emphasize fuel efficiency and the use of alternative fuels in the acquisition and
use of City-owned vehicles and fleet vehicles of City franchisees; support
programs which would serve to enhance or encourage the use of public transit
systems.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-17
(a) Cooperate with the South Coast Air Quality Management Agency in the
development and local testing of new alternative fuels or other energy
programs.
2.4.3 Participate with local organizations on research and/or the development of
alternate energy sources, including cogeneration, photovoltaic, biomass, waste
to energy, wind, etc.
2.4.4 Investigate the potential for adding provisions in the Development Code to
require industrial and/or commercial projects to be sited to facilitate
photovoltaic and/or cogeneration units.
Objective 2.5 Minimize the environmental impacts of landfill disposal of solid wastes through an
aggressive public education and information campaign designed to promote a
comprehensive program of source reduction, recycling, composting, and household
hazardous waste reduction activities.
Strategies: 2.5.1 Continue to implement the Source Reduction and Recycling Element adopted
according to the guidelines established by State law and the California Integrated
Waste Management Board.
2.5.2 Develop and implement a Household Hazardous Waste Element according to
the guidelines of the California Integrated Waste Management Board.
Incorporate this element into the Resource Management Element of the General
Plan.
2.5.3 Reduce wasteful packaging of products sold in the City through educational and
technical assistance which emphasizes the reduction of non-recyclable products,
replacement of disposable materials with reusable materials, and the purchase of
repairable products.
2.5.4 Implement a mandatory Citywide recycling program including residential
curbside collection and voluntary on-site programs serving multi-family,
commercial and industrial generators.
2.5.5 Educate residential, commercial and industrial generators about source reduction
and recycling programs and encourage their participation by developing a
promotional campaign which informs them about diversion programs, identifies
opportunities for participation in such programs, and provides motivational
incentives to increase participation.
2.5.6 Require commercial and industrial generators to develop and implement a
source reduction and recycling plan tailored to their individual waste streams.
2.5.7 Promote the reduction of the amount of yard waste generated by public and
private residences through ongoing promotion of greenwaste by on-site
composting of leaves and other organic materials in a manner that is safe and
clean.
Diamond Bar General Plan Resource Management Element
July 25, 1995 III-18
2.5.8 Designate City held open space and public facilities as “green zones” and
conduct an aggressive pursuit of existing and potential City uses for compost
produced from locally generated yard waste such as park and median sites.
2.5.9 Increase public understanding of methods to reuse materials in their everyday
lives. Encourage the provision of educational materials on the environmental
damage of disposable products and materials.
2.5.10 Reduce the disposal of household hazardous wastes in landfills through
continued cooperation with the County Sanitation Districts and the Los Angeles
County Department of Public Works on implementation of a Countywide
household hazardous waste management program.
Objective 2.6 Pursuant to Government Code 65302 (d) and (e), the Conservation Element and the
Open Space Element will be prepared.
Strategies: 2.6.1 The Resource Management Plan will be developed in coordination with any
Countywide water agency plans in conjunction with County, District or City
agencies. This Resource Management Plan will cover:
• Reclamation of land and water
• Prevention control of pollution in stream and other waters
• Regulation of the use of land in stream channels
• Protection of watersheds
• Flood control
2.6.2 An Open Space Plan will be prepared to identify areas which will comply with
Government Code Section 65560 that encompasses the four principal categories:
Natural resources; managed production of resources; outdoor recreation; and
public health and safety.
• Identify open space land necessary to guarantee the availability of land
for preservation of plant and animal life, production of food, scenic
beauty, outdoor recreation and natural resources
• Discourage premature and unnecessary conversion of open space land to
urban uses
• Assure that the interests of all people are met in an orderly growth and
development of resources for the promotion of the general welfare and
protection of the public interest in open space land
IV. PUBLIC HEALTH
and SAFETY
ELEMENT
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 i
PUBLIC HEALTH AND SAFETY ELEMENT
TABLE OF CONTENTS
PAGE
A. INTRODUCTION.........................................................................................................IV-1
B. EXISTING CONDITIONS............................................................................................IV-2
C. PUBLIC HEALTH AND SAFETY ISSUES................................................................IV-7
D. PUBLIC HEALTH AND SAFETY GOALS OBJECTIVES, AND STRATEGIES....IV-9
LIST OF FIGURES
FIGURE PAGE
IV-1 Local Geologic and Seismic Hazards............................................................................IV-3
IV-2 Areas of Potential Flooding...........................................................................................IV-5
LIST OF TABLES
TABLE PAGE
IV-1 Noise Standards ...........................................................................................................IV-15
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Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-1
IV. PUBLIC HEALTH AND SAFETY ELEMENT
A. INTRODUCTION
The Public Health and Safety Element contains provisions that relate to the protection of life, health, and
property from natural hazards and man-made hazards. It is designed to identify areas where public and
private decisions on land use need to be sensitive to hazardous conditions caused by slope instability,
seismic activity, flood, fire, and wind.
State planning law requires cities and counties to identify hazardous conditions and to prepare and
implement policies to assure public health and safety. Section 65302(g) of the Government Code
describes these requirements (Safety Element) in the following terms:
“A safety element is for the protection of the community from any unreasonable risks associated -
with the effects of seismically induced surface rupture, ground shaking, ground failure, tsunami,
seiche, and dam failure; slope instability leading to mudslides and landslides, subsidence and
other geologic hazards known to the legislative body; flooding; and wildland and urban fires. The
safety element shall include, mapping of known seismic and other geologic hazards. It shall also
address: evacuation routes, peakload water supply requirements, and minimum road widths and
clearances around structures, as those items relate to identified fire and geologic hazards.”
In addition, adoption of a Noise Element has been a requirement of local General Plans since 1971.
Section 65302(h) 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...”
The Public Health and Safety Element provides the goals and strategies necessary to protect Diamond Bar
residents from the hazards associated with natural and man-made environments. The purpose of these
goals and strategies in this section is to incorporate safety considerations into the City's planning and
decision making process to reduce identifiable risks.
The City of Diamond Bar and its citizens must decide the degree of risk that is acceptable for various
natural and man-made hazards. Risks identified in existing development may be lowered to an acceptable
level by physical alteration, relocation or demolition, or a change in the use altogether. For new
development, the emphasis is to regulate construction so as to minimize identifiable risks to the extent
possible.
The Public Health and Safety Element addresses the following issues:
• Geology and Seismicity
• Flooding
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-2
• Fire Protection Services
• Crime and Protection Services
• Emergency Services and Facilities
• Hazardous Materials
• Air Quality
• Noise
B. EXISTING CONDITIONS
The following summarizes information presented in the City of Diamond Bar Master Environmental
Assessment.
1. Geology and Seismicity
Diamond Bar is located in a dynamic geological region, which is underlain by several thousand feet of
sediments which were laid down over the last 25 million years. Bedrock materials are not well
consolidated and consist of various sandstones, shales, and siltstones of the Puente formation, which is
represented by three major components or members: La Vida; Soquel; and Yorba. Stream-carried
(alluvial) materials are present in natural canyons while man-made fill is found in previously developed
areas. Local soils are mainly derived from weathering of the bedrock units.
There are existing historical and potential, unstable hillside areas in Diamond Bar.
Diamond Bar is also located in a part of Southern California which is a highly seismically active region
and where there are a number of major active faults. A discussion and map of regional geological hazards
are contained in the Master Environmental Assessment. The San Andreas Fault Zone, located 26 miles
northeast of the City, is considered to have the greatest potential to cause regional damage. However, the
Los Angeles County Engineer has estimated that four potentially active local faults (Whittier, San Jose,
Sierra Madre, and San Gabriel) have a higher potential for causing local damage. Several major faults are
located adjacent to the City. The Whittier Fault Zone passes just south of the City's Sphere of Influence,
while the Chino Fault passes within a mile of the City's eastern boundary. In addition, there are three
small inactive local faults within Diamond Bar: The Arnold Reservoir Fault, near Grand Avenue in the
northeast portion of the City; the Spadra Fault, located in the far portion of the City; and the Diamond Bar
Fault, located in the south-central portion of the City. A small inactive fault, the Tonner Canyon Fault is
located in the City's Sphere of Influence. Figure IV-1 identifies known faults and other local geologic
hazards.
2. Flooding
Runoff in the City is accommodated by three major natural drainages: San Jose Creek to the west;
Diamond Bar Creek to the southwest, and Brea Canyon Creek to the southwest. The only area of the City
with flooding problems, as identified by the Federal Emergency Management Agency Flood Insurance
Program, is along the Reed Canyon Channel at Brea Canyon Road and Lycoming Street. However, the
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-3
Figure IV-1 Local Geologic and Seismic Hazards
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-4
lands within the City of Industry adjacent to Diamond Bar, generally located west of the 57 Freeway from
Temple Avenue to Lemon Avenue, also have potential flooding problems. While most of the backbone
drainage system has already been installed by the County of Los Angeles, there are still a few links and
improvements that have not been constructed. The City presently lacks a master plan of drainage. The
Sphere of Influence is drained by Tonner Canyon Creek. This area presently has no major flood control
improvements and flooding can occur along the entire length of this natural stream channel. Figure IV-2
indicates areas where flooding poses potential problems.
3. Fire Protection Services
Diamond Bar faces a significant potential threat from wildland fires for the following reasons: It is
adjacent to large undisturbed natural areas to the east and south; it has many undeveloped hillsides and
canyons covered with native vegetation; many older homes have wood shingle or shake roofs; the state-
wide drought has killed, damaged or dried out much of the otherwise healthy natural, as well as
introduced, vegetation, and the area periodically experiences strong dry “Santa Ana” winds when other
fire conditions are high. Despite these conditions, the Insurance Service Organization (ISO) gives the
developed portions of the City a rating of 3, which is considered good for urbanized areas. The Sphere of
Influence area adjacent to Tonner Canyon does not presently have (or need), these same levels of
protection.
Fire protection services for the area are presently provided by the Los Angeles County Consolidated Fire
Protection District, which maintains three stations in or adjacent to the City. County stations 119, 120,
and 121 are fully equipped and staffed. Analysis of available service level data indicates that the City will
probably not need an additional fire station, although any significant development in the Sphere of
Influence area might require additional protection.
