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HomeMy WebLinkAboutRE_ EXTERNAL_ Fwd_ Canyon Loop Trail Project_ Intervention RequestThank you Dick From: Richard Fisher <rfisher@rfaland.com> Sent: Monday, November 7, 2022 12:31 PM To: Ryan Wright <RWright@DiamondBarCA.Gov>; Malik, Anisha <Anisha.Malik@mbakerintl.com>; Winkleman, Ryan <Ryan.Winkleman@mbakerintl.com> Cc: Ashimine, Alan <aashimine@mbakerintl.com>; Phaneuf, Ryan <Ryan.Phaneuf@mbakerintl.com> Subject: RE: EXTERNAL: Fwd: Canyon Loop Trail Project, Intervention Request CAUTION: This message originated outside of our City of Diamond Bar network. **Please exercise caution when opening attachments or clicking links, especially from unknown senders.** Ryan: A couple of thoughts: * With the construction of (14) trail water diverters, which are added to the regraded trail, we anticipate a reduction of soil erosion which can expect to increase if concentrated flows are allowed to run down the trail surface for extended distances. * All water flows from the trail are frequently directed to the nearby natural drainage topography, so this water will remain on the overall project site. * The cobble swales are critical to capture rainfall which runs down to the new timber stairs being constructed, and * Will stop erosion under the timber stair assemblies. * Have “natural-appearing” rock cobble to lend a more natural look to this drainage improvement. Although smaller in size, the inlaid cobble is the same color/texture as the rock fill for the Gabion Wall components. * Flows during rain events will be directed off of the trail surface as quickly as the surrounding terrain allows. Due to the above design features, we are confident that the soil stabilization program associated with this trail improvement project will be significantly improved. Steep segments of the trail, both potentially creating a slip-and-fall condition, and suffering from accelerated erosion. These are cordoned off from further use, and will be receiving native seed mixes to gradually return these areas to the natural vegetation. Thanks. Dick Fisher Richard Fisher Associates 4902 Kron Street, Irvine CA 92604 (714) 342-5467 rfisher@rfaland.com <mailto:rfisher@rfaland.com> From: Ryan Wright <RWright@DiamondBarCA.Gov <mailto:RWright@DiamondBarCA.Gov> > Sent: Monday, November 7, 2022 11:58 AM To: Malik, Anisha <Anisha.Malik@mbakerintl.com <mailto:Anisha.Malik@mbakerintl.com> >; Winkleman, Ryan <Ryan.Winkleman@mbakerintl.com <mailto:Ryan.Winkleman@mbakerintl.com> > Cc: Richard Fisher <rfisher@rfaland.com <mailto:rfisher@rfaland.com> >; Ashimine, Alan <aashimine@mbakerintl.com <mailto:aashimine@mbakerintl.com> >; Phaneuf, Ryan <Ryan.Phaneuf@mbakerintl.com <mailto:Ryan.Phaneuf@mbakerintl.com> > Subject: RE: EXTERNAL: Fwd: Canyon Loop Trail Project, Intervention Request Thank you Anisha! Dick, did you have any brief comments I may include regarding the cobble stone swales? Thank You, Ryan From: Malik, Anisha <Anisha.Malik@mbakerintl.com <mailto:Anisha.Malik@mbakerintl.com> > Sent: Friday, November 4, 2022 3:39 PM To: Ryan Wright <RWright@DiamondBarCA.Gov <mailto:RWright@DiamondBarCA.Gov> >; Winkleman, Ryan <Ryan.Winkleman@mbakerintl.com <mailto:Ryan.Winkleman@mbakerintl.com> > Cc: Richard Fisher (rfisher@rfaland.com <mailto:rfisher@rfaland.com> ) <rfisher@rfaland.com <mailto:rfisher@rfaland.com> >; Ashimine, Alan <aashimine@mbakerintl.com <mailto:aashimine@mbakerintl.com> >; Phaneuf, Ryan <Ryan.Phaneuf@mbakerintl.com <mailto:Ryan.Phaneuf@mbakerintl.com> > Subject: RE: EXTERNAL: Fwd: Canyon Loop Trail Project, Intervention Request CAUTION: This message originated outside of our City of Diamond Bar network. **Please exercise caution when opening attachments or clicking links, especially from unknown senders.