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October 29, 2019 City of Redmond Planning and Community Development 15670 NE 85th St. PO Box 97010 Redmond, WA 98073-9710 RE: GARBARINO PROPERTY PREP 90% – PROJECT NARRATIVE Dear Technical Committee, The Garbarino property is a 2.60 acre residential project located at 10030 and 10042 136th Avenue NE, Redmond, Washington within the Willows/Rose Hill neighborhood. The proposed development is residential in nature and is within the current RIN zoning for the property. The proposed development is summarized by the following characteristics and narrative: Property Address: 10030 and 10042 136th Ave NE Property Zoning: RIN (5DU/Acre) Property Area: 2.60 AC Proposed Residential Units: 14 Proposed Residential density: 5.38 DU/Acre Proposed Streets Standard: Rustic Roads (per RZC Appendix 2) The existing residences on site will be removed as will all outbuildings. Tree retention will take place on site as outlined in the report by American Forest Management, Inc. Existing Site Conditions The rectangular 2.60 acre site is bounded to the north and south by single family properties also zoned Residential Innovative (RIN). To the east are single family properties zoned R1 while 136th Ave NE runs along the western property line. The development parcels maintain approximately 147 lineal feet of frontage along 136th Ave NE. The property generally slopes downward from the west to the east. There are no sensitive areas present on the site. The site contains many existing trees. Currently two homes exist on the property. Proposal The proposal is for the subdivision of the property into 14 single family residential units in accordance with the RIN zoning designation. All units are to be detached, except for the proposed duplex proposed for lots 7 and 8. Three units will be size limited, and one affordable unit is being proposed in accordance with City requirements. No lots will have direct access off of 136th Ave NE. The project will provide a single public ROW access/intersection with 136th Ave NE. Roadway improvements including along the frontage will be done in accordance with the Rustic Road Standards which include open ditches and sidewalks, with no vertical curb. Two open space tracts are proposed. Tract B will have a detention and water quality facility, and Tract A will be utilized as general open space/fire turnaround. ` ---PAGE BREAK--- Garbarino Property October 29, 2019 Page 2 of 3 The proposed development integrates the following dimensions, setbacks and road width criteria: Units: 5Du/Acre (Max); 5.38Du/Acre proposed due to bonus unit 21% Size Limited (3-lots) 7% Affordable (1-lot) Unit Size: Size limited ~ 1,900sf/Unit: Standard ~ 35% lot coverage Open Space: 20% Code Section: 21.08.070 RIN Average Lot Size: 4000sf min.; 5034sf proposed Lot Circle: 35ft Lot Frontage: 20ft Setbacks: Front: 15ft Side: 5/10ft Rear: 10ft Lot Coverage (struct.): 35% Max Imp. Cover: 65% Max Struct. Ht: 25ft Drainage The existing Garbarino site is within watershed Basin 059 (tributary to Sammamish River). The property drains from west to east. Runoff from the property separates at the easterly end of the property, and crosses the private road (138th Ave NE) in culverts at both the north and south. The discharge from these culverts are considered within the same threshold discharge area, combining at or near the 1/4–mile threshold prior to Willows Road. The drainage in the project frontage drains south within a roadside ditch along the east ROW of 136th Ave NE. to the northerly roadside ditch within the NE 100th St. ROW. Frontage improvements will be made along the property frontage, including the standard Rustic Road section (with roadside swale) and developed condition flow within the frontage will continue to surface flow south to NE 100th St. Site Soils are classified as “Alderwood” by the NRCS, which is consistent with a dense glacial till soil of low infiltration potential. These classifications are consistent with the results of the geotechnical investigation for both the Benjamin and Hill properties, and a Geotechnical investigation for the proposed Garbarino development is forthcoming. Alderwood soils are identified by the SCS as Hydraulic Soil group Infiltration is not possible based on geotechnical evaluation. Wet Utilities: Water and sewer utilities are within the City of Redmond service boundaries. Water: Water is provided to this area by City of Redmond. A 8” DI main, constructed in 2004, is within 136th Ave NE. The water main will be extended into the site in order to provide water meters and fire protection (Fire Hydrant) to the proposed homes. Water will not connect ---PAGE BREAK--- Garbarino Property October 29, 2019 Page 3 of 3 through the property to either the Benjamin Estates Plat or the water line to the east, per previous conversation/meetings with Jim Streit. Sewer: Currently residences in this area are on septic sewer. Sewer service is proposed to be extended from NE 100th St, east of the proposed Garparino plat, along 138th Ave NE (Private Drive where a public easement has been negotiated with property owners). Garbarino sewer will connect to this proposed sewer extension from the east side of the property. Proposed Development Proposed/Developed Drainage Runoff in the developed condition will continue to flow west to east and will be collected by a series of roadside swales, culverts and catch basins, and conveyed to a detention and water quality vault on the far eastern portion of the site. The vault will employ wet-storage to provide Basic stormwater quality treatment prior to release. The vault will release mitigated flows to the east across the property line, and through the offsite proposed public drainage easement along the private drive, to connect with the 24” storm line installed down the bluff connecting to the public storm system in Willows Commerce Park. Fire: A fire turnaround is included between lots 4 and 5, and the proposed ROW length is less than 600ft. Thank you for the time and effort you have dedicated to making sure this project is a success. We look forward to working with you, and appreciate your review, input and assistance. Sincerely, LDC, Inc. Jason Tacchini, PE Project Manager LDC, Inc.