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HomeMy WebLinkAboutECF_SEPA_Checklist_210420_v1 SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 1 of 28 SEPA Environmental Checklist Purpose of checklist: Governmental agencies use this checklist to help determine whether the environmental impacts of your proposal are significant. This information is also helpful to determine if available avoidance, minimization, or compensatory mitigation measures will address the probable significant impacts or if an environmental impact statement will be prepared to further analyze the proposal. Instructions for applicants: This environmental checklist asks you to describe some basic information about your proposal. Please answer each question accurately and carefully, to the best of your knowledge. You may need to consult with an agency specialist or private consultant for some questions. You may use “not applicable” or "does not apply" only when you can explain why it does not apply and not when the answer is unknown. You may also attach or incorporate by reference additional studies reports. Complete and accurate answers to these questions often avoid delays with the SEPA process as well as later in the decision-making process. The checklist questions apply to all parts of your proposal, even if you plan to do them over a period of time or on different parcels of land. Attach any additional information that will help describe your proposal or its environmental effects. The agency to which you submit this checklist may ask you to explain your answers or provide additional information reasonably related to determining if there may be significant adverse impact. Instructions for Lead Agencies: Please adjust the format of this template as needed. Additional information may be necessary to evaluate the existing environment, all interrelated aspects of the proposal and an analysis of adverse impacts. The checklist is considered the first but not necessarily the only source of information needed to make an adequate threshold determination. Once a threshold determination is made, the lead agency is responsible for the completeness and accuracy of the checklist and other supporting documents. Use of checklist for nonproject proposals: For nonproject proposals (such as ordinances, regulations, plans and programs), complete the applicable parts of sections A and B plus the supplemental sheet for nonproject actions (part D). Please completely answer all questions that apply and note that the words "project," "applicant," and "property or site" should be read as "proposal," "proponent," and "affected geographic area," respectively. The lead agency may exclude (for nonprojects) questions in Part B — Environmental Elements—that do not contribute meaningfully to the analysis of the proposal. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 2 of 28 A. Background 1. Name of proposed project, if applicable: Madsen Creek Flooding Improvement Project 2. Name of applicant: City of Renton, Surface Water Utility Engineering 3. Address and phone number of applicant and contact person: Amanda Pierce, PE City of Renton Surface Water Utility Engineering 1055 South Grady Way Renton, Washington 98057 Office: 425-430-7205 Cell: 801-372-4682 apierce@rentonwa.gov 4. Date checklist prepared: March 10, 2021 5. Agency requesting checklist: City of Renton 6. Proposed timing or schedule (including phasing, if applicable): Construction in Summer/Fall 2021 7. Do you have any plans for future additions, expansion, or further activity related to or connected with this proposal? If yes, explain. Ongoing maintenance activities for the high flow bypass channel will be required, due to continuous deposition of sediment. 8. List any environmental information you know about that has been prepared, or will be prepared, directly related to this proposal. ● Environmental Assessment Report—Madsen Creek Improvement Project (Herrera Environmental Consultants, Inc. [Herrera], September 2018) ● Mitigation Plan – Madsen Creek Flooding Improvement Project (Herrera, March 2021) ● Letter to Amanda Pierce, City of Renton Public Works, dated May 4, 2020 RE: Arborist survey of trees potentially impacted by the project work along Madsen Creek High Flow Bypass channel (Herrera, 2020) ● Technical Memorandum, dated March 10, 2021, to Amanda Pierce, City of Renton, RE: Summary of Hydraulic Modeling for Design and Permitting of Flood Control Improvements and Evaluation of Floodplain Fill Mitigation (Watershed Science & Engineering [WSE] and Herrera, 2021) ● WSE. 2019. Final Lower Madsen Creek Existing Conditions Flood & Sediment Assessment. Prepared for the City of Renton Public Works. Watershed Science & Engineering, Seattle, Washington. March 20, 2019. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 3 of 28 9. Do you know whether applications are pending for governmental approvals of other proposals directly affecting the property covered by your proposal? If yes, explain. None are known. 10. List any government approvals or permits that will be needed for your proposal, if known. City of Renton: ● Grading Permit ● Land Use Permit ● Environmental Review ● Critical Areas Review Implementation of flood risk reduction improvements is considered exempt from City of Renton (City) critical areas permitting where habitat enhancement and restoration at a one-to-one ratio is provided. A letter of exemption for critical areas permitting for the project has been prepared for authorization by the City administrator according to the Section 4-3-050C 2-3 of City of Renton Municipal Code. ● Compliance with FEMA National Flood Insurance Program Some of the proposed improvements are within mapped floodplain areas. As part of the City’s compliance with the National Flood Insurance Program (NFIP), any proposed construction within a floodplain recognized by the Federal Emergency Management Agency (FEMA) must document potential effects on species listed for protection under the federal Endangered Species Act, and associated mitigation measures to reduce and eliminate adverse effects on those species. A “No Effect Letter” has been prepared for this project to document compliance. Additionally, in relation to the City’s compliance with NFIP guidance, the City requires compensatory mitigation where existing flood storage is displaced by proposed site development. Proposed work at Site 4 extends into unincorporated King County. King County project authorization will include the following: ● Critical Areas Review ● Clearing and Grading Permit ● Shoreline Permit (or Exemption) ● Flood Hazard Certification Work at all four sites requires a Hydraulic Project Approval (HPA) by the Washington Department of Fish and Wildlife because altering how flood flow is conveyed through the Madsen Creek system can affect in-channel habitat conditions. 11. Give brief, complete description of your proposal, including the proposed uses and the size of the project and site. There are several questions later in this checklist that ask you to describe certain aspects of your proposal. You do not need to repeat those answers on this page. (Lead agencies may modify this form to include additional specific information on project description.) SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 4 of 28 The City of Renton proposes to reduce the risk of flooding of residential properties and local streets adjacent to Madsen Creek just upstream of its confluence with the Cedar River. The work is being funded by a King County Flood Control District Flood Reduction Grant. King County completed several modifications within the drainage basin in the 1970s and 1980s to address flooding and sedimentation, including realignment of the creek channel and construction of a sediment basin and a high flow bypass channel. Despite these modifications, flooding still occurs south of State Route (SR) 169 in the Wonderland Estates public housing development and on private properties (owned by a church and a single-family residence), and north of SR 169 on several residential parcels east of 149th Avenue Southeast. Based on a review of the existing site conditions and an evaluation of alternative measures, the City proposes to reduce the occurrence of overbank flood flow at four locations (Sites 1–4) (Figure 1). Construction at all four sites is proposed in summer 2021, with planting to follow a few months later in the fall. Sites 3 and 4 are associated with the Madsen Creek low flow channel (which flows year-round) and Sites 1 and 2 are along the Madsen Creek high flow bypass channel, which is ephemeral and only conveys flow during the peak of moderate and greater flood events in Madsen Creek. Three of the sites (Sites 1, 2, and 3), representing about 0.6 acres