4. Crime and Protection Services
The level of major crime in Diamond Bar is presently half of that experienced in communities of
comparable size. The types of local crimes are typical of suburban communities in the Los Angeles
region, including vandalism, traffic accidents, and theft. Protection services are provided under contract
to the City by the Los Angeles County Sheriff's Department out of the Walnut/Diamond Bar Regional
Station. If emergency situations arise in which Diamond Bar units need assistance, additional units are
readily available from the San Dimas and Industry Station units. The City is presently served by 30
deputies and 18 patrol vehicles. The County maintains an average emergency response time of 4.5
minutes within the City: Diamond Bar will need additional protective services as it grows, although it
may not need additional facilities within the City limits. The Firestone Boy Scout Ranch within the
Sphere of Influence presently has private security.
5. Emergency Services and Facilities
The Diamond Bar area is served by a number of hospitals and related medical facilities within Los
Angeles, San Bernardino, and Orange counties. Although there is no Major treatment facility within
Diamond Bar, there are seventeen hospitals or major treatment centers within a 15 mile radius. The Los
Angeles County Consolidated Fire Protection District maintains paramedic service at station 119 just west
of the City, as well as at stations 61 and 118 in nearby Walnut. The county also contracts with several
local companies for ambulance service, and can also provide airborne evacuation. The region could also
face major emergencies or disasters, such as earthquakes, hazardous material spills, train accidents, high
winds, etc. The City has recently developed a response plan for major emergencies. Minimum road
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-5
Figure IV-2 Areas of Potential Flooding
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-6
widths and clearances around structures as related to emergency access and fire prevention are specified
in City Code. Emergency evacuation routes are identified in the City's Multi-Hazard Functional Plan,
with the SR57 and SR60 Freeways identified as the major routes and major surface streets as additional
routes.
6. Hazardous Materials
Hazardous materials presently create a potential threat to the City. The primary threat facing the City
would come from a major traffic or train accident involving spillage of hazardous or toxic materials.
There are industrial or other businesses within the City or in the nearby City of Industry that treat, handle,
or store hazardous materials. As the area continues to grow, the likelihood of an accident or the potential
for illegal dumping increases. The Los Angeles County consolidated Fire Protection District maintains
“Hazmat” Response Teams to handle emergencies involving these materials, but the City must deal with
the local implications of hazardous wastes. As per State law, the City has developed a “Household
Hazardous Waste Element”.
7. Air Quality
The entire south coast air basin, within which Diamond Bar is located, suffers from some of the worst air
quality in the nation. Pollutants are not only generated locally within the east San Gabriel Valley, but are
also transported downwind from the Los Angeles basin. The primary pollutants of concern are ozone
(oxidants) and nitrogen dioxide, which are mostly generated by vehicular exhaust. The number of first
stage smog alerts has decreased dramatically from the early part of the decade. However, local ozone
levels have still exceeded state standards on over 100 days during each of the past three years. Local
topography, climate, wind, and air movement patterns tend to concentrate air pollutants along the freeway
corridors and especially in the Diamond Bar area. Several local intersections, including Grand
Avenue/Diamond Bar Boulevard and Grand Avenue/Golden Springs Drive, experience significantly
elevated levels of air pollutants during peak driving hours.
8. Noise
The City of Diamond Bar is relatively quiet except for noise corridors created by traffic on major
roadways and freeways. Noise is typically measured in decibels on the A-weighted scale db(A) which
most closely resembles the range of human hearing. Community noise levels are often measured on the
Community Noise Equivalent Level, (CNEL) scale. Noise levels have been estimated along major
roadways within Diamond Bar based on traffic volumes and the physical configuration of streets. The
combined 57/60 Freeway corridor generates the most noise, producing a 65 CNEL contour onto adjacent
land uses approximately 1,379 feet wide. The 57 Freeway by itself, north of the 60 Freeway, has a much
smaller 65 CNEL corridor of only 759 feet. However, the 60 Freeway alone, both east and west of the 57
Freeway, generates a 65 CNEL noise corridor 1,015 feet wide. These figures mean that daily outdoor
noise levels in areas adjacent or proximate to the local freeways reach or exceed acceptable planning
noise standards.
In addition to noise produced by the freeways there are: several local roadways generating 65 CNEL
levels beyond the right-of-way. These include sections of Brea Canyon Road north of the 60 Freeway,
Golden Springs Drive east of. Lemon Avenue and west of Prospectors Road, Diamond Bar Boulevard
north of Golden Springs Drive, Grand Avenue west of Golden Springs Drive, Pathfinder Road east of the
57 Freeway, and Sunset Crossing Road west of the 57 Freeway.
Finally, the Union Pacific Railroad line along the westerly boundary of the City is a major contributor of
local noise as are infrequent urban sources such as dogs barking and aircraft overflights.
Diamond Bar General Plan Public Health and Safety Element
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C. PUBLIC HEALTH AND SAFETY ISSUES
1. Geology and Seismicity
Because of the high seismic and diverse geological conditions, there are moderate to high geological
constraints for development in Diamond Bar, especially in hillside areas.
ISSUE ANALYSIS: The City needs policies to protect existing and future residents from local
geologic and seismic-related hazards.
2. Flooding
There are no major identified threats from flooding within the City. However, there is no schedule at
present for the remaining improvements needed to complete the local drainage and flood control network.
In addition, the existing planned improvements are based on County plans for the area, and may not
reflect current projects or timing on the development of open land.
ISSUE ANALYSIS: The City needs policies to minimize the threat to its citizens from
flooding, and establish a schedule of improvements based on an updated
master plan of drainage. As part of these policies, spec standards for
protection from various size storms (10-, 25-, 50-, 100-, and 500-year)
are needed.
3. Fire Protection Services
A major fire represents a significant potential threat to local residents. In addition to the loss of structures
and life, a major fire could destroy valuable biological resources within the City or its Sphere of
Influence. As development continues in the interface between natural and developed areas, the threat of
fire also increases. The Los Angeles County Consolidated Fire Protection District currently provides
adequate service to the residents of Diamond Bar in terms of protection from the threat of fire. However,
the City may wish to pursue other administrative arrangements for financial or other reasons. As the City
grows, it may be necessary to provide additional equipment, personnel, or stations to continue adequate
service levels.
ISSUE ANALYSIS: The City needs policies emphasizing the importance of fire prevention,
protection, and public safety.
4. Crime and Protection Services
Although crime rates in the City are presently low, the threat of gang or other criminal activity creeping
into the community from neighboring urban areas could become a major issue. The City should take
appropriate action now to reduce and/or avoid the increase in local crime, such as urban design concepts
which help protect property and residents. The Los Angeles County Sheriff's Department presently
provides an adequate level of service to the community, as evidenced by the currently low crime rate.
As the City's population increases, there will be an increased need, for protective services. Additional
services may also be needed as urban crime may continue to spread to suburban areas. To combat this,
local community and neighborhood involvement will be needed to help prevent or observe and report
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-8
various criminal activities. Any significant development in the Sphere' of Influence would also require
additional protective services.
ISSUE ANALYSIS: The City needs policies to emphasize the importance of careful design
and community action to minimize criminal activity.
5. Emergency Services and Facilities
At present, there appears to be an adequate number and variety of medical facilities and programs
available to City residents. However, as a new City, Diamond Bar must assess its own desires regarding
the convenience of medical services and determine if or how it will encourage certain medical uses into
the City. Paramedic and ambulance services likewise appear to be adequate, although additional services
may be needed as the community grows. Development in the Sphere of Influence may require additional
medical or other emergency facilities. The provision of daily emergency services must also be
coordinated with a local plan for responding to regional disasters.
ISSUE ANALYSIS: The City needs to decide f any additional medical facilities are needed,
and if so, where and how should they be located to best serve local
residents. The City needs to implement the disaster preparedness plan
to respond to regional or local emergencies.
6. Hazardous Materials
Hazardous wastes will continue to be an important community concern. The potential for accidents
involving hazardous materials is of concern to local residents.
ISSUE ANALYSIS: The City should develop policies to clearly identify potential sources of
hazardous materials and how accidents or emergencies involving such
materials will be handled.
7. Air Quality
Air quality is still considered a major detractor to the quality of life in Diamond Bar; even though the vast
majority of it is generated elsewhere. While the City has little control over regional pollutants, it can take
a proactive position on this issue by stating its intent to minimize the generation of local air pollution. It
can also take advantage of the location of the South Coast Air Quality Management District (SCAQMD)
office in Diamond Bar to offer itself as a “testing laboratory” for programs to reduce air pollution, where
such programs could be safely undertaken, thus establishing Diamond Bar as a model City for innovation
in Southern California.
ISSUE ANALYSIS: The City should work cooperatively with local agencies to develop
innovative policies for reducing regional air pollution, in addition to
implementing the current programs of the South Coast Air Quality
Management Plan.
8. Noise
Noise is presently a problem for local residents along freeways and major roadways, generally only
during peak hours. However, noise problems will increase as traffic and population increase, especially
where development is built in areas that previously acted as buffers or barriers to local noise. As the
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-9
population of the City and region increases, there will also be an increase in infrequent urban noise
sources. While noise may not be a significant problem compared to other cities, a quiet environment is
typically a major factor in rural living, and more than likely contributes to the quality of life perceived in
Diamond Bar.
ISSUE ANALYSIS: Emphasizing its importance on quality of life, the City needs clear
policies on how it will keep noise, primarily from major roadways from
impacting existing, as well as future residents.
9. Urban Runoff Stormwater Discharge Permits
In recent years, the U.S. Environmental Protection Agency has recognized the potential for groundwater
damage to occur as the result of pollutants carried in runoff from urban areas. These pollutants include
oil, grease, and heavy metals that generally accumulate in roadways and parking areas, and are the result
of motor vehicle use. To resolve the problem, the EPA requires that municipal agencies acquire discharge
permits for urban areas similar to the permits issued for wastewater treatment plants. Los Angeles
County has received a discharge permit for urban runoff from the EPA. The City of Diamond Bar is a
“co-permittee”
ISSUE ANALYSIS: Development within the City of Diamond Bar will need to comply with
the provisions of the EPA urban stormwater discharge permit.
D. PUBLIC HEALTH AND SAFETY GOALS OBJECTIVES, AND STRATEGIES
“IT IS THE OVERALL GOAL OF THE PLAN TO PROVIDE A SAFE AND HEALTHY ENVIRONMENT
FOR THE RESIDENTS OF DIAMOND BAR. “
GOAL 1 “Consistent with the Vision Statement, create a secure public environment which
minimizes potential loss of life and property damage as well as social, economic, or
environmental disruption resulting from natural and manmade disasters.”
Objective 1.1 Minimize the potential loss of life, physical injury, and property damage from
seismic groundshaking and other geologic hazards.