** Please refer to my notes below in blue. For the bioswale comment, I would see if Dick has anything to add in on the design side. My comments for that one are more general overall as I’m not as well versed in all the locations of each feature on site and the reasonings behind why they were placed there. We do utilize cobble and gabion structures within restoration sites though and the reg agencies have been fine with it, so I don’t think there is really an issue here with it as well. I’m not sure of the timeline you need to respond to her letter, but if there is a meeting with CDFW on site next week I would recommend holding until then. That way you can add in their concurrence as well. Since I’ll be out starting next week, Ryan P. can assist with any additional questions you might have. Thanks, Anisha -----Original Message----- From: Ryan Wright <RWright@DiamondBarCA.Gov <mailto:RWright@DiamondBarCA.Gov> > Sent: Thursday, November 3, 2022 4:46 PM To: Malik, Anisha <Anisha.Malik@mbakerintl.com <mailto:Anisha.Malik@mbakerintl.com> >; Winkleman, Ryan <Ryan.Winkleman@mbakerintl.com <mailto:Ryan.Winkleman@mbakerintl.com> > Cc: Richard Fisher (rfisher@rfaland.com <mailto:rfisher@rfaland.com> ) <rfisher@rfaland.com <mailto:rfisher@rfaland.com> >; Ashimine, Alan <aashimine@mbakerintl.com <mailto:aashimine@mbakerintl.com> >; Phaneuf, Ryan <Ryan.Phaneuf@mbakerintl.com <mailto:Ryan.Phaneuf@mbakerintl.com> > Subject: RE: EXTERNAL: Fwd: Canyon Loop Trail Project, Intervention Request Thanks Anisha. You are correct on all points. I think her personal preference is for bioswales rather than cobble stones swales. -----Original Message----- From: Malik, Anisha <Anisha.Malik@mbakerintl.com <mailto:Anisha.Malik@mbakerintl.com> > Sent: Thursday, November 3, 2022 4:42 PM To: Winkleman, Ryan <Ryan.Winkleman@mbakerintl.com <mailto:Ryan.Winkleman@mbakerintl.com> >; Ryan Wright <RWright@DiamondBarCA.Gov <mailto:RWright@DiamondBarCA.Gov> > Cc: Richard Fisher (rfisher@rfaland.com <mailto:rfisher@rfaland.com> ) <rfisher@rfaland.com <mailto:rfisher@rfaland.com> >; Ashimine, Alan <aashimine@mbakerintl.com <mailto:aashimine@mbakerintl.com> >; Phaneuf, Ryan <Ryan.Phaneuf@mbakerintl.com <mailto:Ryan.Phaneuf@mbakerintl.com> > Subject: RE: EXTERNAL: Fwd: Canyon Loop Trail Project, Intervention Request CAUTION: This message originated outside of our City of Diamond Bar network. **Please exercise caution when opening attachments or clicking links, especially from unknown senders.** Hi Ryan, I will work on response points for you on the items below and provide them to you tomorrow. It sounds like she's misunderstanding some items associated with the project. To confirm, there's no permanent irrigation being installed, correct? My understanding is the pipes in place are solely for construction purposes and would be removed once complete. It's common practice to have temporary irrigation lines as well within restoration projects, so the agencies wouldn't take issue to that either. Also, as I'm sure you've discussed with Ryan Winkleman, we aren't impacting anything that would trigger a CDFW permit so we are set there. During your call, did she mention where exactly she would want to see the bioswales? I'm curious if those comments are specific to the trail or more so in general for the area. I would argue you are pushing for a watershed approach, especially with doing additional enhancement and restoration activities within the area instead of going off site to a mitigation bank. Thanks, Anisha -----Original Message----- From: Winkleman, Ryan <Ryan.Winkleman@mbakerintl.com <mailto:Ryan.Winkleman@mbakerintl.com> > Sent: Thursday, November 3, 2022 3:55 PM To: Ryan Wright <RWright@DiamondBarCA.Gov <mailto:RWright@DiamondBarCA.Gov> >; Malik, Anisha <Anisha.Malik@mbakerintl.com <mailto:Anisha.Malik@mbakerintl.com> > Cc: Richard Fisher (rfisher@rfaland.com <mailto:rfisher@rfaland.com> ) <rfisher@rfaland.com <mailto:rfisher@rfaland.com> >; Ashimine, Alan <aashimine@mbakerintl.com <mailto:aashimine@mbakerintl.com> >; Phaneuf, Ryan <Ryan.Phaneuf@mbakerintl.com <mailto:Ryan.Phaneuf@mbakerintl.com> > Subject: RE: EXTERNAL: Fwd: Canyon Loop Trail Project, Intervention Request Ryan, I'm copying Anisha on this as I think this is more in her realm of expertise. Ryan Winkleman | Project Manager/Senior Biologist/Certified Senior Ecologist 5 Hutton Centre Drive, Suite 500 | Santa Ana, CA 92707 | [O] 949-330-4115 | [M] (949) 533-0918 ryan.winkleman@mbakerintl.com <mailto:ryan.winkleman@mbakerintl.com> | www.mbakerintl.com <https://linkprotect.cudasvc.com/url?a=http%3a%2f%2fwww.mbakerintl.com&c=E,1,dQmqLunp5RzlTkmlUIczvSZPVrAPG0iTrYmwfC3qzHsJAKlIge0z9KtIyFI2BeWBIT_G7fqKVoVs05XqC3hokNkIvdNLFrvkXxf2uuY99rLrUzjZltpVggQ,& typo=1> -----Original Message----- From: Ryan Wright <RWright@DiamondBarCA.Gov <mailto:RWright@DiamondBarCA.Gov> > Sent: Thursday, November 3, 2022 3:46 PM To: Richard Fisher (rfisher@rfaland.com <mailto:rfisher@rfaland.com> ) <rfisher@rfaland.com <mailto:rfisher@rfaland.com> >; Winkleman, Ryan <Ryan.Winkleman@mbakerintl.com <mailto:Ryan.Winkleman@mbake