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Home My WebLink AboutERC_Mitigation_Measures_and_Advisory_Notes_180316 ERC Mitigation Measures and Advisory Notes Page 1 of 5 DETERMINATION OF NON-SIGNIFICANCE – MITIGATED (DNS-M) MITIGATION MEASURES AND ADVISORY NOTES PROJECT NUMBER: LUA18-000115, ECF, CU-H APPLICANT: David Ketchum, Airsafe / PO Box 287 Greenbank, WA 98253 / (360) 678-0345 / David@airsafeheliports.com PROJECT NAME: Southport Office Helipad PROJECT DESCRIPTION: The applicant is requesting a Hearing Examiner Conditional Use Permit (CUP) and Environmental (SEPA) Review to construct a rooftop helipad near the south end of Tower 2 at the Southport Office Complex. The structure on which the helipad is proposed is part of a three-structure office complex that has been permitted separately and is currently under construction. Tower 2 is located in the Urban Center (UC) zoning district on a 245,086 square feet (5.63 acres) parcel at 1101 Lake Washington Blvd N. The 9-story Southport Office Building 2 has been designed to support a thickened concrete helipad slab measuring 30 ft x 30 ft (900 sf) in size. The helipad would be classified as “private-use” helipad for light-turbine helicopters, classified as H-1. The surrounding landmarks include Renton Municipal Airport to the west, I-405 Freeway to the east and Lake Washington approximately 650 feet to the north. The proposed helipad is expected to have minimal effect on adjacent properties. PROJECT LOCATION: 1101 Lake Washington Blvd N Renton, WA 98056 LEAD AGENCY: The City of Renton Department of Community & Economic Development Planning Division MITIGATION MEASURES: 1. The Southport Office Helipad operator shall limit engine and rotor-system running times to the minimum necessary for safe operations and consistency with helicopter and engine manufacturer recommendations. 2. The operator of the Southport Office Helipad shall employ Helicopter Association International’s (HAI) Fly Neighborly Program. 3. Helipad operating hours 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. Operating hours on Saturdays shall be restricted to the hours between nine o’clock (9:00) a.m. and six o’clock (6:00) p.m. No flights shall be permitted on Sundays. 4. The helipad shall be restricted to a maximum of twelve (12) landings and takeoff per week. 5. The helipad shall be restricted to light-turbine helicopters only, except for larger helicopters in case of an emergency. Nexus: RMC 4-9-070, Environmental Review Procedures and RMC Chapter 7, Noise Level Regulations. ERC Mitigation Measures and Advisory Notes Page 3 of 5 ADIVISORY NOTES: 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 actions. Planning: (Contact: Clark H. Close, 425-430-7289, cclose@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 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. This permit shall comply with the Bald and Golden Eag le 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: Ian Fitz-James, 425-430-7288, IFitz-James@rentonwa.gov) 1. See Attached Development Engineering Memo dated March 8, 2018. Fire Authority: (Contact: Corey Thomas, 425-430-7024, cthomas@rentonwa.gov) 1. Proposed helistop shall comply with Section 2007 of the International Fire Code, 2015 Edition. 2. Fuel spill control shall be provided. 3. Proper exit stair shall be provided. 4. Fire Standpipe shall be provided. 5. A type 80BC rated portable fire extinguisher shall be provided. Technical Services: (Contact: Amanda Askren, 425-430-7369, aaskren@rentonwa.gov) 1. Reviewed, no comment. Community Services: (Contact: Leslie Betlach, 425-430-6619, lbetlach@rentonwa.gov) 1. Reviewed, no comment. Police: (Contact: Cyndie Parks, 425-430-7521, cparks@rentonwa.gov) 1. Reviewed, no comment. Building: (Contact: Craig Burnell, 425-430-7290, cburnell@rentonwa.gov) 1. Reviewed, no comment. ERC Mitigation Measures and Advisory Notes Page 4 of 5 DEPARTMENT OF COMMUNITY & ECONOMIC DEVELOPMENT M E M O R A N D U M DATE: March 8, 2018 TO: Clark Close, Senior Planner FROM: Ian Fitz-James, Civil Engineer III SUBJECT: Utility and Transportation Comments for Southport Helipad LUA18-000115 I have reviewed the application for the Southport Helipad proposed for the roof of Tower 2 in the Southport Office Towers located at 1101 Lake Washington Boulevard N. and have the following comments: WATER COMMENTS 1. Any standpipe that is required to serve the helipad that is connected to the City’s water system must be protected by an approved backflow prevention assembly. SEWER COMMENTS 1. The proposal will not require any sanitary sewer improvements. STORM DRAINAGE COMMENTS 1. Based on the information provided in the application and further review of the 2017 Renton Surface Water Design Manual (RSWDM) and the 2014 Washington Department of Ecology Stormwater Management Manual for Western Washington (SWMMWW), the City does not consider the helipad to be pollution generating impervious surface (PGIS). No additional stormwater improvements will be required for the proposed helipad. The approved drainage plans and technical information report on file for the Southport Office Towers already accounts for the helipad surface as non-pollution generating impervious surface. a) The 2017 RSWDM defines “PGIS” as surfaces subject to vehicular use, industrial activities, or storage of erodible or leachable materials, wastes, or chemicals and that receive direct rainfall or the run-on or blow-in of rainfall. The 2017 RSWDM also defines “subject to vehicular use” as a surface regularly used by motor vehicles including but not limited to motorcycles, cars, trucks, buses, aircraft, tractors, and heavy equipment. The definition goes on to provide examples of surfaces subject to vehicular use and not subject to vehicular use. The following surfaces are considered regularly used by motor vehicles by the 2017 RSWDM: roads, un-vegetated road shoulders, bike lanes within the traveled ERC Mitigation Measures and Advisory Notes Page 5 of 5 lane of a roadway, driveways, parking lots, unrestricted access fire lanes, vehicular equipment storage yards, and airport taxiways and runways. The following surfaces are not considered regularly used by motor vehicles by the 2017 RSWDM: paved bicycle pathways separated from and not subject to drainage from roads for motor vehicles, fenced or restricted access fire lanes, and maintenance access roads with a recurring use of no more than one routine vehicle access per week. b) The 2014 SWMMWW defines vehicular use as the regular use of an impervious or pervious surface by motor vehicles. The 2014 SWMMWW goes on to provide examples of surfaces subject to vehicular use and not subject to vehicular use. The following surfaces are considered subject to regular vehicular use by the 2014 SWMMWW: roads, un-vegetated road shoulders, bike lanes within the traveled lane of a roadway, driveways, parking lots, unrestricted access fire lanes, vehicular equipment storage yards, and airport runways. The following are not considered subject to regular vehicular use by the 2014 SWMMWW: paved bicycle pathways separated from and not subject to drainage from roads for motor vehicles, restricted access fire lanes, and infrequently used maintenance access roads. The proposed helipad is similar in function to that of a restricted access maintenance road which is not considered PGIS by both the 2017 RSWDM and 2014 SWMMWW. The risk of leaking fluids is negligible. There is no pollution being emitting from brake pads since helicopters do not require runways to take off and land. TRANSPORTATION/STREET COMMENTS 1. The proposal will not generate any new traffic and will not require any improvements to the nearby public streets.