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HomeMy WebLinkAboutEx_14_Advisory_NotesDEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT Page 1 of 5 LUA24-000299 ADVISORY NOTES TO APPLICANT The following notes are supplemental information provided in conjunction with the administrative land use action. Because these notes are provided as information only, they are not subject to the appeal process for the land use action. Planning: (Contact: Alex Morganroth, 425-430-7219, amorganroth@rentonwa.gov) 1. RMC section 4-4-030.C.2 limits haul hours between 8:30 am to 3:30 pm, Monday through Friday unless otherwise approved by the Development Services Division. 2. Commercial, multi-family, new single family and other nonresidential construction activities shall be restricted to the hours between seven o’clock (7:00) a.m. and eight o’clock (8:00) p.m., Monday through Friday. Work on Saturdays shall be restricted to the hours between nine o’clock (9:00) a.m. and eight o’clock (8:00) p.m. No work shall be permitted on Sundays. 3. Within thirty (30) days of completion of grading work, the applicant shall hydroseed or plant an appropriate ground cover over any portion of the site that is graded or cleared of vegetation and where no further construction work will occur within ninety (90) days. Alternative measures such as mulch, sodding, or plastic covering as specified in the current King County Surface Water Management Design Manual as adopted by the City of Renton may be proposed between the dates of November 1st and March 31st of each year. The Development Services Division’s approval of this work is required prior to final inspection and approval of the permit. 4. A National Permit Discharge Elimination System (NPDES) permit is required when more than one acre is being cleared. 5. The applicant may not fill, excavate, stack or store any equipment, dispose of any materials, supplies or fluids, operate any equipment, install impervious surfaces, or compact the earth in any way within the area defined by the drip line of any tree to be retained. 6. The applicant shall erect and maintain six foot (6') high chain link temporary construction fencing around the drip lines of all retained trees, or along the perimeter of a stand of retained trees. Placards shall be placed on fencing every fifty feet (50') indicating the words, “NO TRESPASSING – Protected Trees” or on each side of the fencing if less than fifty feet (50'). Site access to individually protected trees or groups of trees shall be fenced and signed. Individual trees shall be fenced on four (4) sides. In addition, the applicant shall provide supervision whenever equipment or trucks are moving near trees. 7. This permit is shall comply with the Bald and Golden Eagle Protection Act. The permitted is responsible for adhering to the U.S. Fish and Wildlife Service National Bald Eagle Management Guidelines (2007) and /or your U.S. Fish and Wildlife Service permit. Development Engineering: (Contact: Yong Qi, 425-430-7439, yqi@rentonwa.gov) 1. See Attached Development Engineering Memo dated July 24, 2024 Docusign Envelope ID: E0F8843B-A22A-4BE7-8E8C-B885793CB9BA ADVISORY NOTES TO APPLICANT Page 2 of 5 LUA24-000218 DEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT M E M O R A N D U M DATE: July 24, 2024 TO: Alex Morganroth, Principal Planner FROM: Yong Qi, Development Engineer SUBJECT: Taxiway A Rehabilitation 616 W Perimeter Rd LUA24-000208 I have reviewed the application for the Taxiway A Rehabilitation project located at 616 W Perimeter Rd, parcel No: 0723059007, and have the following comments: EXISTING CONDITIONS: WATER: The proposed project is within the City of Renton’s water service area and in the Kennydale 308-hydraulic pressure zone. Below is a summary of the existing water system in the project vicinity: 1. There is an existing 16-inch City water main that bisects the project area and runway just north of 622 W Perimeter Road building (see City water project plan no. W-0799). The maximum capacity of the 16-inch water main is 4,500 gallons per minute (gpm). The static water pressure is approximately 119 psi at a ground elevation of 25 feet. 2. The proposed project area is serviced from an existing privately-owned 12-inch-high pressure water main that provides the required fire protection for Taxiway A and the Runway. SEWER: There is an existing a public 8” sewer main that service the buildings on the south portion of W perimeter Road (Reference COR Project File(s) S-1688). An existing 6-inch sewer main maintained by the Airport that services the buildings on the north portion of W perimeter Road. Currently there are no sewer mains that provide service to the project area. There is an existing 24” King County sewer main in a 40” casing that bisects the project area and runway north of 860 W Perimeter Road building. STORM DRAINAGE: The stormwater runoff from the airport is collected by a series of catch basins/manholes, and enter the Black River culvert under the airport's Perimeter Road to the west. The Black River Culvert is a large box culvert that flows from the south to north and discharges stormwater into Lake Washington. STREETS: This project fronts W Perimeter Road along the west property line(s) and E Perimeter Road along the east property line(s). Both roadways are private roads. WATER COMMENTS: 1. Water service is provided by City of Renton in the Kennydale 308-hydraulic pressure zone. Docusign Envelope ID: E0F8843B-A22A-4BE7-8E8C-B885793CB9BA ADVISORY NOTES TO APPLICANT Page 3 of 5 LUA24-000218 2. There is an existing 12-inch City water main along W perimeter Rd (Record Dwg: W-355002). The maximum