rintl.com> > Subject: EXTERNAL: Fwd: Canyon Loop Trail Project, Intervention Request Good Afternoon, Please provide your thoughts regarding the email below. If you would like to call tomorrow that will work as well. Thanks Ryan ________________________________ From: Cynthia Robin Smith <diamondbarbeautiful@gmail.com <mailto:diamondbarbeautiful@gmail.com> > Sent: Thursday, November 3, 2022, 3:13 PM To: Rwright@diamondbarca.gov <mailto:Rwright@diamondbarca.gov> <Rwright@diamondbarca.gov <mailto:Rwright@diamondbarca.gov> > Subject: Canyon Loop Trail Project, Intervention Request CAUTION: This message originated outside of our City of Diamond Bar network. **Please exercise caution when opening attachments or clicking links, especially from unknown senders.** TO: Mr. Ryan Wright, Project Mgr. City of Diamond Bar Los Angeles County RE: City of Diamond Bar, Canyon Loop Trail Project - Oversight Dear Ryan, I am grateful for the conversation we had on the phone this week. I hope this letter will clarify my concerns about this active project and that changes can be made before serious damage is done. I understand the Canyon Loop Trail construction project intends to install PVC drainage piping and a mechanical irrigation system in this sensitive natural habitat area. Also, I previously informed you that the City's routine installation of cement and cobblestone gutters, tracing the trails, is inferior and causes erosion and soil degradation. This mechanically-engineered system wastes water and will cause years of incremental degradation. * The placement of PVC piping is only intended for the duration of construction and will be thoroughly removed following its completion. To avoid any detriment to the surrounding sensitive habitats, we have daily biological monitors on site to oversee the construction team with both their activities and any staging that is occurring. Daily review also identifies any listed species observed nearby so areas can be avoided. * I don’t know the full extent of BMPs being used at all during construction, but depending on what’s in place that might be good to mention here as well. * As a side note, it’s hard to quantify potential degradation without having a hydrological study being completed. I’m unaware of the level of flows the site receives during the wet season, but I don’t see this project causing significant erosion to occur within the area. Problems These methods also violate CEQA and are an inferior mitigation for erosion and water management on watershed habitats. * I haven’t looked into the full extent of the on site flows, but where are the drop off points are for gutters? I don’t think this would violate CEQA as we are not redirecting flow paths or causing any impediments to the current drainage on site. The placement of the gutters are mainly to avoid flooding on the trails, correct? As long as we are not causing any increased flow velocity with these structures (it sounds like we will more be doing the opposite) then I don’t see it as an issue for erosion. The slopes are all well vegetated surrounding the trails as well, if they were more barren then I would be more concerned of erosion occurring. * Also, the project would not cause any loss of water on site and would still allow for groundwater recharge and percolation. Tradecraft Differences The City's present choice of design is based on architectural engineering that is contrary to ecological land management practices and which do not support native vegetation, stormwater management or watershed conditions. PVC piping, manufactured hydration systems (sprinklers) and cement gutters will alter the (watershed) hydrology of the site, damaging the natural setting and increasing maintenance service costs in future. Wasting water and budget resources. * The project is intended to improve the current trail system while maintaining the multiple habitats found within our open space area. Construction practices have been discussed with the US Department of Fish and Wildlife to promote the least amount of impacts to our existing vegetation. Additionally, we are restoring and enhancing additional areas nearby the trail to meet requests of California Department of Fish and Wildlife and promote benefits to our local wildlife and watershed overall. In discussions with the agency, we chose to focus mitigation funding on improving the habitats within our open space for our local coastal California gnatcatchers