Strategies: 1.1.1 Require the new emergency facilities including but not limited to fire stations,
paramedic services, police stations, hospitals, ambulance services, and
emergency operations centers be designed to withstand and remain in operation
following the maximum credible earthquake event.
1.1.2 As required by the Uniform Building Code, require site-specific geotechnical
investigation be performed to determine appropriate design parameters for
construction of public and private facilities in order minimize the effects of any
geologic and seismic hazard on such development.
1.1.3 Adopt a grading manual to supplement the City of Diamond Bar Grading Code
with detailed information regarding rules, interpretations, standard specifications,
procedures requirements, forms, and other information applicable to control
excavation, grading, and earthwork construction and provide guidelines for
preparation of geotechnical reports in the City.
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-10
Objective 1.2 Minimize the potential for loss of life, physical injury, property damage, public
health hazards, and nuisances from the effects of a 100-year storm and
associated flooding.
Strategies: 1.2.1 Where applicable, as a prerequisite to new development or the intensification of
existing development, ensure that a drainage study has been completed by a
qualified engineer, certifying that the proposed development will be adequately
protected, and that implementation of the development proposal will not create
new downstream flood hazards.
1.2.2 In coordination with the Los Angeles County Public Works. Department, develop
and maintain a master plan of drainage, including an inventory of existing
facilities, and present development plans, to adequately assess existing and future
flood control needs and improvements within Diamond Bar.
1.2.3 Prepare a capital improvement program for flood control improvements needed
to complete a master plan of drainage. This schedule will be coordinated with
improvement plans by the County and address funding and timing of prioritized
improvements.
Objective 1.3 Require that properties in and adjacent to wildland areas are reasonably
protected from wildland fire hazards without degrading the viability of natural
ecosystems, providing a balance between removal of flammable vegetation,
introduction of fire resistant vegetation, and preservation of natural vegetation.
Strategies: 1.3.1 Where development is proposed within areas potentially subject to wildland fire
hazards, ensure that the Consolidated Fire District has the opportunities to review
the proposal in terms of its vulnerability to fire hazard and its potential as a
source of fire. Ensure that Fire Department recommendations regarding
mitigation of fire hazard risks are addressed.
1.3.2 Require new development in areas subject to wildland fire to be adequately
protected in a manner which minimizes the destruction of natural vegetation.
Prioritize this balance as follows:
• Protection of existing developed areas, and areas currently approved for
development.
• Preservation of significant biological resources to the extent feasible
Objective 1.4 Require an adequate distribution of Tire stations equipment, and manpower, and
maintain a maximum five minute response time to all urban areas.
Strategies: 1.4.1 Work with the Los Angeles County Consolidated Fire District to establish a
funding mechanism which would ensure that cost of providing new facilities and
equipment, including paramedic services, to support new development is
assessed against the developments creating that need.
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-11
1.4.2 Where appropriate, support, increased protection levels from that provided by
the minimum fire standards included in the Uniform Building and Fire Codes
(UBC and UFC).
Objective 1.5 Minimize the risk and fear of crime through physical planning strategies. Create
a high level of public awareness and support for crime prevention.
Strategies: 1.5.1 Refer proposals for new development, where appropriate, and for the
intensification of existing development to the Sheriff's Department for review.
1.5.2 Promote the establishment of neighborhood watch and business watch programs
to encourage community participation in the patrol of neighborhood and business
areas, and to facilitate increased awareness of potential criminal activities.
Objective 1.6 Promote the provision of adequate medical and emergency services to Diamond
Bar residents.
Strategies: 1.6.1 Coordinate with appropriate agencies for the provision of evacuation and
ambulance services within acceptable service levels and response times.
1.6.2 Investigate the need and feasibility of locating a major medical facility within the
City of Diamond Bar.
Objective 1.7 Implement effective emergency preparedness and response programs.
Strategies: 1.7.1 Coordinate the City's disaster preparedness plans with the State Office of
Emergency Management, County, schools, and other neighboring jurisdictions,
and participate in the development of a regional system to respond to daily
emergencies and major catastrophies.
1.7 2 The City's disaster plan shall integrate community resources into municipal
emergency management, including a list of local resources such as personnel,
equipment, material, specialized medical and other training, and auxiliary
communications.
1.7.3 Provide areawide mutual aid agreements and communication links with adjacent
governmental authorities and other participating jurisdictions.
1.7.4 Disseminate public information regarding actions which residents and businesses
should take to minimize damage in a natural disaster, as well as actions which
would be taken to facilitate recovery from a natural disaster.
Objective 1.8 Protect life and property from the potential detrimental effects (short and long
term) of the transportation, storage, treatment, and disposal of hazardous
materials and wastes in the City.
Strategies: 1.8.1 Coordinate with the established Los Angeles County program for household
hazardous waste collection according to the provision of Section 41500 of the
Public Resources Code (see also the solid waste section of the Plan for Resource
Management for additional policies).
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-12
1.8.2 Coordinate emergency response personnel to respond to hazardous materials
incidents.
1.8.3 Require development to meet the requirements of the County's urban stormwater
discharge permit.
Objective 1.9 The City should seek to improve local and regional air quality by encouraging
ride, sharing, use of public transit, and other transportation demand
management techniques.
Strategies: 1.9.1 Promote the provision of non-polluting transportation alternatives such as a
Citywide system of bikeways and pedestrian sidewalks.
1.9.2 Work with the South Coast Air Quality Management District to establish a
program of District review and comment on major proposed development
projects within the City.
1.9.3 Implement the provisions of the South Coast Air Quality Management Plan;
review projects for consistency with the South Coast Air Quality Management
Plan.
1.9.4 Include trip reduction requirements consistent with SCAQMD Regulation XV
and the requirements of the Los Angeles County Congestion Management Plan
in the development code with the goal of reducing home-to-work trips by
facilitating and participating in the following programs:
• Incorporate design measures into new development and, where feasible, into
existing developments proposed for intensification, including preferential
parking areas for car and van pools, employee drop off areas, secure bicycle
parking areas, bus turnout areas, etc.
• Disseminate information to Diamond Bar residents regarding the advantages
of, and procedures involved in, ride sharing and public transit
1.9.5 Ensure that site designs facilitate rather than discourage pedestrian movement
between nearby uses.
1.9.6 Require grading plans to include appropriate and feasible measures to minimize
fugitive dust.
1.9.7 The City will cooperate with the South Coast Air Quality Management District
to be a “test facility” or a laboratory for testing new air pollution control
programs where such programs can be safely conducted at no expense to the
City or its residents.
1.9.8 The City will offer to local governmental agencies, education institutions, and
businesses the opportunity to test new technologies and/or programs designed to
reduce air pollution, either directly or indirectly.
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-13
Objective 1.10 Consider noise issues in land use planning and development permit processing to
require that noise generated by one use or facility does not adversely affect
adjacent uses or facilities.
Strategies: 1.10.1 Within identified 65dB CNEL noise contours, require that site-specific noise
studies be prepared to verify site-specific noise conditions and to ensure that
noise considerations are included in project review.
1.10.2 Within identified 65dB CNEL noise corridors, ensure that necessary reduction
measures are applied to meet adopted interior and exterior noise standards.
1.10.3 New construction, including additions and remodels exceeding 25% of original
floor area, shall not be permitted to cause the exterior CNEL level of surrounding
residential neighborhoods to exceed those limits stated in Table IV-1, or to
significantly, adversely affect the existing CNEL of those neighborhoods.
1.10.4 Natural noise barriers, such as hillsides, shall not be modified or removed
without evaluating noise impacts to surrounding residential neighborhoods.
1.10.5 Through the CEQA process, analyze new projects which might have a significant
impact on noise sensitive uses (projects are defined as actions having the
potential to unreasonably increase projected CNEL noise levels). Require
demonstrated empirical mitigation measures to ensure that adopted noise
standards within sensitive land use areas are not exceeded as the result of the
proposed project. Mitigation measures shall be verified by field measurements
after construction. Prior to occupancy, if the required level of mitigation is not
achieved, further corrective action will be required.
1.10.6 As part of the Development Code, adopt noise-related development standards.
1.10.7 Where possible, encourage reduction of existing noise problems within existing
development where adopted noise standards are being reached or exceeded. The
City shall demand that the State of California install noise attenuation facilities in
all noise sensitive areas impacted by County, State or Federal highways.
1.10.8 As part of future General Plan review, or every five years, the noise contour map
shall be updated.
1.10.9 Apply mitigation measures as needed to noise generators and receptors to ensure
that adopted noise standards are met and to protect land uses from excessive
noise impacts.
1.10.10 Locate land uses to buffer residential uses from noise and activity caused by non-
residential uses or streets or highways and site buildings to serve as a noise
buffer. Refer to the Land Use section to insure a smooth transition between
residential and non-residential uses.
1.10.11 Ensure that land uses are located so as to meet the following standards: (see
Table IV-1 Noise Standards). If new construction does proceed, a detailed
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-14
analysis of noise reduction requirements must be made and needed noise
insulation features included in design.
1.10.12 Where new development exceeds the standards outlined within Table IV-1, a
detailed analysis of noise reduction requirements must be made and needed noise
insulation features included in design.
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-15
Table IV-1
Noise Standards
Diamond Bar General Plan Public Health and Safety Element
July 25, 1995 IV-16
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V. CIRCULATION
ELEMENT
Diamond Bar General Plan Circulation Element
July 25, 1995 i
CIRCULATION ELEMENT
TABLE OF CONTENTS
PAGE
A. INTRODUCTION..........................................................................................................V-1
B. CIRCULATION SYSTEM.............................................................................................V-2
C. CIRCULATION ISSUES.............................................................................................V-17
D. GOALS, OBJECTIVES AND STRATEGIES.............................................................V-21
LIST OF FIGURES
FIGURE PAGE
V-1 Regional Circulation.......................................................................................................V-4
V-2 Circulation Element roadway System.............................................................................V-5
V-3 Intersection Level of Service........................................................................................V-11
V-4 Existing Designated Bicycle Routes.............................................................................V-14
V-5 Hiking and Equestrian Trails........................................................................................V-16
V-6 Designated Truck Routes..............................................................................................V-18
LIST OF TABLES
TABLE PAGE
V-I City of Diamond Bar Roadway Classification................................................................V-7
V-2 Daily Roadway Capacity Standards*..............................................................................V-9
V-3 Level of Service (LOS) Interpretation..........................................................................V-10
Diamond Bar General Plan Circulation Element
July 25, 1995 ii
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Diamond Bar General Plan Circulation Element
July 25, 1995 V-1
V. CIRCULATION ELEMENT
A. INTRODUCTION
The purpose of the Circulation Element is to define the transportation needs of the City and present a
comprehensive transportation plan to accommodate those needs. The focus of this plan element is the
identification and evaluation of local circulation needs of the City of Diamond Bar, balancing those needs
with regional demands and mandates. It has been developed to guide the orderly improvement of the
circulation system within the City in a manner which will protect the quality of life which is Diamond Bar
and in direct response to the City's Land Use Element.
