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HomeMy WebLinkAboutC_MuckleshootResponse_200724_V1.pdf 750 Sixth Street South | Kirkland, WA 98033 P 425.822.5242 | f 425.827.8136 | watershedco.com July 24, 2020 Matt Herrera City of Renton Community & Economic Development 1055 S. Grady Way Renton, WA 98057 Re: Cedar River Apartments – Muckleshoot Response The Watershed Company Reference Number: 170314 Dear Matt: The purpose of this letter is to provide responses to comments received from the Muckleshoot Tribe in an email dated August 29, 2019. The comments are regarding the Cedar River Apartments project at 1915 Maple Valley Highway (LUA19-000161). The comments are summarized below, as received via email, followed by The Watershed Company’s (Watershed’s) response. This project represents an opportunity to restore river processes in the Cedar River at this location that has been significantly altered over time as documented in the Golder October 30, 2018 Shoreline Stabilization memo for this project. Per the memo, the most “recent” activity at the site affecting river processes is the concrete block retaining wall noted in existence as of the 2002 aerial photograph in the memo. This raises questions: 1. Was this retaining wall fully permitted by Renton, WDFW and any federal agencies that required permits? If no, then the wall should not be viewed as a legal structure for purposes of this redevelopment project. It is proposed for retention without modification currently. Response: The wall is part of shoreline stabilization measures that were legally established on this site prior to enactment of the Shoreline Management Act. Please see Watershed’s memorandum dated July 24, 2020, responding to Comment # 5 of the City of Renton’s December 4, 2019 “On Hold” Notice, and supplementing the historic analysis provided in the Golder memorandum dated October 30, 2018. Response to Muckleshoot Comments Cedar River Apartments July 24, 2020 Page 2 2. If yes, was the wall built meeting current engineering standards at the time? Has it ever needed maintenance? Response: The wall is part of shoreline stabilization measures legally established on this site since at least the 1960s. In 1976, the City of Renton issued an exemption from shoreline substantial development permitting to repair portions of the foundation of the wall. Additionally, the Washington State Department of Fisheries and Game issued a Hydraulic Project Approval related to this repair. Watershed’s memorandum dated July 24, 2020 includes copies of these permits. It may be desirable to keep the wall as is; however, if it does not meet current engineering and flood control needs, it should be reconsidered. Further, it appears that the wall was intended to be removed as part of the Site 7 restoration project (Right Bank, River Mile 1.8 to 2.15) from the Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Feasibility Analysis Report (Herrera 2015) which states: “Enhance right bank in conjunction with Tri-Park Master Plan redevelopment to flatten right bank to provide shallow edge habitat at range of flows, remove invasive vegetation and armoring, and/or install LWD and bioengineered native plantings.” Response: The existing wall has been assessed by a structural engineer (Re: Bulkhead Wall Stability Addendum, DCI Engineers, June 12, 2019) (“DCI Addendum”) and by a geotechnical consultant (Bulkhead Wall Stability Addendum, Terracon Consultants, June 10, 2019) (“Terracon Addendum”) (Bulkhead Wall Stability Addendum No. 2, Terracon Consultants, May 21, 2020) (Terracon Addendum 2.0) (Bulkhead Wall Stability – Response Letter Addendum No. 3, Terracon Consultants, July 24, 2020) (Terracon Addendum 3.0). A scour analysis (Cedar River Apartments Scour Analysis Technical Report, The Watershed Company, March 31, 2020; revised July 10, 2020) and channel migration risk assessment (Channel Migration Risk Assessment Memo, The Watershed Company, April 8, 2020) have also been performed. Collectively, these studies have found that the wall is stable, with no evidence of deterioration or movement. Further, no evidence was found to suggest an impending failure under normal loading conditions. It was also determined that the proposed development would not increase loading on the wall. As such, the wall, in its existing condition, is stable, and requires no improvements or repairs. Regarding removal of the wall, the project team is aware of the mentioned report (Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat Restoration Site Potential and Response to Muckleshoot Comments Cedar River Apartments July 24, 2020 Page 3 Feasibility Analysis Report, Herrera Environmental Consultants, November 5, 2015) (Herrera Report). The report was prepared for the City of Renton under a grant from Puget Sound Partnership’s Puget Sound Acquisition and Restoration Fund program to study potential Chinook salmon habitat restoration sites in the lower Cedar River. The study included detailed analysis and conceptual design for fourteen