in total area, are located entirely within the jurisdiction of the City of Renton. Project work at Site 4, including project mitigation planting areas, represents 380 square feet within the City of Renton and 2,270 square feet within King County. The total area represents 2,650 square feet (0.06 acres). Preliminary project design plans are attached (Herrera 2021). Work at Site 1 will create an armored overflow spillway for the existing sediment basin to reliably direct overflows into the Madsen Creek high flow bypass channel. The existing sediment basin does not have a defined spillway to prevent flows from overtopping the north bank and coursing into the King County Housing Authority’s Wonderland Estates residential development. Overtopping of the sediment basin could occur if the outlet culvert to the high flow bypass channel is blocked by debris or does not have the ability to handle a flood wave moving through the sediment basin. Project work at this site will assure that, when a major flood flow enters the sediment basin, the embankment forming the north side of the sediment basin reduces the risk of being overtopped. The new spillway and surrounding soil and rock fill to taper the existing maintenance access road elevation on all sides to create a smooth driving surface over the spillway represents approximately 5,300 square feet (0.12 acres) in total area. The majority of it will be constructed over an existing gravel access roadway, thus limiting impacts to City regulated riparian buffer areas. Proposed native vegetation installation will enhance buffer functions at a 1:1 mitigation ratio. None of the proposed work at Site 1 is situated within the 100-year floodplain of the Cedar River. The Site 2 project area is within, and adjacent to, the high flow bypass channel and extends for a channel length of approximately 550 feet upstream of SR 169. The high flow bypass channel currently experiences a combination of sediment accumulation in the channel bed and low ground on the right (east) bank, limiting flood flow conveyance capacity. During specific flood events, high flows overtop the right bank and overland flow occurs to the east through an open field and into the Madsen Creek low flow channel; exacerbating flooding of residential areas adjacent to the low flow channel downstream. The original design of the high flow bypass channel was intended to prevent such flooding. Work at Site 2 will include sediment removal in the bottom of the high flow bypass channel to restore its originally constructed dimensions, minor widening of the channel at that original bottom elevation (by approximately 2.25 feet to the east side) to increase flood storage and conveyance capacity, and raising the right (east) bank with a berm to effectively contain the 100-year SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 5 of 28 flood. Sediment removal and local widening in the channel will occur for a length of approximately 500 linear feet. The berm along the top of the widened right (east) bank will be approximately 400 feet long to eliminate the low spot. The maintenance access road, located on the west side of the high flow bypass channel, will not be modified, other than to restore a smooth gravel surface upon completion of construction. These actions are proposed to ensure that the Madsen Creek 100-year peak flood flow, and flows of lesser magnitudes, are conveyed within the high flow bypass channel directly to the Cedar River, as intended in the original high flow bypass design. A portion of the Site 2 work, representing 3,485 square feet (0.08 acres), will occur within the 100-year floodplain. This floodplain is associated with Cedar River overbank flooding and resultant backwater that occurs in Madsen Creek. Slightly increasing the width of the high flow bypass channel will offset the flood storage displaced by berm and floodwall construction in floodplain areas at Sites 3 and 4. Impacts to the high flow bypass channel and its critical area buffer will be mitigated through the removal of invasive vegetation and the installation of native plants within 16,850 square feet (0.39 acres) of protected riparian buffer area. Site 3 is adjacent to the south side of the SR 169 right-of-way, fronting Wonderland Estates and a single-family residence northeast of Wonderland Estates. Proposed Site 3 work includes the construction of a new berm along the left (south) bank of the Madsen Creek low flow channel on the Wonderland Estates property and a low floodwall made of concrete masonry units (or comparable material) on City-owned land (in the SR 169 right-of-way) adjacent to the south bank of the low flow channel on the north side of the single-family residence’s lawn, with the floodwall connecting to the berm near the shared property line for continuous flood containment. The wall and berm will extend westerly from high ground near the culvert that conveys the Madsen Creek low flow channel beneath the high flow bypass channel for a total length of 210 feet, tying into high ground on the west side of the entrance of the existing Madsen Creek low flow culvert under SR 169. Site 3 improvements will include 1,820 square feet (0.04 acres) of existing vegetation clearing, berm and floodwall construction, and riparian vegetation restoration in the berm area. The footprint area of the berm within the 100-year floodplain will be 1,120 square feet (0.026 acres). The footprint area of the floodwall within the 100-year floodplain will be approximately 60 square feet (0.001 acres). All disturbed buffer areas on Wonderland Estates property will be restored with native vegetation prior to project completion. Creek buffer disturbance associated with floodwall construction near the bank of the Madsen Creek low flow channel will be mitigated via additional planting at the south end of Site 2. Site 4 is located north of SR 169 between the Cedar River Trail and a single-family residence (15214 149th Avenue Southeast). The existing nonnative riparian vegetation at this site is in poor condition and the right (north) bank does not contain Madsen Creek flood flows. Site 4 improvements will impact an area of approximately 1,435 square feet (0.033 acres). Improvements involve removing concrete blocks and soil surrounding them on the right bank, raising the right (north) bank of the low flow channel with an earthen berm, removing existing vegetation necessary for construction, and adding native riparian plantings along both sides of Madsen Creek. The earthen berm will prevent overtopping of the right bank in of the 100-year flood event in Madsen Creek when the Cedar River is not at extreme flood stage, reducing flooding of residential properties to the north. The Cedar River 100-year peak flood elevation is higher than the top elevation of the berm to be constructed. Site 4 extends beyond Renton city limits into unincorporated King County. Mitigation to restore disturbed buffer areas will be accomplished through the removal of nonnative vegetation and the installation of native plants. Removal and replacement are proposed at ratios of 1:1 and 3:1, as required per City of Renton and King County regulations, respectively. Cedar River Madsen Creek High Flow ChannelKing County Madsen Creek Low Flow Cha n n e l King County Ron Regis Park New LifeChurch Elliott Bridge ReachMitigation Site WonderlandEstates SedimentBasin Wetland E(2018) Wetland F(2018)Renton SE RENTON- M A P L E V A L L E Y R D ( S R - 1 6 9 )MAPLE DRSE JO N E S R D 145TH AVE SE142 ND P L SE 146THPLSESE 1 5 7 THPL154TH PL SESE 155TH PL 143RD A VESE150THLNSE152ND AVE SESE 154TH ST SE 153RD PL 1 4 0 T H WA Y S E149TH AVE SEOAK DRPINE DRSEJONESPL Site 4 Site 3 Site 2 Site 1 0 400 800200Feet K:\Projects\Y2018\18-06779-001\Project\Report\Figure2_SiteMap_letter_less.mxd Figure 1.Site Map for the Madsen Creek Flood Reduction Improvements. E Legend 2018 EnvironmentalAssessment Report study area Approximate locationof proposed projectsites Jurisdiction boundary Parcel Inundation boundary Wetland area (HEC, 2018) SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 7 of 28 12. Location of the proposal. Give sufficient information for a person to understand the precise location of your proposed project, including a street address, if any, and section, township, and range, if known. If a proposal would occur over a range of area, provide the range or boundaries of the site(s). Provide a legal description, site plan, vicinity map, and topographic map, if reasonably available. While you should submit any plans required by the agency, you are not required to duplicate maps or detailed plans submitted with any permit applications related to this checklist. The project area is located within the Renton city limits and unincorporated