The overall intent of the Circulation Element is to provide safe and efficient movement between homes
and jobs, stores, schools or parks within the City. Under State planning law, each city must develop and
adopt a comprehensive long-term general plan for the physical development of that city. The following is
a mandatory requirement relating to city transportation planning.
Government Code Section 65302(b): A circulation element consisting of the general location and
extent of existing and proposed major thoroughfares, transportation routes, terminals, and other local
public utilities and facilities, all correlated with the land use element of the plan.
This is the first Circulation Element prepared for the City of Diamond Bar. Although it is a new city, it is
not a newly developing city, but rather one that is largely built out. Many strategic decisions related to
transportation facilities (e.g., locations of roadways) were made at the County level prior to City
incorporation. This Circulation Element provides the first opportunity to evaluate how best to utilize these
facilities, from the perspective of the City of Diamond Bar, its residents, businesses and other users of
City services.
Five basic steps were involved in developing the Circulation Element. The first step consisted of
documenting existing conditions and assembling a factual database. The second step involved the
development and validation of a transportation model used to forecast future travel demand and travel
patterns within the City and the surrounding area. Step three entailed identification of problems,
opportunities and issues. The fourth step was the evaluation of alternative improvement scenarios. The
fifth and final step comprised the definition and refinement of the Circulation Element
The resulting document is organized into the following sections with each of the above components of the
circulation system being discussed, where appropriate, therein.
• Circulation System
• Major Circulation Issues
• Goals, Objectives and Strategies
Diamond Bar General Plan Circulation Element
July 25, 1995 V-2
Technical Appendices to the Master Environmental Assessment document support this section and
contain additional details and analysis of existing and future conditions, travel forecast model
documentation, and the Congestion Management Plan.
The Circulation Element also has direct relationship with the Housing, Resource Management, Public
Management, Public Health and Safety and Public Services and Facilities Elements.
B. CIRCULATION SYSTEM
The components of the circulation system in the City of Diamond Bar include the following:
• Streets and Highways
• Transit and Paratransit Services
• Railroads
• Bicycle, Hiking and Equestrian Facilities
• Aviation
• Goods Movement
This section describes each of the components, discusses operating conditions and evaluates the adequacy
of the component.
1. Streets and Highways
a. Functional Classification, definitions and terms
The two major considerations in classifying the City's street network functionally are access to adjacent
properties and movement of persons and goods into and through the City. City streets are classified by the
relative importance of these two functions assigned to them. The classification of streets is essentially a
determination of the degree to which access functions are to be emphasized at the cost of the efficiency of
movement or discouraged to improve the movement function. The design and operation of each street,
therefore, depends upon the importance placed on each of these functions. For example, streets designed
to carry large volumes of vehicles into and through the City have more lanes, higher speed limits, and
fewer driveways, while residential streets have fewer lanes, lower speed limits, and more driveways to
provide access to fronting properties.
The functional classification system allows the residents and elected officials to identify preferred
characteristics of each street. If observed characteristics of any street change from the functional
classification, then actions can be taken to return the street to its originally intended use or to change the
designation classification. For example, if traffic volumes and speeds on a residential street exceed
expected levels, then measures can be implemented which are designed to lower traffic volumes and
reduce speeds.
Under the Circulation Element of the County of Los Angeles, roadways within Diamond Bar were
categorized into four functional classification types:
Diamond Bar General Plan Circulation Element
July 25, 1995 V-3
• Freeways
• Arterial Streets (Major and Secondary)
• Collector Streets (Business and Residential)
• Local Residential Streets
The City has adopted these functional classifications for its roadway network. Figure V-1 depicts the
regional roadway system as it presently exists in the City.
Freeways generally provide inter-regional access. Their primary function is to move vehicles through or
around the City, thus, there is not access to adjacent land, and limited access to arterial streets. Freeways
contain anywhere from 4 to 12 lanes with recommended design volumes from 80,000 to 210,000 vehicles
per day.
Arterial streets carry the majority of traffic entering or traveling through the City. A “major” arterial has
either four or six lanes for through traffic and may contain additional lanes to accommodate turning
movements, parking and bicycle traffic, all within a right-of-way of 100-120 feet. A “secondary” arterial
serves the same function as a major arterial, but has four lanes for through traffic and may contain
additional lanes to accommodate turning movements, parking and bicycle traffic, all within a right-of-way
of 60-100 feet. The desired maximum roadway capacity on arterial averages from 30,000 to 45,000
vehicles per day depending on number of lanes, type and width of directional separation, presence of on-
street parking, configuration and frequency of access to adjacent land uses, and intersection
configurations.
Arterials serve two primary functions: To move vehicles into and through the City, and to serve adjacent
commercial land uses. Driveways and other curb cuts along arterial are generally designed to minimize
disruption to traffic flow.
Collector Streets are intended to carry traffic between the arterial street network and local streets or
directly from the access drives of higher intensity land uses.
Collector Streets serve business or residential land and are generally two or four lane roadways. The
desired roadway capacity on a collector street can average up to 20,000 vehicles per day while providing
Level of Service (LOS) C.
Local residential streets are designed to serve adjacent residential land uses only. They allow access to
residential driveways and often provide parking for the neighborhood. They are not intended to serve
through traffic traveling from one street to another, but solely local traffic. The desired roadway capacity
on a residential street should not exceed about 2,500 vehicles per day and 200-300 vehicles per hour. The
maximum residential traffic volume which is acceptable to persons living along a street may vary from
one street to another depending upon roadway width, type of dwelling units (i.e., high density apartments
versus single-family homes), presence of schools and other factors. The maximum volume of 2,500 is,
therefore, to be used as a guide only, and sensitivity to the neighborhood and its impact needs to be
carefully considered.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-4
Figure V-1 Regional Circulation
Diamond Bar General Plan Circulation Element
July 25, 1995 V-5
Figure V-2 Circulation Element Roadway System
Diamond Bar General Plan Circulation Element
July 25, 1995 V-6
Local residential streets include those streets predominantly residential in terms of adjacent property use,
and are intended to retain a residential character. They are typically not designated in the General Plan
Circulation Element.
Table V-1 identifies roadway classifications for key roadways in the City along with right-of-way
guidelines. Typical street sections are maintained as part of the City's design guidelines. Current typical
street sections are included in the technical appendices.
b. Level of Service Standards
Level of service standards define the desirable traffic volumes on City streets in relation to the capacity of
those streets. The City has utilized level of service standards in the traffic analysis work for the General
Plan, and these are summarized in the EIR. The City should continue to use such standards, maintaining
and updating them when necessary to be consistent with current prevailing standards in the region and
requirement such as the statewide Congestion Management Program. Table V-2 presents the average
daily volumes of various roadway configurations for different levels of service.
c. Roadway Systems
The efficiency of a roadway's operation is generally evaluated in the industry by volume-to-capacity
ratios. This ratio compares the Average Daily Traffic volume to the roadway's capacity. Levels of Service
(LOS) are identified based on the calculated ratio. Table V-3 provides a description of the various levels
of service to be used as the City's guidelines for analyzing the efficiency of street operation.
Specific information regarding:
• Current levels of service
• Estimated existing and future average daily volumes by street segment
• AM/PM peak hour traffic levels of service by street segment
• Map of signalized intersections
• A description of the methodology and data used to establish baseline information and current
conditions is contained in the Master Environmental Assessment and technical attachments.
A major concern of the City of Diamond Bar is the operating efficiency of its streets. Based upon an
analysis performed in 1991, traffic projections for the future (year 2010) indicate that up to 26 local street
segments may experience a level of service of E or F. This undesirable condition is the result of the
intrusion of regional traffic through Diamond Bar.
The City proposes to proactively pursue activities which will enhance the use of its infrastructure for
Diamond Bar residents In addition, the City will work with neighboring jurisdictions to mitigate their
effects on the local street system due to the intrusion of regional traffic.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-7
Table V-I
City of Diamond Bar Roadway Classification
Diamond Bar General Plan Circulation Element
July 25, 1995 V-8
d. Transportation Corridors
A key issue related to traffic circulation is how current street infrastructures will be used and what future
improvements may be considered to mitigate traffic congestion.
To this end, the City of Diamond Bar intends to:
• Monitor, coordinate, identify and advocate improvements or modifications to the existing
infrastructure which will provide for the best use of our roadway-system for the movement of
traffic.
• Encourage and initiate ongoing efforts to work with neighboring cities to analyze, assess and
evaluate alternate by-pass corridors through such areas as Carbon, Soquel and Tonner Canyon.
The City also believes that if a by-pass corridor is identified for a roadway, it should be considered using
environmentally sensitive methods of evaluation.
e. Environmentally Sensitive Transportation Corridor
An environmentally sensitive transportation corridor is a transportation facility defined by characteristics
that cause the facility to have minimal impact to the environment and adjacent ecosystem. It also meets
the general prerequisites of being able to, allow for movements of people and goods in a safe and efficient
manner. These characteristics should include but not be limits to the following:
topographic — the corridor should blend with the natural terrain as much as possible to reduce
grading and movement of earth. Curves and contours of the natural terrain should be reflected in
design of the corridor. This goal must necessarily be balanced with providing safe corridor
geometry for the modes of travel that will use it.
hydrology — positive drainage control will be developed as part of the corridor design to provide
for capture and transmission of runoff from the facility to an appropriate storm drainage facility.