to utilize rather than funding mitigation banks at off-site locations. (I highlighted this since it is an approach with an ecology first mindset, but I don’t want this to potentially open up more discussions with her, so you might want to leave it out.) * Again, I’m not seeing where the sprinklers and cement gutters are on the design plans. Does she mean the trail water diverters? The existing native vegetation on site is not receiving any supplemental irrigation, and the native habitats are well established that they will continue to receive natural rainfall and maintain themselves on their own. You could argue that any minor diversions from portions of the trail that flood actually are helping avoid potential erosion occurring along the slopes naturally as well. Guidance & Permits Required I have spoken with the California Department of Fish and Wildlife. They informed me the City has not contacted them for the proper guidance and permits associated with my complaints here. (USGS maps indicate jurisdictional hydrological features in the project area.) * During the design phase of the project, jurisdictional features were reviewed to avoid any potential direct or indirect impacts to waters. One jurisdictional drainage feature is situated near the center of the Canyon Loop Trail survey area, in the canyon between the two trails that are being improved. The feature is ephemeral, likely carrying flows only during rain events. It crosses the trail system twice but only as sheet flow, with no culvert passage evident under the trails. This drainage does not qualify as waters of the U.S. under the U.S. Army Corps of Engineers, but you are correct in that it would still qualify as waters of the State under the regulatory authority of the Regional Water Quality Control Board and as a jurisdictional streambed under the California Department of Fish and Wildlife. However, since no work will occur within the drainage feature, regulatory permits from these agencies (such as the Section 1600 Lake and Streambed Alteration Agreement) are not required. * I included the Regional Board comment as well since it looks like she copied them on the email. A 401 certification wouldn’t be required for this. I believe CEQA outlined a Construction General Permit and prepared SWPPP, so that would be the only thing the Regional Board would be tied in on. * We are currently working with the California Department of Fish and Wildlife on our proposed enhancement and restoration of sensitive habitats in adjoining locations of the trail. Additionally, we’ve coordinated with the US Fish and Wildlife Service to protect our sensitive species, such as the coastal California gnatcatcher. The project is compliant with all CEQA requirements as well. Solutions There are better solutions for conserving water on site that coincide with best natural land management practices. Bio-swales and pocket "dams", which are permeable plant, compost, rock and gravel formations are excellent mitigation improvements. Bio-swales capture rainfall, arrest the process of erosion by slowing water down when it flows across a slope. Any soil that has been carried off from uphill is deposited in the bottom of the bio-swale reducing erosion, recharging groundwater and building soil. Bio-swales are a superior watershed management strategy. * Dick Fisher might be the best at providing more info on this one, since I think you could highlight some of the design choices that were made with the water components (swales, gabion structures). * I will say that while bioswales are an effective means of green infrastructure, but the cobblestone swales will offer similar benefits to slow water runoff and allow natural percolation into the soil on site. Flows as we discussed earlier are also tied more to rainfall. So with that, the water source for plantings for a bioswale would be more tied to that. My understanding is we want more grasses to be used within features like that, and I’m not sure how well those would even establish based on their location and the site hydrology. * Also, she references the bioswales more to capture the hydrology from “uphill”, the only place that would make sense is on the west end of the trail. We wouldn’t want to make any changes there due to the jurisdictional feature and other sensitive habitats within the surrounding area. The goal is to avoid any shifts in the existing hydrology of the site. She might just be