King County, in Sections 22 and 23 of Township 23 North, Range 05 East of the Willamette Meridian (Figure 1 attached). The Madsen Creek drainage basin is within the Lower Cedar River Watershed and Water Resource Inventory Area (WRIA) 8: Cedar-Sammamish. Sites 1 (sediment basin spillway) and 2 (along the high flow bypass channel) are located in a permanent easement along the western edge of a 55.5-acre property owned by New Life Church@Renton, King County Tax Parcel #2323059021, located at 15711 152nd Avenue Southeast within the City of Renton. Proposed project work at Site 3 will occur within the Maple Valley Road (SR 169) right-of-way, which is owned by the City, and on land at the northern boundary of the Wonderland Estates public housing development (Parcel #2323059020, comprising approximately 12.2 acres, owned and operated by the King County Housing Authority) located at 14645 SE Renton-Maple Valley Road. Project work at Site 4 will occur along the north side of the Cedar River Trail in an easement on BNSF Railway land and on the approximately 1.48-acre private residential parcel, #2323059070, located at 15214 149th Avenue SE in unincorporated King County. B. Environmental Elements 1. Earth a. General description of the site: (circle one): Flat, rolling, hilly, steep slopes, mountainous, other _____________ b. What is the steepest slope on the site (approximate percent slope)? The topography of the study area is generally flat due to its landscape position within the Cedar River Valley and adjacent to a highway. c. What general types of soils are found on the site (for example, clay, sand, gravel, peat, muck)? If you know the classification of agricultural soils, specify them, and note any agricultural land of long-term commercial significance and whether the proposal results in removing any of these soils. Three soil series are mapped within the project area: Alderwood and Kitsap soils, very steep; Newberg silt loam; and Puyallup fine sandy loam. The soil in most of the study area is composed of Newberg silt loam while a smaller portion near the Cedar River is mapped SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 8 of 28 as Puyallup fine sandy loam. Proposed sediment removal from the high flow bypass channel at Site 2, as a stormwater facility maintenance measure, will not impact any agriculturally or commercially significant soil. d. Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe. No. e. Describe the purpose, type, total area, and approximate quantities and total affected area of any filling, excavation, and grading proposed. Indicate source of fill. The purpose of the project is to reduce flooding. Work at all four project sites will result in the net removal of 9.5 cubic yards of soil from the 100-year floodplain, not including excavation proposed to restore the originally constructed dimensions of the Madsen Creek high flow bypass channel, thus maintaining flood storage capacity within the basin. Most of the soil removal will occur via dredging and widening along 500 linear feet of the high flow bypass channel at Site 2. Total project work, including fill and grading activities at elevations above the 100-year floodplain, represents a net fill of approximately 40 cubic yards of material. The volumes of cut and fill activities proposed, within and outside of the floodplain, for each of the project site areas are presented in the following table: Table 1. Excavation and Fill Activities for Proposed Madsen Creek Flooding Improvements. Site ID Within 100-Year Floodplain (cubic yards) Outside 100-Year Floodplain (cubic yards) Total (cubic yards) Excavation (Cut) Fill Cut Fill Site 1 Not Applicable 20 145 125 Fill Site 2 125 0 203 170 170 Fill 328 Cut Net: -158 Net Floodplain: -125 Net: -33 Site 3 0 33 0 22 55 Fill Site 4 0 38 0 0 38 Fill NET TOTAL: 60 (Fill) Site 1 will involve constructing an armored spillway and raising the north and east bank berms of the existing sediment basin. The spillway will convey overflows into the high flow bypass channel and will require an estimated 145 cubic yards of new ballast rock (large gravel and smaller aggregate), Class A rock for erosion and scour protection (similar in size to riprap), and compacted earth fill beneath the rock armoring. The majority of the new spillway and raised ground surrounding it, representing approximately 5,300 square feet in total area will be constructed over an existing gravel roadway used for access to the sediment basin. The spillway’s buffer encroachment, beyond the existing roadway, represents 1,160 square feet of disturbed area. The existing roadside vegetation, where the spillway buffer encroachment will occur, consists of mowed grasses and weedy herbaceous plants that provide buffer functions at low levels. Proposed mitigation for the spillway’s buffer encroachment will include the installation of 1,160 square feet of native trees, shrubs, and ground cover plants within the buffer adjacent to the spillway’s outfall into the high flow SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 9 of 28 bypass channel. The sediment basin bank berms will be raised slightly to an elevation of 126 feet (North American Vertical Datum of 1988 [NAVD88) on the north and east sides, approximately 2 feet above the existing grade at elevation 124 feet (NAVD88). The new spillways will have a crest elevation of 124 feet. All fill activities at Site 1 will occur at elevations outside the mapped 100-year floodplain. Site 2 work will involve sediment removal and channel geometry restoration within the bankfull width of the high flow bypass channel. The bankfull width will be widened to approximately 16.25 feet from the existing bankfull width of 14 feet to create additional flood storage (compensating for displaced flood storage at Sites 3 and 4). The bottom of the 5-foot-wide channel will be lowered by approximately 1 foot, on average, from the existing grade to restore the originally constructed channel dimensions. The right (east) bank will be raised with an earthen berm for a length of approximately 430 linear feet. The berm will consist of low permeability imported soil fill dressed with topsoil for planting, with the top of the berm being up to 3 feet above the existing grade. The berm will have a top width of 4 feet and 2H:1V side slopes. Within the mapped floodplain, the volume of fill (zero) and excavation activities at Site 2 represents a net total excavation of 71 cubic yards, not including excavation to restore the original high flow bypass channel dimensions. The amount of excavation to restore the original channel dimensions will be a total of approximately 200 cubic yards, of which approximately 54 cubic yards will be within the mapped floodplain. Project-associated excavation (203 cubic yards) and fill (170 cubic yards) at elevations above the 100-year flood, represents a net excavation of 33 cubic yards. The expanded flood flow capacity of the high flow bypass channel will provide 6 inches of freeboard above the 100-year flood elevation, assuring that the project will have long-lasting performance value, thus assuring that the project will have no adverse flooding effects on nearby land. The new berm proposed at Site 3 will require an estimated total of 53 cubic yards of fill to raise the ground surface for a length of 120 linear feet adjacent to the Madsen Creek low flow channel. The new floodwall proposed at Site 3 will likely be made of concrete masonry units (or similar precast concrete blocks), and will have a volume of up to 3 cubic yards above existing ground along a length of 90 feet between the Madsen Creek low flow channel bank and an existing evergreen hedge (arborvitae). The berm and floodwall footprint represents a total area of 1,180 square feet. The top of the flood control berm and wall will be at 103 feet in elevation (NAVD88); which on average is 1.5 feet higher than the existing grade. The proposed berm top width is 4 feet; the bottom width varies due to the 2H:1V slope transition to existing ground. The proposed wall width will be 8 inches, with vertical sides. Minimal or as needed excavation is proposed in association with the project work to transition the base of the berm into native soil and to smooth the ground surface at the base of the wall. The estimated volume of berm and wall fill to be placed below the 100-year flood elevation is 33 cubic yards. Site 4 berm construction will require vegetation clearing, removal of existing concrete blocks, and approximately 38 cubic yards of net fill placement above existing grade. The base of the berm will be excavated into native soil, and the new berm will be made with low permeability soil, dressed with topsoil for successful riparian vegetation growth. All of the proposed