This goal is to control foreign and potentially incompatible fluids and particles from entering the
adjacent ecosystem.
air quality — street sweeping/cleaning shall be programmed into maintenance operations to
prevent buildup of dirt and dust on the corridor travel surface. This goal will serve to reduce the
amount of airborne particulates which could otherwise enter the adjacent ecosystem. Alternative
fuel vehicles and small vehicles should be encouraged rather than trucks to further improve air
quality along the corridor.
noise – to the extent possible, modes of travel should be encouraged which have reduced sound
characteristics. In addition, natural barriers to sound created by the corridor should be developed
and implemented to reduce sound intrusion into the adjacent ecosystem. Consider controlled
speed limits to reduce noise impacts.
corridor – a corridor should be defined as a route that encourages movement of people in a
manner that encourages multimodal uses such as buses, trolleys and shuttles; discourages single
occupant vehicle trips. Movement of goods within this corridor should be evaluated in terms of
not detracting from the basic goal of maximizing movement of people in high occupancy
vehicles. Restriction on vehicle type and weight may be considered as part of the corridor.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-9
Creative traffic management techniques should be encouraged (such as reversible lane operation)
to take best advantage of roadway cross section and minimize impacts to the corridor area.
biological habitat — replant and maintain natural plant species to the extent possible along the
corridor where grading has altered the natural landscape. Similarly, provide frequent game
crossings to permit natural migratory paths to be maintained. Consider designation of the
corridor for daylight use only.
aesthetic – views from the corridor should reinforce the feeling in the traveler that they are in an
environmentally sensitive area. Similarly, views of the corridor from adjacent properties should
reinforce the feeling that the corridor is a natural part of the landscape. Corridor structures, as
necessary, should be a natural part of the terrain.
By nature of the location of the by-pass corridor around the SEA 15, the corridor should be for
regional traffic and should not encourage local access for adjacent development except as
required by safety and emergency access requirements. Construction activity should be limited
to the right-of-way envelope. End points of the corridor would incorporate value criteria.
An environmentally sensitive transportation corridor does not presume to specify the type of vehicles that
will utilize the facility. Rather, it should encourage and foster high occupancy, clean operation, modes
that are integrated with the corridor. Planning efforts should look to the future and anticipate technologies
that will emerge and contribute to development of a corridor that meets the growing travel demands of the
region and maintains precious natural resources.
Table V-2
Daily Roadway Capacity Standards*
Diamond Bar General Plan Circulation Element
July 25, 1995 V-10
Table V-3
Level of Service (LOS) Interpretation
Diamond Bar General Plan Circulation Element
July 25, 1995 V-11
Figure V-3 Intersection Level of Service
Diamond Bar General Plan Circulation Element
July 25, 1995 V-12
2. Transit and Paratransit Services
Both fixed route transit and Paratransit service operate within the City of Diamond Bar. Fixed route
transit services are typically buslines, which operate on regular schedules along a set route, stopping at
predefined bus stops: Fixed route service can be either local (intracity) or regional (intercity). Paratransit
services, more commonly referred to as Dial-a-Cab, are demand responsive services which provide rides
to passengers upon an individual request basis. Although they operate within a defined service area, they
do not operate on fixed routes or schedules. Paratransit service typically serve transit dependent persons
such as the elderly and handicapped. They often serve major destinations such as hospitals and medical
facilities but may also take passengers to local destinations such as neighborhood shopping centers.
a. Transit Services:
Public bus transit service is provided to the City of Diamond Bar by the Metropolitan
Transportation Authority and Foothill Transit and Orange County Transportation Authority
(OCTA).
Four fixed route transit lines serve the City of Diamond Bar. Foothill Transit Route 482 and
MTA Route 490 originate and terminate outside the city limits. Two express routes
originating at the Park and Ride lot at Diamond Bar Boulevard/60 Freeway interchange
operate during peak hours Monday through Friday. Foothill Transit Express Route 495 picks
up passengers on Golden Springs Drive/Colima Road to the Puente Hills Mall, then travels the
freeways to downtown Los Angeles. OCTA operates an express route from the same Park and
Ride via Cal State Fullerton, City Drive and the Orange County Court House in Santa Ana.
Additionally, three Foothill Transit lines provide intermodal connections at the Industry
Metrolink Station just north of the City's boundary on Brea Canyon Road. They are Route 482
(Colima Road), Route 276 (Gale Avenue) and Route 179 (Amar Road).
b. Paratransit Services:
Demand responsive transit service is provided to the City of Diamond Bar by the jointly
sponsored Los Angeles County and City of Diamond Bar Paratransit Service. This Dial-a-Cab
service provides transportation to handicapped persons and senior citizens within not only the
City of Diamond Bar, but portions of the surrounding area. Transportation is provided within
ten miles of the city limits at a reduced rate.
3. Railroad Lines
There are currently no passenger rail facilities in operation within the City of Diamond Bar. The nearest
Amtrak-facilities are located in Pomona and Fullerton. The Pomona Amtrak stop, which serves the Sunset
Limited Route, is located at 156 W. Commercial St. and is approximately nine miles northeast of
Diamond Bar. The Fullerton Amtrak station, which serves the Southwest Chief and San Diegan lines,
with intermodal (bus) connections to other Amtrak lines, is located at the corner of Santa Fe and Harbor
Boulevard and is approximately 13 miles to the southwest.
Diamond Bar is served by a Metrolink commuter rail station recently implemented along the Union
Pacific Railroad at Brea Canyon Road, just north of State Route 60.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-13
The Union Pacific Railroad is the only freight rail line which serves the City of Diamond Bar. The line
lies along the City's northwestern boundary with the City of Industry, and serves the industrial areas north
of Walnut Drive and Lycoming Street.
4. Bicycle, Hiking and Equestrian Trails
a. Bicycle Routes
There are three different classes of bikeways which are commonly recognized. A
definition of each bikeway class is presented below:
Class I Bikeway (Bike Path) - A completely separated right-of-way for the exclusive
use of bicycles (and sometimes pedestrians). Cross-flow is minimized by limiting access
to designated points.
Class II Bikeway (Bike Lane) - Routes designated by separately striped lanes and signs
along streets or highways. They provide restricted one-way travel for bicycles, although
motor vehicles are sometimes permitted to use the bike lane to make turns and to park.
Class III Bikeway (Bike Route) - Roadways in which the travel lanes are shared by
motor vehicles and bicycles whose route is designated by signs only. This type of
bikeway does not provide cyclists with increased privileges, but rather, informs motorists
of the cycling route.
Figure V-4 shows Existing Designated Bicycle Routes in the City of Diamond Bar.
The City currently has two designated bikeways along the length of Diamond Bar Boulevard and along
the length of Golden Springs Drive from Brea Canyon Road to the northerly city limit. Diamond Bar
Boulevard and Golden Springs Drive west of Diamond Bar Boulevard contain Class II bike lanes. The
width of the bike lanes vary from 12 feet throughout most of the roadway to three feet at a few locations
with narrower curb-to-curb widths. Most signalized intersection bike lane approaches are striped to permit
right turns by motor vehicles. Parking is not permitted within the bike lanes except on Golden Springs
Drive near Brea Canyon Road, and on the northbound lane of Diamond Bar Boulevard between
Montefino Avenue and Grand Avenue. Golden Springs Drive north of Diamond Bar Boulevard is
designated a Class III bike route on both sides of the roadway. An additional bikeway is marked, though
not designated by City Resolution, along both sides of Brea Canyon Road between Pathfinder Road and
Golden Springs Drive.
There are currently no Class I bikeways within the City of Diamond Bar.
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 from 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 Golden
Springs Drive (into Rowland Heights), east along Grand Avenue (City of Chino Hills), and south along
Chino Hills Parkway (City of Chino Hills).
Diamond Bar General Plan Circulation Element
July 25, 1995 V-14
Figure V-4 Existing Designated Bicycle Routes
Diamond Bar General Plan Circulation Element
July 25, 1995 V-15
b. Equestrian and Hiking Trails
There is currently one official equestrian and hiking trail available to the public within the City of
Diamond Bar. This trail, through the City, is part of a more extensive trail system owned and maintained
by the County of Los Angeles.
The Skyline Trails Extension, unofficially called the Schabarum Trail roughly parallels the City's
southern and eastern boundaries with unincorporated sections of Los Angeles and San Bernardino
Counties as it winds through the hills from Brea Canyon Road to Grand Avenue. The trail originates at
Schabarum Park to the west, where it interconnects with the Skyline Trail. The Skyline Trail, in turn,
interconnects with a vast system of equestrian trails to the north and west spreading throughout most of
Los Angeles County. To the east of Schabarum Park, the trail traverses Rowland Heights, then exits under
Brea Canyon Road and the Orange Freeway where it approaches the southern City limits of Diamond Bar
to the east of Brea Canyon Road. The trail then travels near the edge of the Firestone Boy Scout
Reservation near the northern slopes of Tonner Canyon. As the trail turns northeast, it roughly follows the
City boundary, just inside of the City limits. The trail turns east and follows the City boundary just
outside the City limits, and again turning northerly, portions of the trail are within and portions are
outside the City. The trail terminates at Grand Avenue, where the Summit Ridge Park Connector Trail
will allow access to, Summit Ridge Parks to the north of Grand Avenue within Diamond Bar. There are
also a series of three spur trails which the County has planned to connect with the Skyline Trails
Extension Trail. These three trails, collectively known as the Skyline Trails Connections, all lie outside of
the City of Diamond Bar.
Figure V-5 shows hiking and equestrian trails in the City of Diamond Bar.
5. Aviation
There are no aviation facilities located within the City of Diamond Bar. Passenger air carrier and air cargo
facilities are located at Ontario International Airport located 15 miles to the east. The closest general
aviation airports are Brackett Field in La Verne, approximately nine miles to the north; and Chino Airport
in the City of Chino, approximately 11 miles to the east.
Because Diamond Bar is under flight paths from both Ontario and Los Angeles International Airports,
and proximity to major freeways tends to increase the number of helicopter overflights, the City should
remain vigilant to air traffic increases and seek regulations to relieve noise and air pollution.
6. Goods Movement
Goods movement within the City of Diamond Bar occurs primarily through the use of trucks. The City
has established a designated truck route plan. Truck routes direct heavy truck traffic onto arterial and
collector facilities and away from local (residential) streets. This plan helps control noise and air pollution
in residential areas of the City and protects local streets' from significant surface damage that might result
from heavy truck traffic.
North of the combined section of the Orange (57)/Pomona (60) Freeway it is necessary for freeway traffic
to exit onto Diamond Bar Boulevard when traveling southbound on the Orange Freeway en route to the
eastbound Pomona Freeway; and westbound Pomona Freeway traffic bound for the northbound Orange
Freeway. The section of Diamond Bar Boulevard between the eastbound Pomona Freeway ramps and the
northbound Orange Freeway ramps to the north, and Sunset Crossing Road between Diamond Bar
Boulevard and the southbound Orange Freeway ramps are designated truck routes.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-16
Figure V-5 Hiking and Equestrian Trails
Diamond Bar General Plan Circulation Element
July 25, 1995 V-17
To enable access to the heavy industrial areas of the City of Industry and the City of Diamond Bar north
of Lycoming Street, truck routes are designated in western Diamond Bar along Golden Springs Drive
between Lemon Avenue and Brea Canyon Road, along both Brea Canyon Road and Lemon Avenue north
of Golden Springs Drive, and along Walnut Drive.