sites deemed to have good opportunity for restoration. One of these sites (Site 7) is the subject site. The subject site was included as a suitable candidate for restoration because public acquisition of the parcel was anticipated as envisioned in the 2006 Tri-Park Master Plan. However, public acquisition of the site did not occur and it remains under private ownership. Nevertheless, removal of the wall was considered as part of the current development proposal. However, it is not financially feasible for the property owner to implement the full restoration design conceptualized in the Herrera Report. Estimated costs described in the Herrera Report to implement the restoration plan (approximately $2.7 million in 2015) significantly underrepresent the total cost that would be necessary to permit, excavate, and remove the existing shoreline stabilization measures on this site. First, only through extensive assessment work done as part of the current project proposal has the scale and extent of on-site buried concrete come to light. See generally Terracon Addendum. Specifically, soils explorations have determined that the existing concrete block wall sits atop a mass of poured concrete. The mass spans the entire length of the wall and extends to at least a depth common with the bottom of the river. Additional layers of concrete are present throughout other areas of the site. Full restoration, as envisioned by the Herrera Report, would require removal of the entirety of the concrete wall, along with the concrete mass along the river’s edge. The large expense associated with excavation and removal of the concrete mass was not considered. Secondly, it is unlikely that estimated excavation quantities accounted for groundwater contamination on-site. That is, due to on- site contamination from past site uses, removing the wall and subjecting the river to newly exposed soils would be problematic. Such an action, coupled with any future movement of the river, could result in contaminated groundwater reaching the river. Thus, full stream restoration would need to account for contaminated groundwater by over-excavating on- site soils, with the need to then import clean materials to be placed within the new buffer. Finally, the estimate for a more limited scope of work was prepared in 2015; construction costs have increased significantly in the last five years. Thus, the estimate provided in the Herrera Report understates true restoration costs significantly. Response to Muckleshoot Comments Cedar River Apartments July 24, 2020 Page 4 Although the existing wall will not be removed entirely, the current proposal does include significant restoration including partial wall removal, adherence to the full shoreline buffer width and restoration planting of the buffer which will greatly increase ecological function over existing conditions. In sum, although the subject site was identified as a potential restoration site for purposes of public acquisition as a park, such acquisition did not occur. Regardless, multiple factors make full restoration infeasible as part of a privately owned redevelopment proposal, including extensive rehabilitation necessary to excavate deep layers of concrete, resulting contamination of on-site groundwater and clean-up, and costs associated with restoration. Therefore, the selected proposal, which includes partial wall removal and full restoration of the buffer is the preferred alternative. Project Environmental review approach and considerations We agree with the City’s initial assessment that this project should undergo an environmental impact statement process. An EIS process will enable a variety of alternatives for the site, including modifications to the existing shoreline stabilization wall, the proposed riparian plantings, and the extent, number and location of trails in the regulated shoreline as shown in the site plan to be considered and their environmental impacts fully considered. This is particularly true because as discussed in project application materials, the site is in a channel migration area of the Cedar River. This project represents an opportunity to restore some/all of the salmon habitat functions that occur in channel migration areas. As described currently, there is only one alternative, the proposed action/site plan. An EIS would enable a fully consideration of the river bank options identified in the Golder October 30, 2018 memo. Now that the cement plant is gone, the time to correct the site’s impacts to the Cedar River is now. The existing river impairments (fill, retaining wall, concrete wash ponds) confine the likely contributed to redd scour and reduce habitat quality/quantity by coarsening the streambed substrate, and limits salmon production. The applicant also proposes to place fill within the 100- year flood plain, where mitigation is provided via onsite compensatory flood storage without significant modification to the shoreline and riverine functions. It is also not clear how the proposed fill and