capacity of the 12-inch water main is 2,800 gallons per minute (gpm). There is an existing 16-inch City water main that bisects the project area and runway north of 622 W Perimeter Road building (Record Dwg: W- 079903). The maximum capacity of the 16-inch water main is 4,500 gallons per minute (gpm). The static water pressure is approximately 119 psi at a ground elevation of 25 feet. 3. The existing water mains within Renton Municipal airport and along the existing taxiways and aprons are owned by the Airport with water supply from the Boeing Plant privately-owned water system. The Water Utility does not have as-built records of the water mains within the airport because they are not part of the City utility- owned water system. We recommend that airport staff verify the location of all existing valves and to exercise the valves to make sure that water supply can be shut off for the proposed capping and abandonment of the water mains as shown on the submitted 95% civil plans. 4. All backfill materials for the 2 new hydrant-laterals connecting to the city’s water system along W Perimeter Road shall be clean import materials. a. The preliminary utility plan depicts demolition and removal of a series of existing privately-owned high pressure fire waterline and associated appurtenances. Applicant shall obtain approval from the owner of the high-pressure water main prior to civil construction permit issuance. 5. Installation of off-site and on-site fire hydrants. The location and number of fire hydrants will be determined by the RRFA based on the final fire flow demand and final site plan. a. The preliminary utility plan depicts demolition and removal of a series of existing fire hydrants [i.e., one (1) above ground and seven (7) below grade], and proposes two new fire hydrants per COR Std Plan 310.1 with protection bollards. The two new fire hydrants will be connected to City of Renton public water mains. The location and number of fire hydrants will be reviewed and approved by the RRFA. b. Installation of a “Storz” adapter on the existing hydrants will be required if not already equipped with one. 6. Civil plans for the water main improvements must be prepared by a Professional Engineer registered in the State of Washington. Please refer to City of Renton General Design and Construction Standards for water main extensions as shown in Appendix K of the City’s 2021 Water System Plan. Adequate horizontal and vertical separations between the new water main and other utilities (storm sewer pipes and vaults, sanitary sewer, power, gas, electrical) shall be provided for the operation and maintenance of the water main. Retaining walls, rockeries or similar structural cannot be installed over the water main unless the water main is installed inside a steel casing. 7. All applicable COR standard plans shall be included in the final civil construction plans. 8. No SDC fees will be collected on City-owned properties per RMC 4-1-180.B.2.b. SEWER COMMENTS: 1. There is an existing 24” King County sewer main in a 40” casing that bisects the project area and runway north of 860 W Perimeter Road building. a. The existing KC 24’’ sewer main shall be protected during construction. b. The applicant should coordinate with KC if any additional requirements are warranted. 2. The project currently does not propose a connection to the City of Renton system. If this changes, additional requirements will be warranted. 3. Any dewatering activity that is proposed to be discharged to the sewer system, must receive approval from the City and King County Industrial Waste Program before discharge. STORM DRAINAGE COMMENTS: 1. Drainage plans and a drainage report complying with the adopted 2022 Renton Surface Water Design Manual is required. Refer to Figure 1.1.2.A – Flow Chart of the 2022 Renton Surface Water Design Manual (RSWDM) to determine what type of drainage review is required for this site. Based on the City’s flow control map, this site Docusign Envelope ID: E0F8843B-A22A-4BE7-8E8C-B885793CB9BA ADVISORY NOTES TO APPLICANT Page 4 of 5 LUA24-000218 falls within the Peak Rate Flow Control Standard area (matching existing site conditions). The site falls within West Lake Washington – Seattle Drainage basin. a. A preliminary stormwater technical information report (TIR) prepared by Kimley-Horn, Inc., dated May 13rd, 2024, was submitted by the Applicant with the Land Use Application, which was prepared following the 2022 RSWDM. b. Core Requirement #2, off-site analysis: A Level 1 downstream analysis was performed on Section 3.0 of the TIR. The stormwater runoff from the airport is collected by a series of catch basins/manholes, and enter the Black River culvert under the airport's Perimeter Road to the west. The Black River Culvert is a large box culvert that flows from the south to north and discharges stormwater into Lake Washington. Since no new impervious surfaces are added from the proposed project, there will be no predicted drainage or water quality issues will arise as part of the proposed project. c. Core Requirement #3, per the TIR, the site is within ¼ mile of Lake Washington. There is a discharge into the lake on the north side of the airport underneath a floating dock. Flow Control requirements are exempt for this project. Staff concurs with the assessment. 