berm fill will be placed within the 100-year floodplain. The total footprint of fill for berm construction is 1,135 square feet, and an additional 300 square feet will be disturbed for construction access. The project area at Site 4 is 380 square feet within the City of SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 10 of 28 Renton jurisdiction and the remaining 1,055 square feet of construction area is within unincorporated King County. All imported fill will be acquired from a permitted facility. f. Could erosion occur as a result of clearing, construction, or use? If so, generally describe. Potential for erosion exists during construction of the sites that will entail excavation (Sites 2, 3 and 4) as a result of exposed soils during precipitation events. If the ground surface is not stabilized at the completion of grading work at Site 2 with a sufficient erosion control material, erosion could occur during the ensuing wet season when flows occur in the high flow bypass channel. g. About what percent of the site will be covered with impervious surfaces after project construction (for example, asphalt or buildings)? The only impervious surfaces that will exist in the four project site areas following construction are associated with the existing maintenance access road at Sites 1 and 2 (which will not be increased in surface area), the rock for the Site 1 spillway extending beyond the edges of the existing access road in that area, and the top surface of the new floodwall at the east end of Site 3. These surfaces equate to approximately 27 percent of the total project area. h. Proposed measures to reduce or control erosion, or other impacts to the earth, if any: Implementation of best management practices (BMPs) such as defining clearing limits and installing stabilized construction entrances, wattles and silt fencing will prevent and minimize transport of eroded soil during construction, and mulch or other temporary cover on freshly built earthen berms will prevent erosion while new vegetation plantings become established. A biodegradable erosion control blanket is proposed for disturbed ground along the high flow bypass channel at Site 2 prior to seeding, to resist erosion when streamflows are routed through the bypass channel in the ensuing wet season. Seeding with an erosion control seed mix will stabilize disturbed areas immediately following construction completion in advance of riparian planting work. 2. Air a. What types of emissions to the air would result from the proposal during construction, operation, and maintenance when the project is completed? If any, generally describe and give approximate quantities if known. Airborne dust could occur during excavation and installation of backfill materials. The operation of diesel and gas-powered construction equipment will also be a source of emissions, typical of small-scale construction sites. After construction, the project will not generate any air emissions. b. Are there any off-site sources of emissions or odor that may affect your proposal? If so, generally describe. No. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 11 of 28 c. Proposed measures to reduce or control emissions or other impacts to air, if any: None. 3. Water a. Surface Water: 1) Is there any surface water body on or in the immediate vicinity of the site (including year-round and seasonal streams, saltwater, lakes, ponds, wetlands)? If yes, describe type and provide names. If appropriate, state what stream or river it flows into. The project site includes Madsen Creek, a perennial Type-F (Fish bearing) stream and is associated City and King County regulated 115-foot-wide protective buffer areas. The high flow bypass channel is ephemeral; as it only contains flows during the 2-year or larger flood events. The high flow bypass is mapped by the City of Renton as a Type-F water but is managed by the City as a stormwater facility. The Washington State Department of Natural Resources (DNR) and the Washington Department of Fish and Wildlife (WDFW) do not consider any portion of the high-flow bypass as Type-F or fish bearing. The DNR and WDFW classify the high flow bypass as a Type N stream. Site 1 is adjacent to an inline sediment settling basin with Madsen Creek and is located at the upstream end of the high flow bypass channel. Site 2 is in and along the high flow bypass channel. Sites 3 and 4 are located along the Madsen Creek low flow channel and two associated riverine wetlands. All surface waters in the project area flow into the Cedar River, which is more than 1,000 feet downstream of each proposed work site. 2) Will the project require any work over, in, or adjacent to (within 200 feet) the described waters? If yes, please describe and attach available plans. All work will occur adjacent to or within 200 feet of the described waters. Work within the 100-year floodplain of the Cedar River and Madsen Creek is proposed at Sites 2, 3 and 4. The construction of an armored spillway at Site 1 will extend slightly into the high flow bypass channel and sediment removal at Site 2 will occur below the ordinary high water mark (OHWM) of the high flow bypass channel. No other surface waters will be directly impacted by the project. 3) Estimate the amount of fill and dredge material that would be placed in or removed from surface water or wetlands and indicate the area of the site that would be affected. Indicate the source of fill material. The armored spillway at Site 1 will extend into the high flow bypass channel requiring up to 10 cubic yards of fill within 100 square feet below the OHWM. At Site 2, proposed in-stream sediment removal below the OHWM will entail excavation of approximately 110 cubic yards within a footprint area of 4,276 square feet. This excavation will occur in the dry season when there is no flow in the bypass channel. No construction work will occur within delineated wetlands. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 12 of 28 4) Will the proposal require surface water withdrawals or diversions? Give general description, purpose, and approximate quantities if known. Construction work in the high flow bypass channel at Site 2 will not require water to be diverted because all work will occur during the dry season when no flows are present in the high flow bypass channel. 5) Does the proposal lie within a 100-year floodplain? If so, note location on the site plan. Portions of proposed project Sites 2, 3 and 4 are within mapped 100-year floodplain areas (see Figure 2). The total project work will result in the removal of 125 cubic yards of soil materials within the 100-year floodplain, of which 54 cubic yards represents restoring the originally constructed bypass channel dimensions. Minor widening of the high flow bypass channel will create 71 cubic yards of flood storage capacity, offsetting the 71 cubic yards of fill to be placed within floodplain areas at Sites 3 and 4, thus maintaining overall flood storage capacity within the basin, as detailed in Section B.1.e of this Checklist. 6) Does the proposal involve any discharges of waste materials to surface waters? If so, describe the type of waste and anticipated volume of discharge. No. b. Ground Water: 1) Will groundwater be withdrawn from a well for drinking water or other purposes? If so, give a general description of the well, proposed uses and approximate quantities withdrawn from the well. Will water be discharged to groundwater? Give general description, purpose, and approximate quantities if known. No. 2) Describe waste material that will be discharged into the ground from septic tanks or other sources, if any (for example: Domestic sewage; industrial, containing the following chemicals; agricultural; etc.). Describe the general size of the system, the number of such systems, the number of houses to be served (if applicable), or the number of animals or humans the system(s) are expected to serve. None. c. Water runoff (including stormwater): 1) Describe the source of runoff (including storm water) and method of collection and disposal, if any (include quantities, if known). Where will this water flow? Will this water flow into other waters? If so, describe. Existing stormwater runoff occurs at each of the proposed work sites, and additional runoff may enter work areas from adjacent roads (SR 169 and 149th Avenue Southeast), the Cedar River Trail, and the parking area at the north edge of the Wonderland Estates property. All runoff will discharge directly into the high flow bypass SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 13 of 28 and low flow channels of Madsen Creek. No additional storm water flows into the Madsen Creek system will result from this project. 