CLOMR application will reduce opportunities to restore the natural channel migration that would occur if not for the existing built structures. The project proposal appears to be inconsistent and will likely preclude the proposed Site 7 restoration project from the Lower Cedar River Chinook Salmon Habitat Restoration Assessment 10 Habitat Response to Muckleshoot Comments Cedar River Apartments July 24, 2020 Page 5 Restoration Site Potential and Feasibility Analysis Report (Herrera 2015). This project and the larger Lower Cedar River Chinook Salmon Habitat Restoration Report/plan (now part of the larger WRIA 8 plan) were not considered in any of the project application documents we reviewed to date. As a result, the restoration project has not been considered in the design and evaluation of project impacts. This is another reason why an EIS should be done that could evaluate a development proposal that accommodates the restoration project. Response: During its initial review of the proposed project, the City of Renton contemplated a limited-scope EIS to fully address concerns associated with traffic and the stability of the existing wall. Traffic concerns raised by the City and its consultant have been fully addressed in subsequent Transportation Impact Analyses prepared by William Popp & Associates. Additionally, the City expressly requested information related to the soundness/integrity of the existing wall. The intent of the request from the City was to demonstrate whether the existing wall would protect the proposed project for the life of the development. As described in the previous response, the various prepared studies demonstrate that the wall in fact, would protect the project over the course of its life. No other issues, beyond these two, were identified by the City as potentially needing further SEPA review. Thus, an EIS is not required because the project does not pose significant adverse impacts. Retention of the existing wall on the site, proven to be sound and of full integrity, combined with full adherence to the City’s shoreline buffer requirements, represents a logical project proposal. As described in the previous response, extensive consideration has already been given to the recommendations within the Herrera Report regarding full restoration of the on-site stream corridor. Upon this consideration, the most feasible option was selected: retention of the existing wall without any new shoreline stabilization measures. This option allows for private redevelopment of the site, while also providing a fully restored stream buffer, in compliance with the City’s shoreline master program requirements. A more comprehensive restoration alternative is financially infeasible due to costs associated with excavation (that are compounded by contaminated groundwater). Therefore, preparation of an EIS, which is not warranted for this Project, would not result in evaluation of reasonable project alternatives that accommodate the full restoration project conceptualized in the Herrera Report. Analysis of reasonable alternatives in an EIS is limited to “action[s] that could feasibly attain or approximate a proposal's objectives.” (WAC 197-11-786). The full restoration plan was recommended in conjunction with public acquisition of the site for park purposes, which did not occur. Response to Muckleshoot Comments Cedar River Apartments July 24, 2020 Page 6 Although full wall removal and restoration is not financially feasible, the proposed project does take steps to restore the stream corridor to the extent feasible. This includes removing the concrete wash ponds, lowering the existing concrete retaining wall in places, and restoring the entire 100-foot shoreline buffer with native vegetation. Existing environmental conditions Has the site been fully evaluated to ensure there are no environmental hazards, toxics, groundwater contamination that needs to be addressed before the site can be redeveloped? The former concrete settling ponds still exist on site from the available photo record. Again, an EIS would help discern these issues further and evaluate how different development alternatives would affect or be affected by these conditions if they exist. Response: Yes, the site has been evaluated for environmental hazards and groundwater contamination is known to exist on the site. A Voluntary Cleanup Program was prepared for the site and has been fully implemented by the owner. In addition, the owner has entered into an Environmental Covenant with Ecology which will ensure that only with Ecology approval will any contaminated soils be exposed. The Environmental Covenant outlines the goal of containing contaminated groundwater beneath the Property. Contact with contaminated groundwater will be prevented by placing clean inert fill material within the settling pond. Per the Environmental Covenant, groundwater is not to be extracted for any purpose other than investigation, monitoring, or remediation and any groundwater extracted would be considered