Entrances into the City notify drivers of a five-ton weight restriction for trucks within the City (except for
designated truck routes), in addition to parking restrictions which limit commercial vehicles over five tons
to 30 minutes.
The General Plan Designated Truck Routes are illustrated in Figure V-6.
C. CIRCULATION ISSUES
The following significant issues concerning circulation are not necessarily listed in order of priority.
1. Future Development in Diamond Bar
The Diamond Bar General Plan provides for an additional 1,115 dwelling units, as well as additional
commercial office and business park uses.
ISSUE ANALYSIS: The City needs policies to address impacts to all streets in Diamond
Bar and to maintain or improve roadway level-of-service standards.
2. Projected Growth in the Region
In addition to increases in traffic attributable to growth and development within the City of Diamond Bar
itself, the City will be impacted by future growth and development in surrounding communities and the
region. Increased traffic in the region will impact Diamond Bar through increased traffic volumes along
the regional transportation facilities including Routes 57 and 60 and Grande Avenue.
ISSUE ANALYSIS: The City needs policies to address impacts to all streets in Diamond
Bar and to maintain or improve roadway level-of-service standards.
3. Future Roadway System Within Diamond Bar
Many of the roadway facilities within Diamond Bare are projected to carry volumes of traffic at or in
excess of recommended daily capacity by the year 2010. At present, a significant amount of the traffic is
regional traffic with neither origin nor destination within the City. Examples are as follows:
Diamond Bar Boulevard - Average daily traffic volumes along Diamond Bar Boulevard immediately
south of Grand Avenue are projected to be double the desirable volumes for a four-lane roadway. South
of Grand Avenue to Brea Canyon Road, forecast daily volume along Diamond Bar Boulevard exceed
recommended carrying capacity. North of Sunset Crossing, traffic volumes along Diamond Bar
Boulevard are projected to be within the carrying capacity pf a four-lane roadway.
Golden Springs Drive - Year 2010 traffic volumes along Golden Springs Drive west of Brea Canyon
Road are projected to exceed the desirable maximum volumes for this four-lane roadway. From east of
Lemon Avenue to the City of Diamond Bar boundary, Golden Springs Drive is forecast to carry traffic at
or slightly below the recommended carrying capacity for a four-lane roadway.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-18
Figure V-6 Designated Truck Routes
Diamond Bar General Plan Circulation Element
July 25, 1995 V-19
The portion of Golden Springs Drive east of Grand Avenue is not a divided roadway and forecast traffic
volumes along this segment would exceed capacity.
Grand Avenue - Year 2010 traffic volume forecasts along the entire length of Grand Avenue within the
City of Diamond Bar are estimated to be in excess of the desirable maximum volumes for a four-lane
divided roadway.
Brea Canyon Road - The section of Brea Canyon Road from Golden Springs Drive to Washington Street
is projected to carry traffic volumes requiring arterial capacity.
Routes 57 and 60 - Both the Pomona Freeway (SR60) and the Orange Freeway (SR57) are forecast to
carry traffic volumes significantly in excess of their capacity. This will result in continued congestion
along these facilities with spillover onto City streets as motorists seek less congested alternatives.
ISSUE ANALYSIS: The City needs to establish roadway classifications and standards
for dedication and roadway improvement for the principal streets in
the City.
4. The Development of an Alternative Travel Corridor Around the City of Diamond
Bar
With significant development planned for the Chino Hills area, both Diamond Bar Boulevard and Grand
Avenue are expected to carry larger through traffic volumes from SR57 than at present into San
Bernardino County. Alternative routes to the south would help relieve future congestion along these and
other Arterials within the City of Diamond Bar. However, the location of an alternative travel corridor
must consider its potential environmental and growth-inducing impacts. Under these circumstances, it
will be prudent for the City to consider the option of a by-pass corridor. Studies of such a facility indicate
that should forecasted development and freeway improvements occur, a by-pass corridor will provide
substantial relief to the key streets in Diamond Bar. Therefore, it will be the policy of the City to:
• not wait until need for the by-pass Corridor is demonstrated, but proactively monitor signs for
the need so that timely planning and environmental steps can be taken;
• explore regional options for transportation improvements prior to initiating development of a
regional. by-pass corridor;
• seek cooperation of adjoining jurisdictions in managing growth and assigning responsibility
for infrastructure improvements to support that growth; and
• establish criteria under which a by-pass corridor would be considered, designed, constructed,
and, utilized.
ISSUE ANALYSIS: There is a need to consider a by-pass roadway around the City of
Diamond Bar to discourage regional traffic from using the City's local
streets for cut-through purposes only. This is of regional concern and
involves multiple jurisdictions. It is important for the City to take the
lead in assuring that any proposed project directly benefits Diamond Bar
residents and achieves the goals of this General Plan.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-20
5. Maintaining Grand Avenue's Current Traffic Carrying Capacity
Grand Avenue is a major arterial and provides a convenient alternative as a regional arterial, carrying
traffic to and from Route 57/60.
ISSUE ANALYSIS: The City will continue to monitor the effectiveness of Grand Avenue in
serving its local needs while maintaining its current traffic-carrying
capacity within the existing right-of-way. Ongoing efforts include:
• Optimizing signal synchronization;
• Encouraging projects to improve interchange at Route 57/60; and
• Providing turnout lanes, where beneficial.
6. Increase the Effectiveness of State Routes 57 and 60 to Discourage Through
Regional Traffic Use of Diamond Bar Streets
It is desirable to reduce the use of Diamond Bar streets by regional traffic.
ISSUE ANALYSIS: One of the most feasible approaches the City can take to reduce regional
traffic on Diamond Bar Boulevard is to work with Caltrans to improve
conditions on State Route 57 and 60. Possible improvements include:
• Upgrade the SR57/60 interchange to eliminate undue at-grade conflicts weaving maneuvers
and adding lanes or frontage roads between key interchanges;
• Provide HOV and connector lanes on both SR57 and SR60; and
• Provide truck climbing lanes where appropriate.
7. Surrounding Roadway Systems Impacting the City
It is also recognized that various roadway and street improvements are proposed or presently under
construction in neighboring communities or by other agencies which may impact the City of Diamond
Bar's transportation plans.
ISSUE ANALYSIS: Certain projects either planned or under construction have been
identified which may impact traffic circulation in the City.
These projects include but are not limited to:
• Completion of Route 30
• Upgrade of SR71 to freeway standards
• Improve the capacity of Interstate 10 (San Bernardino Freeway), State Route 60 (Pomona
Freeway) and State route 142 (Carbon Canyon Road)
Diamond Bar General Plan Circulation Element
July 25, 1995 V-21
• Completion of the High Occupancy Vehicle (HOV) System on Interstate 10, Route 60, and
State route 57 from the San Bernardino and Orange County lines to Highway 101.
8. Maintain the Cul-de-Sacs of Sunset Crossing Road, Beaverhead Drive, Washington
Street and Lycoming Street at the City's Boundaries.
Sunset Crossing Road is presently a four-lane roadway providing access to/from a residential area of
northwest Diamond Bar. Sunset Crossing Road west of Route 57 has an interchange with southbound
Route 57, extends westerly and terminates east of the City limits adjacent to a park and Little League
field. The County of Los Angeles Highway Plan assumes Sunset Crossing Road is to be extended
southwesterly, through the City of Industry to a connection with Washington Street or in the vicinity. The
City of Industry is considering the development of the area beyond the westerly terminous of Sunset
Crossing Road, Beaverhead Drive, Washington Street and Lycoming Street with industrial uses and a
waste-to-rail materials recovery facility. The proposed development of industrial uses would significantly
increase the volume of traffic along these residential streets and introduce a significant number of trucks
into these residential neighborhoods.
ISSUE ANALYSIS: The City should implement strong measures to maintain the integrity of
residential neighborhoods.
D. GOALS, OBJECTIVES AND STRATEGIES
“IT IS THE OVERALL GOAL OF THE PLAN TO PROVIDE A SAFE, ADEQUATE AND
ENVIRONMENTALLY SENSITIVE TRANSPORTATION SYSTEM TO MEET THE
CIRCULATION NEEDS OF THE CITIZENS OF DIAMOND BAR.”
GOAL 1 “Consistent with the Vision Statement, enhance the environment of the City’s street
network. Work toward improving the problems presented by the intrusion of regionally
oriented commuter traffic through the City and into residential neighborhoods. Consider
programs to reinforce the regional transportation and circulation system to adequately
accommodate regional needs.”
Objective 1.1 Participate in local and regional transportation related planning and decision-
making.
Strategies: 1.1.1 Preclude the connection of roadways from adjacent jurisdictions into the City
unless demonstrable benefits to Diamond Bar residents and businesses are
indicated.
1.1.2 In reviewing transportation improvements, maintain a clear distinction between
local and regional objectives.
1.1.3 Ensure the opportunity for public comment on major changes in operational
characteristics of the circulation system.
1.1.4 Initiate regional traffic mitigation efforts with the cities of Brea and Chino Hills
by forming a task force, assisted by technical personnel to evaluate alternative
Diamond Bar General Plan Circulation Element
July 25, 1995 V-22
travel corridors through the easterly portion of the Sphere of Influence. Efforts
will generally include:
(a) Recognition of environmentally sensitive areas;
(b) Identification of the types of environmentally sensitive roadways which
will be considered;
(c) Avoid any roadway within the Significant Ecological Area -(SEA15).
(d) Land use constraints and development limitations which may be in
place or imposed;
(e) Contribution to congestion based on development and anticipated
growth projections;
(f) Prioritization of alternatives based on available documentation, studies,
reports, etc.;
(g) Identification of alternative funding sources for studies, design,
construction and maintenance such as, but not limited to:
(1) Los Angeles; Orange and San Bernardino Counties;
(2) State of California;
(3) Federal Government;
(4) Local funding such as Prop C or redevelopment funds;
(5) Development; and
(6) Private.
(h) Identification and formulation of a short and long range plan of action to
address the by-pass issue.
1.1.5 Work with neighboring communities to encourage the ongoing efforts to
complete existing projects and possible improvements to existing infrastructures
such as:
(a) Completion of SR30;
(b) Upgrade of SR71 to freeway standards;
(c) Additional lanes on SR60; and
(d) Increasing the roadway capacity of SR142, Carbon Canyon Road.