2) Could waste materials enter ground or surface waters? If so, generally describe. No. 3) Does the proposal alter or otherwise affect drainage patterns in the vicinity of the site? If so, describe. The proposal will not alter stormwater runoff patterns in the project area. The proposal modifies the inlet to the high flow bypass channel (at Site 1), assuring predictable Madsen Creek outflows from the sediment basin into the high flow bypass channel during extreme flood events. This modification will not increase or reduce the amount of Madsen Creek flow exiting the sediment basin during flood events, but it will assure that extreme flood flows cannot overtop the basin to the northwest and enter the Wonderland Estates residential property. The proposal will reduce the occurrence of overbank creek flooding on several nearby properties and 149th Avenue Southeast. d. Proposed measures to reduce or control surface, ground, and runoff water, and drainage pattern impacts, if any: None. Cedar River Madsen Creek High Flow ChannelKing County Madsen Creek Low Flow Cha n n e l King County Ron Regis Park New LifeChurch Elliott Bridge ReachMitigation Site WonderlandEstates SedimentBasin Wetland E(2018) Wetland F(2018)Renton SE RENTON- M A P L E V A L L E Y R D ( S R - 1 6 9 )MAPLE DRSE JO N E S R D 145TH AVE SE14 2 ND P L SE 146THPLSESE 1 5 7 T HPL154TH PL SESE 155TH PL 143RD A VESE150THLNSE152ND AVE SESE 154TH ST SE 153RD PL 1 4 0 T H WA Y S E149TH AVE SEOAK DRPINE DRSEJONESPL Site 4 Site 3 Site 2 Site 1 0 400 800200Feet K:\Projects\Y2018\18-06779-001\Project\Report\Figure3_MappedFloodplain_letter.mxd Figure 2.Mapped 100-Year Floodplain. E Legend Approximate locationof proposed projectsites Jurisdiction boundary Parcel Inundation boundary Wetland area (HEC, 2018) 100-yr Floodplain SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 15 of 28 4. Plants a. Check the types of vegetation found on the site: _X__deciduous tree: alder, maple, aspen, other _X__evergreen tree: fir, cedar, pine, other _X__shrubs _X__grass ____pasture ____crop or grain ____Orchards, vineyards or other permanent crops. _X__wet soil plants: cattail, buttercup, bullrush, skunk cabbage, other ____water plants: water lily, eelgrass, milfoil, other ____other types of vegetation b. What kind and amount of vegetation will be removed or altered? Site 1 construction will have impacts to herbaceous and nonnative vegetation. Dredging at Site 2 will remove grasses, including invasive reed canarygrass and other weedy herbaceous vegetation growing along the high flow bypass channel. Construction to raise the eastern bank of the high flow bypass will require the removal of six of the total seven existing multi-stemmed deciduous trees present at the site. The results of an arborist survey of trees potentially impacted by the project work at Site 2 are documented in a letter to Amanda Pierce, City of Renton Public Works Department, dated May 4, 2020 (Herrera 2020). The six trees proposed for removal include one native red alder (Alnus rubra), reported in poor health, two nonnative Norway maples (Acer platanoides) in good and fair condition, one common hawthorn (Crataegus monogyna) that is in excellent condition, one cherry (Prunus sp.) that is in poor to fair condition and one Oregon ash (Fraxinus latifolia) reported in good condition. A big-leaf maple (Acer macrophyllum), reported to be in excellent condition near the southern end of the Site 2 work area, will be retained and protected from construction activities. With the exception of the Oregon ash measured as 5.8 inches in caliper, the trees at Site 2 meet the City of Renton’s following tree size definitions: greater than 8-inch caliper [equivalent to diameter at breast-height (dbh)], individual measurements of stem diameter at 4.5 feet above ground level) for alder and cottonwood and greater than 6-inch caliper for other species. Trees to be removed at Site 2 will be replaced at a ratio greater than 2:1 within a native vegetation planting area adjacent to, and south of the constructed berm. Site 3 construction work will remove nonnative and herbaceous vegetation and some landscaped shrubs, including native red-osier dogwood (Cornus alba). Installation of the low concrete floodwall at the east end of this site will require pruning branches at the base of an arborvitae hedge, for a height of approximately 2 feet above the ground surface. Site 4 construction work will remove forest vegetation that is primarily comprised of native Pacific and Sitka willows (Salix lucida ssp, lasiandra, S. stichensis). red-osier dogwood, salmonberry, spiraea (Spiraea douglasii), nonnative Himalayan blackberry and English Ivy (Hedera helix) vines and invasive herbaceous plants, including reed canarygrass. Existing cottonwoods and alders adjacent to the Cedar River Trail will be retained and protected from construction activities. No direct impacts to the Category II riverine PFO Wetland E SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 16 of 28 that parallels the creek and SR 169 are proposed. Native plants are proposed for installation on and adjacent to the constructed flood control berm. Residential lawn and nonnative Himalayan blackberry are present on the private residential property to the north of the channel where additional buffer mitigation plantings are proposed beyond the required berm revegetation. c. List threatened and endangered species known to be on or near the site. Several salmonid species have been documented by the Washington Department of Fish and Wildlife (WDFW) in the Madsen Creek low flow channel including summer/fall Chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), winter steelhead (O. mykiss), sockeye salmon (O. nerka), and resident coastal cutthroat trout (O. clarkii). However, the ability of these fish to swim upstream from the Cedar River into the project area is questionable given the lack of a defined Madsen Creek channel north of Ron Regis Park. Fish use is not documented by WDFW or WDNR within the high flow bypass channel. d. Proposed landscaping, use of native plants, or other measures to preserve or enhance vegetation on the site, if any: Impacted areas will be restored in-kind and, or enhanced, with native plant species at a 1:1 replacement ratio at Sites 1, 2, and 3. Vegetation in the portion of the Site 4 project area within the City of Renton will be restored with a 1:1 replacement ratio. Disturbances to Site 4, within King County’s regulated riparian buffer areas, will be restored and additional enhancement areas will be planted with native plants to meet the County’s critical areas buffer mitigation compensation ratio of 3:1. e. List all noxious weeds and invasive species known to be on or near the site. Reed canarygrass (Phalaris arundinacea) Himalayan blackberry (Rubus armenicus) Bittersweet nightshade (Solanum dulcamara) Common tansy (Taraxacum vulgare) Tansy ragwort (Jacobaea vulgaris) 5. Animals a. List any birds and other animals which have been observed on or near the site or are known to be on or near the site. Examples include: birds: hawk, heron, eagle, songbirds, other. mammals: deer, bear, elk, beaver, other. fish: bass, salmon, trout, herring, shellfish, other. Common songbirds are likely to inhabit the project area. Waterfowl and herons may occasionally make use of Madsen Creek and the sediment basin that the creek flows through at the upstream end of the project area. According to WDFW Priority Habitat and SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 17 of 28 Species (PHS) data, two biodiversity areas and corridors (defined as areas of habitat relatively important to various species of native fish and wildlife) are located in the project vicinity: one is within the southern portion of the project area, and the second is near the project area on the north side of the Cedar River. According to the eBird website, 65 species of birds have been observed in Ron Regis Park (eBird 2020). Common observed species include cedar waxwing (Bombycilla cedrorum), violet-green swallow (Tachycineta thalassina), barn swallow (Hirundo rustica), and European starlings (Sturnus vulgaris). Several salmonid species have historically used the Madsen Creek low flow channel, but salmonid use of the high flow bypass channel has not been documented by WDFW. Sockeye salmon (Onorhynchus nerka), kokanee salmon (O. nerka), resident coastal cutthroat (O. clarki clarki), and the threatened and endangered species listed below are documented in Madsen Creek and/or the Cedar River. b. List any threatened and endangered species known to be on or near the site. The following species are documented in the Cedar River and Madsen Creek: Puget Sound Chinook salmon (Oncorhynchus tshawytscha)—Threatened Puget Sound coho salmon (O. kisutch)—Species of Concern Winter Puget Sound steelhead (O. mykiss)—Threatened Bull trout (Salvelinus confluentus)—Threatened c. Is the site part of a migration route? If so, explain. The project site lies within the Pacific Flyway, one of four major north-south migration routes in the Americas for migratory birds. Washington State is part of the Pacific Flyway. Puget Sound serves as a migratory route for anadromous fish to migrate from their natal streams to the Pacific Ocean and back. Specifically, the project site is not identified as being part of a locally known migration route. d. Proposed measures to preserve or enhance wildlife, if any: Removing nonnative vegetation from all project sites and replacing with more appropriate native riparian vegetation species will provide a net benefit to wildlife species. Planting the constructed flood control berms with shrub species will provide a functional lift to existing riparian conditions currently comprised of nonnative herbaceous vegetation and, or grasses. e. List any invasive animal species known to be on or near the site. None are known. 