2. Conveyance, Core Requirement #4: All new conveyance systems constructed as part of the project must be sized to RSWDM standards for the total tributary area (onsite and offsite) that the storm systems serve. a. The preliminary TIR depicts the new pipe systems are simply a replacement of existing facilities in-kind, no analysis of the existing system has been conducted. Since no new impervious areas are added from the proposed project, and there are no existing drainage issues, staff concurs with the assessment where the new pipe matches the existing pipe alignment, diameter, and slope. However, where new pipe does not directly replace pipe of the same alignment, diameter, and slope, a backwater analysis (including tailwater condition of Lake Washington) is required. 3. Construction Stormwater Pollution Prevention, Core Requirement #5: a. A temporary ESC plan and CSWPP is submitted with the land use application, staff has reviewed the preliminary ESC plan and determined it is acceptable. 4. Water Quality, RSWDM Core Requirement #8: If the new plus replaced pollution generating impervious (PGIS) surface exceeds 5,000 SF, the applicant will be required to provide enhanced basic water quality treatment. a. The preliminary TIR indicates this project qualifies for the Surface Exemption for Transportation Redevelopment Projects per Section 1.2.8 of the 2022RSWDM as the total new impervious surface within the project limits is less than 50% of the existing impervious surface, less than 5,000 square feet of new PGIS will be added, and less than ¾ acre of new Pollution Generating Pervious Surface (PGPS) will be added, therefore new water quality facilities are not required. Staff has reviewed the analysis and determined it is acceptable. 5. Appropriate on-site BMPs satisfying Core Requirement #9 will be required to help mitigate the new runoff created by this development to the maximum extent feasible. On-site BMPs shall be evaluated as described in Section C.1.3 of the 2022 RSWDM. A preliminary drainage plan, including the application of on-site BMPs, shall be included with the land use application, as appliable to the project. The final drainage plan and drainage report must be submitted with the utility construction permit. a. The preliminary TIR depicts On-Site BMPs such as pervious pavement, rain gardens, and Low Impact Development features are not feasible on the airport within the Air Operations Area (AOA). The FAA has strict rules on the locations of wildlife attractive BMPs which are a danger to aircraft and the traveling public. Pervious pavement does not meet the loading criteria for airplanes and cannot be used on this project where aircraft is the design vehicle. Staff concurs with the assessment and determined it is acceptable. 6. A geotechnical report for the site is required and shall be submitted with the land use application. Information concerning the soils, geology, drainage patterns, vegetation present, water table and soil permeability, with recommendations of appropriate on-site BMP options with typical designs for the site from the geotechnical engineer, shall be submitted with the application. The geotechnical report should include an on-site infiltration test to clearly show if the site is suitable or unsuitable for infiltration. a. A draft geotechnical report prepared by HWA Geosciences Inc dated April 26, 2024 was submitted with the land use application. The report contains information on soil infiltration capacity, groundwater table location, and soil types. The report concludes that fill soils are encountered below the buried pavement Docusign Envelope ID: E0F8843B-A22A-4BE7-8E8C-B885793CB9BA ADVISORY NOTES TO APPLICANT Page 5 of 5 LUA24-000218 consists of gravel or sand with varying amounts of silt, and sandy silt, the average fill thickness below Taxiway A was approximately 5 feet. Groundwater was encountered at the depth varied from 4 feet to 9.5 feet below the existing surface. A pilot infiltration test was attempted, but no water was infiltrated during a 3-hour test, therefore infiltration is not feasible on the project site. b. The draft geotechnical report shall be finalized, stamped, and dated by a licensed Geotechnical engineer prior to the civil construction permit issuance. 7. The site falls within Zone 2 of the City’s Aquifer Protection Area (APA). Therefore, open facilities and open conveyance systems, if proposed, may require a liner in accordance with the design criteria in Sections 6.2.4 and 1.2.3.3 of the 2022 RSWDM. a. No storm open facilities or open conveyance systems are proposed on the submitted civil plans. 8. A Construction Stormwater Permit from Department of Ecology is required since clearing and grading of the site exceeds one acre. Applicant must obtain permit and provide proof prior to Civil Permit issuance. a. The Applicant must apply for this permit with the Department of Ecology. An active permit is required before issuance of the Civil Construction Permit. 9. The 2024 Surface water system development fee is $0.92 per square foot of new impervious surface, but no less than $2,300.00. This is payable prior to issuance of the construction permit and are not vested to the rates at land- use approval. This fee is subject to change based on the calendar year the construction permit is issued. a. No SDC fees will be collected on City-owned properties per RMC 4-1-180.B.2.b. TRANSPORTATION/STREET COMMENTS: 1. Since this project is interior to the property, no street frontage improvements or right of way dedication are required. 2. Paving and trench restoration shall comply with the City’s Trench Restoration and Overlay Requirements or Federal Aviation Administration (FAA) standards, whichever is greater. GENERAL COMMENTS: 1. The fees listed are for 2024. The fees that are current at the time of the respective permit issuance will be levied. Please see the City of Renton website for the current fee schedule. Docusign Envelope ID: E0F8843B-A22A-4BE7-8E8C-B885793CB9BA