1.1.6 Continue to seek support for Regional State Transportation Improvement
Program (RSTIP) projects as proposed by the City of Diamond Bar such as:
(a) Encourage modification of the SR57/SR60 interchange;
(b) Support construction of HOV lanes on SR60, from SR57 north to San
Bernardino County;
(c) Support construction of HOV lanes on SR60, from Brea Canyon Road
to SR57 north;
(d) Support construction of HOV lanes on SR57, from Orange County to
SR60; and
(e) Pursue additional Park and Ride facilities east of the City.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-23
1.1.7 Encourage Orange and San Bernardino Counties to fund and construct an
environmentally sensitive transportation corridor through Soquel Canyon and/or
Carbon Canyon.
1.1.8 Coordinate the use of land use policies from neighboring communities and
incorporate all existing traffic data including improvements and proposal for the
regional circulation system.
1.1.9 Encourage improvements to regional routes and arterial streets to be sensitive to
environmentally, aesthetic and noise concerns and provide adequate buffers to
adjacent land uses.
1.1.10 Through the use of the provisions of the California Health and Safety Code,
Division 24, Parts 1, 1.5 and 1.7, pursue a comprehensive and, if possible,
coordinated effort with the City of Industry and the State of California to upgrade
the one mile stretch of freeway carrying the SR57 and SR60; and upgrade the
interchanges of Brea Canyon Road and the SR60; Grand Avenue and the
SR57/60; and Diamond Bar Boulevard at the SR57 north and south; and the
widening of Golden Springs Drive.
Objective 1.2 Balance the need for optimum traffic flow on City Arterials within economic
realities, environmental, and aesthetic considerations.
Strategies: 1.2.1 Prepare programs for traffic control measures including, but not limited to,
additional stop signs at problem intersections, timing of signals and regulation of
speed limits.
1.2.2 Maintain flexibility in the cross sections and configuration of streets within
topographically rugged or environmentally sensitive areas.
1.2.3 Pursue other traffic measures to enhance circulation and transient traffic
movements.
Objective 1.3 Maintain the integrity of residential neighborhoods. Discourage through traffic.
Strategies: 1.3.1 Prevent the creation of new roadway connections which adversely impact
existing neighborhoods.
1.3.2 Implement traffic control programs in 1.2.1 to reduce and divert through traffic.
1.3.3 Design new developments and their access points in such a way that the capacity,
of local residential streets is not exceeded.
1.3.4 Minimize impacts of roadways serving the proposed future Diamond Ranch High
School site on surrounding residential neighborhoods.
1.3.5 The City should implement strong measures to maintain the integrity of the
Sunset Crossing Road and other residential areas at the western City limits by
cul-de-sacing Sunset Crossing Road and retaining the cul-de-sacing of
Lycoming, Washington and Beaverhead Streets.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-24
GOAL 2 “Consistent with the Vision Statement, provide a balanced transportation system for
the safe and efficient movement of people, goods and services through the City.”
Objective 2.1 Maximize the use of alternative transportation modes within and through the City
to decrease reliance on single-passenger automobiles.
Strategies: 2.1.1 Maximize the availability and use of public transit service.
2.1.2 Investigate the feasibility of establishing a local transit system. Support privately
funded local transit systems for seniors and youths.
2.1.3 Support mixed-use developments to maximize transportation efficiency.
2.1.4 Pursue a cooperative effort with Caltrans and regional transit providers to
develop a major intermodal transportation facility at the Metrolink Station near
Brea Canyon Road and SR60.
2.1.5 Encourage participation in carpools through the use of City publications and
public displays.
2.1.6 Coordinate to the extent possible with neighboring cities in the development of a
Transportation Demand Management (TDM) plan.
2.1.7 Work with Caltrans to build new Park and Ride sites and expand existing Park
and Ride facilities.
2.1.8 Maintain, expand and upgrade the system of bicycle routes connecting residential
areas to major community attractions utilizing current City design guidelines.
Upgrades of the current system will include investigative means to improve
signing and marking of bikeways. The City shall develop a master plan of
bikeways.
2.1.9 Pursue a cooperative joint agencies program to provide access for Diamond Bar
residents to a regional light rail system.
2.1.10 Lobby Caltrans to provide HOV lanes on local freeways.
2.1.11 Explore the feasibility of interconnected public equestrian trails.
2.1.12 Explore the feasibility of interconnected public hiking trails.
Objective 2.2 Maximize connection of all areas within the City through the circulation system.
Strategies: 2.2.1 Work to ensure that any new development is provided with adequate access from
within the City of Diamond Bar.
2.2.2 Through the roadway system, ensure that new development within the Tres
Hermanos Ranch property is integrated into the community of Diamond Bar.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-25
2.2.3 Work with Pomona Unified School District to provide secondary access to the
future Diamond Ranch High School.
2.2.4 Coordinate with Pomona Unified School District and City of Industry & Urban
Development to insure timely design and construction of secondary access to the
future Diamond Ranch High School.
GOAL 3 “Consistent with the Vision Statement, maintain an adequate level of service on area
roadways.”
Objective 3.1 Improve the safety and efficiency of existing transportation facilities.
Strategies: 3.1.1 Maintain Level of Service “C” or better .at arterial mid-block segments (average
daily) and “D” or better during peak hours at signalized intersections to the
extent possible. (See Level of Service descriptions in Table V-1)
3.1.2 Improve arterial mid-block segments to provide average daily service levels of
“G” or better to prevent use of local and collector streets as alternate routes.
3.1.3 Improve intersections in the City which have peak hour traffic service levels
worse than “D”. Where feasible, these improvements should be made within
existing right-of-way.
3.1.4 Maintain a pavement management system and maintenance program for all
public roadways throughout the City.
3.1.5 Develop a signal system management system and maintenance program for all
traffic signals throughout the City.
3.1.6 Consider all opportunities to expand and maintain pedestrian access routes
throughout the City.
3.1.7 Synchronize signals on all major roads throughout the City of Diamond Bar (see
Circulation Element Figure V-2) and adjacent communities.
Objective 3.2 Explore all available opportunities and mechanisms for funding transportation
improvements.
Diamond Bar General Plan Circulation Element
July 25, 1995 V-26
Strategies: 3.2.1 All new development shall be required to provide mitigation measures. Such
measures could include improvements or traffic impact fees.
3.2.2 Solicit State and Federal funds to improve area freeways to eliminate use of local
streets as part of the freeway system.
3.2.3 Consider implementing a traffic impact fee system.
3.2.4 Develop a regional financing mechanism(s) to assess new development for the
cost of mitigating traffic impacts.
3.2.5 Consider the use of a “toll road” to finance and maintain the environmentally
sensitive transportation corridor.
3.2.6 Continue to solicit State, Federal and other funds to improve local streets.
GOAL 4 “Consistent with the Vision Statement, provide or regulate the provision of the
supply of parking to meeting the needs for both residents and commercial
businesses.”
Objective 4.1 Ensure compliance with the Southern California Air Quality Management
District Regulation 15 trip reduction requirements.
Strategies: 4.1.1 Regulate the provision of preferential parking for high occupancy vehicles
wherever possible.
4.1.2 Consider reductions in parking in exchange for transportation demand
management programs.
Objective 4.2 Provide adequate parking for all types of land use within the City of Diamond
Bar.
Strategies: 4.2.1 Use existing parking demand data sources to update City Code requirements
pertaining to parking, particularly the provision of sufficient parking for land
uses generating a high demand for parking.
4.2.2 Encourage school districts to improve parking and loading facilities for public
schools to minimize the impact on the circulation system.
4.2.3 Establish parking requirements for housing to a level consistent with the
occupants transportation needs.
4.2.4 Strengthen off-street parking codes for new residential development in order to
increase the number of off-street parking spaces.
VI. PUBLIC SERVICES
and FACILITIES ELEMENT
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 i
TABLE OF CONTENTS
PAGE
A. INTRODUCTION.........................................................................................................VI-1
B. EXISTING CONDITIONS............................................................................................VI-2
C. PUBLIC SERVICES AND FACILITIES ISSUES.......................................................VI-3
D. GOALS, OBJECTIVES, AND IMPLEMENTATION STRATEGIES........................VI-4
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 ii
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Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-1
VI. PUBLIC SERVICES AND FACILITIES ELEMENT
A. INTRODUCTION
State law does not require the preparation of a general plan element dealing specifically with public
services and facilities. However, it does state that...
“The general plan may include any other elements or address any other subjects which, in the
judgement of the legislative body, relate to the physical development of the county or city”
(Government Code Section 65303).
Diamond Bar, as a new City, faces many decisions as how to best provide services to the public, and what
types of facilities it needs to build to support those services. Therefore, a local General Plan element
dealing with the long-term provision of municipal services and facilities is appropriate for Diamond Bar.
The actual provision of various public services has already been addressed in the following sections of the
Diamond Bar General Plan:
Section
I. Land Use Element Land Use (for all services & utilities)
III. Resource Management Element Parks and Recreation
Water (and Reclaimed Wastewater)
Energy System
Solid Waste
IV. Public Health and Safety Element Flood Control
Police
Fire
Emergency Services
Disaster Preparedness
The Public Services and Facilities Element seeks to tie the provision of these various services and
facilities together into an integrated strategy for municipal management. The Element focuses on:
• Identifying City facilities and services needed to sustain the community's quality of life
• Long-range planning to fund City services and buildings
• Coordinating and cooperating with various local agencies to provide those services not provided
by the City
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-2
B. EXISTING CONDITIONS
The City presently has a minimum of in-house staff, and contracts out much of the actual service
provision to local public and private agencies. In-house City services include administration, engineering,
planning, parks and recreation, and maintenance of public facilities. The City has established a system for
local collection of solid waste. These daily functions are housed in City Hall, which currently consists of
office space leased in the Gateway Corporate Center.
The major physical assets of the City are its streets and parks, which were originally built by the County.
The existing street system is also in good condition at present. Park maintenance is presently handled by
City staff, although maintenance of the local landscape districts is contracted to private firms.
The County of Los Angeles provides a number of services under contract to the City. Wastewater
conveyance and treatment is provided by County Sanitation District. No. 21. Although much of the
physical sewage infrastructure (pipelines) appear in generally good condition, there have been repeated
failures of the pump stations needed to lift flows to the regional collectors. Currently, there are
approximately 140 lots located within “The Country Estates” that are utilizing on-site waste water
disposal systems.
Flood control is provided by the County Flood Control District. Its facilities are in fairly good condition
with a small amount of seasonal flooding near the intersection of Brea Canyon Road and Diamond Bar
Boulevard.
Solid waste disposal is handled by the County Solid Waste Management Department using several
regional landfills. However, landfill space could run out before the end of the decade.