potentially contaminated. Groundwater monitoring will be established along the western property boundary and stormwater infiltration will not be allowed in an effort to minimize the potential for mobilization of contaminants. A ‘No Further Action’ letter was issued in October 2019 and is included with this letter. The applicant has carefully designed the proposal, including shoreline buffer restoration, to account for all environmentally hazardous constraints. As previously mentioned, the wall is sound and doesn’t need to be removed, improved, or repaired. If voluntary removal of the wall were to occur, the presence of site contaminants would necessitate further excavation/cleanup on a scale not contemplated by the Herrera Report, nor within the financial means of the applicant. Therefore, the only feasible alternative is to retain the wall in its existing condition while fully complying with City’s shoreline buffer requirements. Stormwater Management Response to Muckleshoot Comments Cedar River Apartments July 24, 2020 Page 7 a. Regardless of development alternatives, we understand that any redevelopment project would be exempt from any stormwater detention requirements and would be allowed to discharge stormwater directly to the Cedar River. From our review of the basis of this decision in WDOE’s Stormwater Management Manual for Western Washington, there was no biological considerations for this decision and no evaluation of its potential impact on treaty-protected resources, including ESA listed Chinook and Steelhead. The issue is that the stormwater will be discharged into margin areas of the Cedar River that are important to juvenile salmon for their health and survival. The project needs to be modified by requiring detention and enhancement of the river habitat where the outfalls will discharge stormwater to reduce impacts from increases in water velocities that exceed those necessary for juvenile salmon to maintain station, feed, avoid predators, etc. and not get flushed downstream prematurely. Response: Stormwater infiltration is not allowed to occur due to the presence of on-site groundwater contamination and the restrictions of the Environmental Covenant with Ecology. However, runoff from the western, central, and eastern courtyards will be directed through non-infiltrating vegetated swales prior to discharge into the Cedar River. The courtyards are comprised of landscaped and hardscaped areas limited to pedestrian use only (no pollution generating surfaces). The vegetated swales will slow and clean runoff prior to release into the river. The addition of woody plant material to the shoreline buffer, and throughout the landscaped upland portions of the site, is also expected to improve the degree of rainwater interception and year-round water uptake within the biomass of the plants on-site. As for pollution generating surfaces, stormwater from roofs and parking lots is to be collected, filtered, and then held in vaults with built-in flow control. From the vaults, stormwater will enter into the municipal stormwater system. b. For the proposed project or any other alternative, the redeveloped site also needs to provide enhanced treatment methods for its stormwater to reduce metals and oil discharges in stormwater that adversely affect salmon. See https://www.govlink.org/watersheds/8/pdf/NOAA_stormwater_research_references.pdf for a list of references on this topic. Response: Stormwater discharging to the Cedar River will come only from non- pollution generating surfaces and will be treated in non-infiltrating stormwater swales prior to entering the river at the edge of the vegetated buffer. Proposed swales will slow flows and allow for biofiltration within the buffer, further reducing the likelihood of metals or oils reaching the river. Response to Muckleshoot Comments Cedar River Apartments July 24, 2020 Page 8 Artificial Lighting The project’s artificial lighting details need to be fully discussed including how artificial lighting will be designed/managed to avoid increasing predation risks for juvenile salmon in the Cedar River. Response: A fully vegetated 100-foot buffer is to be provided between the Cedar River and upland development. No artificial lighting is proposed within the buffer. Exterior lighting upland of the buffer will be that typical of residential buildings and associated structures, intended to improve safety after daylight hours. All project lighting will be designed in compliance with the requirements of the City’s shoreline master program which requires that all nighttime lighting be designed to avoid or minimize interference with aquatic life cycles through avoidance of light sources that shine directly onto the water. Exterior lighting fixtures shall include full cut off devices such that glare or direct illumination does not extend into water bodies. Lighting shall include timers or other switches to ensure that lights are extinguished when not in use (4-3-090D.2.e.iii). Sincerely, Kenny Booth, AICP Senior Planner