6. Energy and Natural Resources a. What kinds of energy (electric, natural gas, oil, wood stove, solar) will be used to meet the completed project's energy needs? Describe whether it will be used for heating, manufacturing, etc. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 18 of 28 Once the project is complete, no energy inputs will be needed to operate the flood control improvements. Annual or semi-annual maintenance will require petroleum use to operate vehicles. Inspections by City staff may or may not utilize electric vehicles. b. Would your project affect the potential use of solar energy by adjacent properties? If so, generally describe. No. c. What kinds of energy conservation features are included in the plans of this proposal? List other proposed measures to reduce or control energy impacts, if any: None proposed. 7. Environmental Health a. Are there any environmental health hazards, including exposure to toxic chemicals, risk of fire and explosion, spill, or hazardous waste, that could occur as a result of this proposal? If so, describe. Construction activities will require the use of hazardous materials on site, including gasoline, diesel, motor oil, transmission fluid, hydraulic oil, radiator coolant, brake fluid, and metals used in tires. Accidental leaks and spills of hazardous materials could occur where construction equipment is parked, used, fueled, or maintained. 1. Describe any known or possible contamination at the site from present or past uses. None known. 2. Describe existing hazardous chemicals/conditions that might affect project development and design. This includes underground hazardous liquid and gas transmission pipelines located within the project area and in the vicinity. None. 3. Describe any toxic or hazardous chemicals that might be stored, used, or produced during the project's development or construction, or at any time during the operating life of the project. Construction activities will require the use of hazardous materials on site, including gasoline, diesel, motor oil, transmission fluid, hydraulic oil, radiator coolant, brake fluid, and metals used in tires. Accidental leaks and spills of hazardous materials could occur where construction equipment is parked, used, fueled, or maintained. 4. Describe special emergency services that might be required. As with any construction activity, there is a chance that emergency services may need to respond to a workplace accident or injury or an inadvertent spill or release of hazardous material. All work will be conducted in accordance with a site-specific health and safety plan required in the construction contract specifications. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 19 of 28 5. Proposed measures to reduce or control environmental health hazards, if any: All construction activities will be performed in compliance with Washington Industrial Safety and Health Act (WISHA) requirements. The City’s construction contractor will be required to provide a health and safety plan for approval before beginning work. Prior to beginning work, the contractor will also be required to prepare and implement a spill prevention, control, and countermeasures (SPCC) plan to avoid and mitigate impacts on soil, surface water, and groundwater in the event of a spill of hazardous substances during construction. The SPCC plan will address spill prevention and containment; spill response procedures, equipment, and reporting requirements; and the chain of responsibility. b. Noise 1. What types of noise exist in the area which may affect your project (for example: traffic, equipment, operation, other)? Noise from traffic along SR 169 currently contributes to the surrounding area, 24 hours a day, but is loudest during peak commuter hours on weekdays. 2. What types and levels of noise would be created by or associated with the project on a short-term or a long-term basis (for example: traffic, construction, operation, other)? Indicate what hours noise would come from the site. No new long-term sources of noise will be generated in association with the project. During the short-term construction phase of the project, noise from equipment operation, such as trucks, excavators, etc., will generated during daylight hours, coincident with times of day when traffic noise is prevalent along SR 169. The construction work is anticipated to occur only on weekdays during normal City of Renton daylight construction hours. 3. Proposed measures to reduce or control noise impacts, if any: None proposed, beyond following the requirements of the City’s and King County’s noise ordinances, as applicable. 8. Land and Shoreline Use a. What is the current use of the site and adjacent properties? Will the proposal affect current land uses on nearby or adjacent properties? If so, describe. All four sites where project construction will occur are currently functioning as buffers to critical areas. The sediment basin at Site 1 and the high flow bypass channel (Site 2) are operated by the City of Renton as a flood control facility associated with Madsen Creek. Site 3 fronts the Wonderland Estates housing development main office and parking area and extends along the creek bank in City right-of-way north of a single-family residential property to the east. All of Site 3 currently contains landscaped vegetation. The south side of Site 4 is adjacent to the Cedar River Trail. Most of this site is a non-landscaped vegetated area owned by a private residence to the north. The existing uses of the SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 20 of 28 residential properties, the field owned by the church east of the high flow bypass channel, the Cedar River Trail, and roads directly adjacent to the project work sites will not change in association with the project; however, creek-induced flooding in the project area will be reduced, thus enhancing uses of existing lands and roads in the project area. b. Has the project site been used as working farmlands or working forest lands? If so, describe. How much agricultural or forest land of long-term commercial significance will be converted to other uses as a result of the proposal, if any? If resource lands have not been designated, how many acres in farmland or forest land tax status will be converted to nonfarm or nonforest use? Not Applicable 1. Will the proposal affect or be affected by surrounding working farm or forest land normal business operations, such as oversize equipment access, the application of pesticides, tilling, and harvesting? If so, how: Not Applicable c. Describe any structures on the site. The sediment basin outlet to the high flow bypass channel is a concrete box culvert. Construction at Site 1 will occur on the gravel access driveway atop that culvert, and the new armored spillway will extend down into the bypass channel surrounding the culvert outlet. A sewer manhole cover will need to be raised flush with the elevated ground at the northwest side of the spillway. At Site 2 there is an existing fence on the east side of the high flow bypass channel and a gravel maintenance access driveway that parallels the west side of the channel. At Site 3 there is concrete forming the banks of the stream channel near the entrance to the culvert beneath SR 169, a utility pole and a guy wire that anchors it, overhead power and telephone lines, a private streetlight and sign, chain link fence that borders the lawn of the residence at the east end of the site, concrete curbing, and stormwater infrastructure associated with the Wonderland Estates development. There is a utility pole at Site 4 and an existing fence bordering the east side of the 149th Avenue Southeast right-of-way. Another fence in dilapidated condition extends from the east into the Site 4 work area; this fence will be replaced in kind if needed per coordination with the landowner. A King County wastewater sewer main is adjacent to the sediment basin, runs the length of the maintenance access driveway between the sediment basin and SR 169, crosses under SR 169 and continues northwest under the Site 4 location. d. Will any structures be demolished? If so, what? An existing, dilapidated chain link fence at Site 4 will be removed to enable site clearing for berm construction. No other structures will be demolished as part of the project. e. What is the current zoning classification of the site? The project area spans several zoning classifications in the City of Renton; Residential-14 (Sites 1 and 2), Residential Manufactured Home (Site 3), and Resource Conservation (Site 4). A portion of Site 4 is zoned as Urban Reserved (one dwelling unit per 5 acres) by King County. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 21 of 28 f. What is the current comprehensive plan designation of the site? Under the City of Renton Comprehensive Plan, Sites 1, 2, and 3 are located in a High Density Residential designated area. Site 4 is designated as Low Density Residential by the City of Renton and Greenbelt/Urban Separator by King County. g. If applicable, what is the current shoreline master program designation of the site? Site 4 is designated as Urban Conservancy by the City of Renton, and Residential by King County. Although portions of Sites 2 and 3 are within the 100-year floodplain of the Cedar River they are not subject to the City’s shoreline regulations as they are outside the shoreline buffer. h. Has any part of the site been classified as a critical area by the city or county? If so, specify. Construction work at all four sites will occur within stream (or aquatic area) buffers as classified by the City and County. Site 2 will require work within the high flow bypass channel, which is classified by the City of Renton as a Type-F stream. King County maintains the lower half of the high flow bypass channel, downstream of SR 169, to the Cedar River and classifies the high flow bypass channel as Type N in that area; as does the Washington State DNR and WDFW for the entire length of the high flow bypass channel. Project work at Sites 3 and 4 will also occur within wetland buffers. There will be no work within wetland boundaries or directly within the Madsen Creek low flow channel. i. Approximately how many people would reside or work in the completed project? None. j. Approximately how many people would the completed project displace? None. k. Proposed measures to avoid or reduce displacement impacts, if any: Not applicable. l. Proposed measures to ensure the proposal is compatible with existing and projected land uses and plans, if any: Plantings at Sites 2, 3, and 4 will restore attractive (and native) vegetation that is compatible with the interests of the affected property owners. m. Proposed measures to reduce or control impacts to agricultural and forest lands of long-term commercial significance, if any: Not applicable. 9. Housing a. Approximately how many units would be provided, if any? Indicate whether high, middle, or low-income housing. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 22 of 28 Not Applicable b. Approximately how many units, if any, would be eliminated? Indicate whether high, middle, or low-income housing. Not Applicable. c. Proposed measures to reduce or control housing impacts, if any: None, Not Applicable. 10. Aesthetics a. What is the tallest height of any proposed structure(s), not including antennas; what is the principal exterior building material(s) proposed? The proposed sediment basin spillway and flood control berms are designed to be 1 foot to 3 feet above existing grades, and thus will be subtly noticeable features. The proposed concrete floodwall at the east end of Site 3 will be approximately 15 inches above ground level adjacent to the south creek bank, and will be on the north side of an existing arborvitae hedge, which will be retained. b. What views in the immediate vicinity would be altered or obstructed? No views will be obstructed as a component of the project work. Six trees on the east side of the high flow bypass channel will be removed for Site 2 construction. These trees are spread apart and do not form a distinct stand when viewed from the east or west. The riparian plantings along the east side of the high flow bypass channel at Site 2, in an area largely devoid of existing trees or shrubs, will enhance views to the east from Wonderland Estates and the private residence at 14937 Maple Valley Hwy; as well as toward the western property boundary of New Life Church where the work at Site 2 is within an existing easement. Construction of the berm at Site 3 will require clearing of landscaped vegetation fronting Wonderland Estates. Construction of the berm at Site 4 will require clearing vegetation on the south edge of a residential property. Berm design at these two sites is being done in coordination with the property owners to address their aesthetic concerns. Mitigation plantings may help to improve current views by removing invasive vegetation and creating an attractive visual buffer between residences and the highway. c. Proposed measures to reduce or control aesthetic impacts, if any: None. 11. Light and Glare a. What type of light or glare will the proposal produce? What time of day would it mainly occur? None. b. Could light or glare from the finished project be a safety hazard or interfere with views? SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 23 of 28 Not Applicable. c. What existing off-site sources of light or glare may affect your proposal? Vehicles, streetlights from SR 169, and lights from residences are the only existing sources of light from off-site sources. d. Proposed measures to reduce or control light and glare impacts, if any: None; Not Applicable 12. Recreation a. What designated and informal recreational opportunities are in the immediate vicinity? Ron Regis Park is a 45-acre park featuring areas used for baseball, soccer, and basketball, and is located immediately northwest of the project area. Farther to the west is the Maplewood Golf Course. The Cedar River Trail parallels the north side of SR 169 and is at the south edge of Site 4. Farther to the east along the highway is Cedar River Park. A recreational field with a playground and trail owned by New Life Church is present to the east of the Madsen Creek high flow bypass channel at Site 2. b. Would the proposed project displace any existing recreational uses? If so, describe. No permanent recreational use displacement will occur. Construction at Site 4 may require brief interruption of Cedar River Trail traffic in the immediate area if construction materials are delivered via the trail (to be determined during project permitting). Such intermittent disruptions would be on the order of several minutes within a 1 to 2-week period of time, on weekdays. c. Proposed measures to reduce or control impacts on recreation, including recreation opportunities to be provided by the project or applicant, if any: If construction access to Site 4 via the Cedar River Trail is approved in project permits, the City’s construction contractor will be required to prepare and implement a trail traffic control plan, including measures to safely minimize trail use disruptions. 13. Historic and Cultural Preservation a. Are there any buildings, structures, or sites, located on or near the site that are over 45 years old listed in or eligible for listing in national, state, or local preservation registers? If so, specifically describe. None. b. Are there any landmarks, features, or other evidence of Indian or historic use or occupation? This may include human burials or old cemeteries. Are there any material evidence, artifacts, or areas of cultural importance on or near the site? Please list any professional studies conducted at the site to identify such resources. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 24 of 28 None. c. Describe the methods used to assess the potential impacts to cultural and historic resources on or near the project site. Examples include consultation with tribes and the department of archeology and historic preservation, archaeological surveys, historic maps, GIS data, etc. All the project sites have been previously disturbed in association with current land uses and corresponding construction activity. Neither the high flow bypass channel nor the low flow channel is in the historical, natural alignment of Madsen Creek. Where subsurface excavation is proposed for embedding spillway rock (Site 1) and flood control berm construction (Sites 2, 3 and 4), previous construction has occurred; and thus, archaeological evidence is not likely to be present. Sites 3 and 4 are adjacent to residential developments, the highway, and a major public trail. d. Proposed measures to avoid, minimize, or compensate for loss, changes to, and disturbance to resources. Please include plans for the above and any permits that may be required. If ground disturbing or other activities result in the inadvertent discovery of archaeological deposits, work would be halted in the immediate area and contact made with the State Department of Archaeology and Historic Preservation in Olympia. Work would be halted until such time as further investigation and appropriate consultation is concluded. In the unlikely event of the inadvertent discovery of human remains, work would be immediately halted in the area, the discovery covered and secured against further disturbance, and contact made with law enforcement personnel, in accordance with the City of Renton’s and/or King County’s Inadvertent Discovery Plan. Compliance with all applicable laws pertaining to archaeological resources would be required. 14. Transportation a. Identify public streets and highways serving the site or affected geographic area and describe proposed access to the existing street system. Show on site plans, if any. The project is located near SR 169 (Maple Valley Road). Site 4 is located adjacent to 149th Avenue Southeast, a residential street that also serves as access to the public parking lot at Ron Regis Park. Sites 1 and 2 will be accessed via a gated maintenance access driveway from SR 169 operated by the City of Renton. Site 3 will be accessed via Pine Drive, a private collector road in the Wonderland Estates development. b. Is the site or affected geographic area currently served by public transit? If so, generally describe. If not, what is the approximate distance to the nearest transit stop? The site is currently served by King County Metro bus service. The nearest bus stop is located at the intersection of Maple Valley Road and 149th Avenue Southeast, approximately 100 feet west of Site 3. c. How many additional parking spaces would the completed project or nonproject proposal have? How many would the project or proposal eliminate? None; Not Applicable. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 25 of 28 d. Will the proposal require any new or improvements to existing roads, streets, pedestrian, bicycle, or state transportation facilities, not including driveways? If so, generally describe (indicate whether public or private). The proposal includes improvements to the maintenance access driveway at Site 2; however, this driveway is gated and not accessible to the public. The proposal may require removal of existing concrete curbing at the north edge of the Wonderland Estates office parking area along the south side of Site 3 during construction. If that is necessary, in-kind curb replacement will be part of the construction work. No other roads or trails will be modified for project construction. e. Will the project or proposal use (or occur in the immediate vicinity of) water, rail, or air transportation? If so, generally describe. No; Not Applicable. f. How many vehicular trips per day would be generated by the completed project or proposal? If known, indicate when peak volumes would occur and what percentage of the volume would be trucks (such as commercial and non-passenger vehicles). What data or transportation models were used to make these estimates? Maintenance of the existing sediment basin requires several vehicle trips per year, mainly associated with trucks that haul removed sediment offsite during the summer months. That vehicular use will continue to the same extent as it would occur without construction of the proposed project. Monitoring of mitigation plantings will require an additional 1–3 vehicle trips per year by a biologist and vegetation maintenance crews for a period of 5 years after construction. g. Will the proposal interfere with, affect, or be affected by the movement of agricultural and forest products on roads or streets in the area? If so, generally describe. No; Not Applicable. h. Proposed measures to reduce or control transportation impacts, if any: None; Not Applicable. 15. Public Services a. Would the project result in an increased need for public services (for example: fire protection, police protection, public transit, health care, schools, other)? If so, generally describe. Not Applicable b. Proposed measures to reduce or control direct impacts on public services, if any. None; Not Applicable SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 26 of 28 16. Utilities a. Circle utilities currently available at the site: electricity, natural gas, water, refuse service, telephone, sanitary sewer, septic system, other ___________ Existing utilities (electricity, telephone, water, gas, sewer, storm drainage) are present within and near the proposed construction sites. b. Describe the utilities that are proposed for the project, the utility providing the service, and the general construction activities on the site or in the immediate vicinity which might be needed. Impacts or conflicts with utilities are not anticipated during construction. There is a wastewater sewer manhole amid the spillway construction area at Site 1. The manhole lid will be raised to be flush with the finished ground surface as part of construction. Similarly, there is a sewer manhole at Site 3 that will have its lid raised to be flush with the finished ground surface. There is a utility pole near the new berm at Site 3 and the connecting overhead communications and power lines are above the south edge of the Madsen Creek low flow channel where work will commence. Coordination with Puget Sound Energy will occur as part of final design and construction to determine whether any action is needed. If needed, the City will consult with those private or public utilities in advance of any subsurface excavation work. SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 27 of 28 C. Signature The above answers are true and complete to the best of my knowledge. I understand that the lead agency is relying on them to make its decision. Signature: ___________________________________________________________________ Name of signee _______________________________________________________________ Position and Agency/Organization ________________________________________________ Date Submitted: ____________ D. Supplemental sheet for nonproject actions (IT IS NOT NECESSARY to use this sheet for project actions) Because these questions are very general, it may be helpful to read them in conjunction with the list of the elements of the environment. When answering these questions, be aware of the extent the proposal, or the types of activities likely to result from the proposal, would affect the item at a greater intensity or at a faster rate than if the proposal were not implemented. Respond briefly and in general terms. 1. How would the proposal be likely to increase discharge to water; emissions to air; production, storage, or release of toxic or hazardous substances; or production of noise? Proposed measures to avoid or reduce such increases are: 2. How would the proposal be likely to affect plants, animals, fish, or marine life? Proposed measures to protect or conserve plants, animals, fish, or marine life are: 3. How would the proposal be likely to deplete energy or natural resources? Proposed measures to protect or conserve energy and natural resources are: 4. How would the proposal be likely to use or affect environmentally sensitive areas or areas designated (or eligible or under study) for governmental protection; such as parks, wilderness, wild and scenic rivers, threatened or endangered species habitat, historic or cultural sites, wetlands, floodplains, or prime farmlands? Proposed measures to protect such resources or to avoid or reduce impacts are: 5. How would the proposal be likely to affect land and shoreline use, including whether it would allow or encourage land or shoreline uses incompatible with existing plans? Proposed measures to avoid or reduce shoreline and land use impacts are: Amanda Pierce City of Renton Surface Water Utility Engineer/Project Manager 04.20.2021 SEPA Environmental checklist (WAC 197-11-960) March 2021 Page 28 of 28 6. How would the proposal be likely to increase demands on transportation or public services and utilities? Proposed measures to reduce or respond to such demand(s) are: 7. Identify, if possible, whether the proposal may conflict with local, state, or federal laws or requirements for the protection of the environment.