Law enforcement is handled by the County Sheriff's Department out of the Walnut-San Dimas Station.
Fire protection, emergency evacuation, and response to accidents involving hazardous materials are all
accommodated by the County Fire Department with three stations in and around Diamond Bar.
The Los Angeles County Library System also maintains a very small community library on Grand
Avenue near Diamond Bar Boulevard.
Other services and facilities are provided within Diamond Bar by a variety of public and private agencies.
Domestic water service is provided by the Walnut Valley Water District, which is in turn supplied by
Three Valleys Municipal Water District and ultimately by the Metropolitan Water District of Southern
California. Water facilities are generally adequate.
In terms of energy utilities, electricity is supplied by the Southern California Edison Company, while
natural gas is supplied by the Southern California Gas Company. Energy facilities are generally adequate
to accommodate existing and planned uses.
Comprehensive K-12 educational facilities and programs are provided by the Walnut Valley Unified
School District and the Pomona Unified School District.
Other services within Diamond Bar include branch office postal services administered in Pomona, MTA,
Foothill Transit and OCTA bus systems, Walnut-Diamond Bar YMCA, and Seniors organization.
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-3
C. PUBLIC SERVICES AND FACILITIES ISSUES
If the City decides to provide more local services that are now contracted out, or decides to increase the
levels of existing services, there may be a future need for a larger civic center in a more centralized
location. This long-term facility need would have to be balanced against a community desire for no
increases in local costs. The most cost effective way to provide such a facility would be through a joint
public/private arrangement to build a civic center for the City, most likely in exchange for some kind of
development arrangement. This facility could also house a number of other social programs for City
residents, such as a senior center or a community center.
The City may wish to plan its own long-range program of wastewater conveyance and treatment separate
from Los Angeles County plans. Discussions with Orange County would be needed to determine if a
separate sewage system were feasible. A larger problem would likely be the funding and timing of
construction for some type of new system. Although most of the backbone system is already in place and
designed to flow toward the Los Angeles system, a detailed alternative service plan could be prepared to
address a change in flow direction. The costs and timing of such a new system would have to be weighed
against potential failures of the existing system.
The existing flood control system is presently adequate, but the City should establish if or how any local
costs might accrue as the system ages, so that there are no “surprises” in future budgets. A master
drainage plan will need to be developed for the City and its Sphere of Influence. The City should consider
its responsibility under the National Pollution Discharge Elimination System (NPDES), including to the
maximum extent possible, reasonable measures to minimize the impacts of urban stormwater pollution as
it is collected, conveyed and discharged through the City's flood control system.
The City may decide it wants to take a proactive role in developing long-term solutions to regional solid
waste problems. At a minimum, the City will participate in the mandated planning requirements for
source reduction, recycling, and hazardous waste issues.
Police and fire services are presently adequate. However, the City may wish to study providing its own
protective services, or joining a more local association (non-County) to provide them. In the future, the
Sphere of Influence may require additional police and fire protection as development occurs.
The County's library is not presently adequate for local residents, although there are many other
community libraries in the area that can provide additional resources. The City may want to consider
providing for its own library, or explore joint usage agreements possibly as part of a centralized civic
center complex in the future.
Although local water purveyors can adequately serve the area in terms of facilities, a Statewide drought
could put severe restrictions on the availability of water. The City may wish to take a proactive stance on
securing additional water supplies for itself, or at least keeping current on potential new sources or
limitations.
Energy facilities and systems presently appear adequate, although there may be supply shortages in the
future. The City should take a more active role in energy conservation and the implementation of new
energy technologies. There are numerous governmental and private organizations in the area that might
wish to use City resources to test new programs or devices. The City may wish to take a more proactive
role in planning for its energy future.
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-4
Local schools are presently experiencing overcrowding at some locations at different levels. The State
funding mechanism for constructing new schools will probably not be sufficient to build local schools.
Year-round school or other programs or building modifications may be necessary to continue providing
quality education to local students. The City may choose to work closely with the local districts on site
selection, funding mechanisms and joint use of facilities.
D. GOALS, OBJECTIVES, AND IMPLEMENTATION STRATEGIES
“IT IS THE OVERALL GOAL OF THE PLAN THAT THE CITY ACQUIRE AND MAINTAIN
ADEQUATE RESOURCES TO MEET THE NEEDS OF ITS RESIDENT.”
GOAL 1 “Consistent with the Vision Statement, provide adequate infrastructure facilities and
public services to support development and planned growth.”
Objective 1.1 Maintain adequate systems for water supply and distribution;
Wastewater/sewage collection, treatment, and disposal; solid waste collection
and disposal; and energy distribution which are capable of meeting the needs of
the residents of Diamond Bar
Strategies: 1.1.1 Prior to permitting a major extension of services or utilities to facilitate changes
in land use, conduct a thorough review of all social, economic, and
environmental factors associated with that extension; require the implementation
of appropriate mitigation measures.
1.1.2 Protect existing residents and businesses from the cost of financing
infrastructure aimed at supporting new development or the intensification of
development.
1.1.3 Require the construction of water, sewer, drainage and other necessary public
facilities prior to or concurrent with each new development.
1.1.4 Require the project sponsor to provide all necessary infrastructure
improvements (including the pro rata share of system-wide improvements).
1.1.5 Coordinate the long-term provision of utility services, including water,
wastewater, sewage, electricity, natural gas, solid waste, etc. to assure adequate
future levels of services for City residents.
(a) Monitor plans by the Metropolitan Water District and City of Industry to
locate a water reservoir in upper Tonner Canyon.
(b) Support development of appropriately sited, environmentally sensitive,
solid waste treatment facilities which do not impact resident's quality of
life.
1.1.6 Require all new housing subdivisions be connected to a public sewage system.
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-5
Objective 1.2 Establish and implement solutions to the financing of public facilities and
services which best protect the interests of the taxpayer.
Strategies: 1.2.1 Establish a development fee structure which best assures that costs for new
capital facilities and expansion of existing facilities necessitated by the approval
of new development or intensification of existing development are funded by the
proponents or beneficiaries of projects, in proportion to the demand created by
the development.
1.2.2 Investigate and, if feasible, initiate the establishment of a redevelopment agency
in the City of Diamond Bar to facilitate the mitigation of traffic and circulation
deficiencies, the financing of public improvements and other similar tasks.
Objective 1.3 Provide residents with access to high quality local educational facilities.
Strategies: 1.3:1 Continue a cooperative program. with the Pomona Unified School District to
construct a high school in the City of Diamond Bar on Tres Hermanos Ranch. As
part of high school development, pursue development of a major joint use
recreational facility (e.g. auditorium pool, ball fields, tennis, football/soccer
courts, stadium, gymnasium).
1.3.2 Work closely with the Walnut Valley and Pomona Unified School Districts on
an ongoing basis to resolve issues such as joint use of facilities, location of new
facilities, and alternative use of vacant or unused sites.
13.3 Encourage joint development of recreational facilities with the local school
districts.
1.3.4 Enable, through appropriate zoning and development regulations or with a
Conditional Use Permit, the construction and operation of private school
facilities.
Objective 1.4 Enable, through appropriate zoning' and development regulations, the provision
of cultural facilities, such as educational institutions, museums, and performing
arts facilities, to meet the needs of Diamond Bar residents.
Strategies: 1.4.1 Pursue the acquisition of a site and development of a civic center, including a
multi-use community center.
1.4.2 Monitor plans of the University of California to locate new campuses in
Diamond Bar.
1.4.3 Work with Los Angeles County to insure adequate library services are provided.
Objective 1.5 Stimulate opportunities for a population which is diverse in terms of age,
occupation, income, race, interests, and religion to interact, exchange ideas, and
establish and realize common goals.
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-6
Strategies: 1.5.1 Retain and provide community social gathering places, including active and
natural park lands and one or more community centers. In private commercial
and office complexes encourage. the development of plaza areas.
1.5.2 Maintain a public information program to. inform residents of community events.
(a) Whenever possible, establish permanent locations and regular dates for
community events to improve attendance.
(b) Encourage a “Community Calendar” as part of the local cable television
programming to inform residents about the times and locations of upcoming
community events.
1.5.3 Within new residential developments, encourage organization of individual
neighborhoods and discourage through traffic on local streets while maintaining
pedestrian and bicycle continuity and encourage neighborhood parks,
improvement programs and social events.
GOAL 2 “Consistent with the Vision Statement, achieve a fiscally solvent, financially table
community.”
Objective 2.1 Provide sufficient, opportunities for retail and other, non-residential commercial
and office uses as necessary to maximize municipal income to finance desired
community amenities.
Strategies: 2.1.1 Promote the intensification of the sales tax generating potential of existing and
future commercial areas within the City.
2.1.2 Work with State officials and local elected representatives to make a determined
effort to promote statewide legislation that would secure guaranteed long-term
stable financing of local government based primarily upon property tax revenues.
Alternatively, support legislation that would redistribute sales tax revenues to
local agencies based upon an equitable formula that would include both the
location where the sales tax revenue was collected and the population of each
local agency involved.
2.1.3 Pursue the expansion of municipal boundaries to areas which can be utilized to
assist in the provision of sufficient municipal income to provide the high level of
services and facilities demanded by Diamond Bar residents.
2.1.4 Utilize public cost/benefit and/or fiscal impact analysis in the review of new
development proposals and in determining acceptability.
Objective 2.2 Promote efficiency in the provision of public services and facilities.
Strategies: 2.2.1 Conduct periodic review of user charges, development fees, and public facilities
impact mitigation fees in accordance with California Government Code Section
66000 et al, (AB1600) to ensure that the charges are consistent with the costs of
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-7
improvement and maintenance, and that public services and facilities are being
expanded in a cost-efficient manner.
Objective 2.3 Promote public and private services and amenities to the community.
Strategies: 2.3.1 Identify and pursue opportunities for private provision of services and facilities
within the City of Diamond Bar, including joint public/private efforts.
2.3.2 Explore joint or cooperative use of facilities owned or constructed by other
public agencies. Potential locations include, but are not limited to, the Pomona
Unified School District High School site in the Tres Hermanos area; Site “D”
owned by the Walnut Valley Unified School District off of Diamond Bar
Boulevard east of the SR57; South Pointe Middle School; and the Walnut Valley
Unified School District school/office site on Lemon Avenue just north of the
SR60.
2.3.3 Provide regular information to citizens regarding current issues, public safety
information, resource management information, city services, public meeting
schedules, hazardous material collection programs, etc.
Diamond Bar General Plan Public Services and Facilities Element
July 25, 1995 VI-8
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