looking for additional improvements to tack on with the current project, but in this case I don’t think it makes sense to include. * The improvements being made to the trail would reduce stormwater runoff and improve water quality , and the proposed structures would reduce soil erosion and loss of topsoil compared to existing conditions. A Request On behalf of Diamond Bar residents, I again request the City of Diamond Bar perform a change-order to instead use a "watershed" supportive approach to drainage and irrigation on the trail. Please communicate to me your impression of this request and keep me informed of the progress of the Canyon Loop Trail project. Thank you. C. Robin Smith Cynthia Robin Smith, Naturalist, Conservation Gardener, Teacher California Native Trees, Landscapes; Wildlife Habitat & Biodiversity Conservation Diamond Bar Preservation Foundation, Conservation Consultant Conejo Ridge Native Garden, Outdoor Classroom, Director Diamond Bar - Pomona Valley Sierra Club, Angeles Chapter 324 S. Diamond Bar Blvd., #230 Diamond Bar CA 91765 951-675-6760 Mobile CC: CDFW, Victoria Tang Walnut Valley Water District, Director Hilden Los Angeles Water Quality Control Board, Stormwater Management CEQA and are an inferior mitigation for erosion and water management on watershed habitats. * I haven’t looked into the full extent of the on site flows, but where are the drop off points are for gutters? I don’t think this would violate CEQA as we are not redirecting flow paths or causing any impediments to the current drainage on site. The placement of the gutters are mainly to avoid flooding on the trails, correct? As long as we are not causing any increased flow velocity with these structures (it sounds like we will more be doing the opposite) then I don’t see it as an issue for erosion. The slopes are all well vegetated surrounding the trails as well, if they were more barren then I would be more concerned of erosion occurring. * Also, the project would not cause any loss of water on site and would still allow for groundwater recharge and percolation. Tradecraft Differences The City's present choice of design is based on architectural engineering that is contrary to ecological land management practices and which do not support native vegetation, stormwater management or watershed conditions. PVC piping, manufactured hydration systems (sprinklers) and cement gutters will alter the (watershed) hydrology of the site, damaging the natural setting and increasing maintenance service costs in future. Wasting water and budget resources. * The project is intended to improve the current trail system while maintaining the multiple habitats found within our open space area. Construction practices have been discussed with the US Department of Fish and Wildlife to promote the least amount of impacts to our existing vegetation. Additionally, we are restoring and enhancing additional areas nearby the trail to meet requests of California Department of Fish and Wildlife and promote benefits to our local wildlife and watershed overall. In discussions with the agency, we chose to focus mitigation funding on improving the habitats within our open space for our local coastal California gnatcatchers to utilize rather than funding mitigation banks at off-site locations. (I highlighted this since it is an approach with an ecology first mindset, but I don’t want this to potentially open up more discussions with her, so you might want to leave it out.) * Again, I’m not seeing where the sprinklers and cement gutters are on the design plans. Does she mean the trail water diverters? The existing native vegetation on site is not receiving any supplemental irrigation, and the native habitats are well established that they will continue to receive natural rainfall and maintain themselves on their own. You could argue that any minor diversions from portions of the trail that flood actually are helping avoid potential erosion occurring along the slopes naturally as well. Guidance & Permits Required I have spoken with the California Department of Fish and Wildlife. They informed me the City has not contacted them for the proper guidance and permits associated with my complaints here. (USGS maps indicate jurisdictional hydrological features in the project area.) * During the design phase of the project, jurisdictional features were reviewed to avoid any potential direct or indirect impacts to waters. One jurisdictional drainage feature is situated near the center of the Canyon Loop Trail survey area, in the canyon between the two trails that are being improved. The feature is ephemeral, likely carrying flows only during rain events. It crosses the trail system twice but only as sheet flow, with no culvert passage evident under the trails. This drainage does not qualify as waters of the U.S. under the U.S. Army Corps of Engineers, but you are correct in that it would still qualify as waters of the State under the regulatory authority of the Regional Water Quality Control Board and as a jurisdictional streambed under the California Department of Fish and Wildlife. However, since no work will occur within the drainage feature, regulatory permits from these agencies (such as the Section 1600 Lake and Streambed Alteration Agreement) are not required. * I included the Regional Board comment as well since it looks like she copied them on the email. A 401 certification wouldn’t be required for this. I believe CEQA outlined a Construction General Permit and prepared SWPPP, so that would be the only thing the Regional Board would be tied in on. * We are currently working with the California Department of Fish and Wildlife on our proposed enhancement and restoration of sensitive habitats in adjoining locations of the trail. Additionally, we’ve coordinated with the US Fish and Wildlife Service to protect our sensitive species, such as the coastal California gnatcatcher. The project is compliant with all CEQA requirements as well. Solutions There are better solutions for conserving water on site that coincide with best natural land management practices. Bio-swales and pocket "dams", which are permeable plant, compost, rock and gravel formations are excellent mitigation improvements. Bio-swales capture rainfall, arrest the process of erosion by slowing water down when it flows across a slope. Any soil that has been carried off from uphill is deposited in the bottom of the bio-swale reducing erosion, recharging groundwater and building soil. Bio-swales are a superior watershed management strategy. * Dick Fisher might be the best at providing more info on this one, since I think you could highlight some of the design choices that were made with the water components (swales, gabion structures). * I will say that while bioswales are an effective means of green infrastructure, but the cobblestone swales will offer similar benefits to slow water runoff and allow natural percolation into the soil on site. Flows as we discussed earlier are also tied more to rainfall. So with that, the water source for plantings for a bioswale would be more tied to that. My understanding is we want more grasses to be used within features like that, and I’m not sure how well those would even establish based on their location and the site hydrology. * Also, she references the bioswales more to capture the hydrology from “uphill”, the only place that would make sense is on the west end of the trail. We wouldn’t want to make any changes there due to the jurisdictional feature and other sensitive habitats within the surrounding area. The goal is to avoid any shifts in the existing hydrology of the site. She might just be looking for additional improvements to tack on with the current project, but in this case I don’t think it makes sense to include. * The improvements being made to the trail would reduce stormwater runoff and improve water quality , and the proposed structures would reduce soil erosion and loss of topsoil compared to existing conditions. A Request On behalf of Diamond Bar residents, I again request the City of Diamond Bar perform a change-order to instead use a "watershed" supportive approach to drainage and irrigation on the trail. Please communicate to me your impression of this request and keep me informed of the progress of the Canyon Loop Trail project. Thank you. C. Robin Smith Cynthia Robin Smith, Naturalist, Conservation Gardener, Teacher California Native Trees, Landscapes; Wildlife Habitat & Biodiversity Conservation Diamond Bar Preservation Foundation, Conservation Consultant Conejo Ridge Native Garden, Outdoor Classroom, Director Diamond Bar - Pomona Valley Sierra Club, Angeles Chapter 324 S. Diamond Bar Blvd., #230 Diamond Bar CA 91765 951-675-6760 Mobile CC: CDFW, Victoria Tang Walnut Valley Water District, Director Hilden Los Angeles Water Quality Control Board, Stormwater Management