4800 DOGWOOD DR 2022-02-28 - Laserfiche WebLink

• View Ridge Comm.Church Add. Minimum Requirement # 1: Stormwater Site Plan • Executive Summary The proposed project consists entirely of clearing/grading and removal of existing gravel for the construction of an addition to an existing church building with expansion and restriping of an existing paved parking area. Access to the site to be provided directly • from Dogwood Drive to the east of the site. Any new utilities to be provided by existing services within Dogwood Drive. Drainage management for new on-site runoff will be provided by roof drain dispersion • (dispersion trench located in southwestern portion of the site) and parking lot sheet flow type dispersion directly west of minor parking asphalt addition. Parking lot dispersion area to receive surface runoff from both the existing parking lot asphalt and new 7'-10' asphalt addition to western parking area. Vegetated dispersion flow path(30') sized to • disperse both existing and new asphalt parking area from the southern, central and western portions of the parking area. Disturbed pervious areas will be amended per BMP T5.13. Total new/replaced hardscape has been calculated at approximately 3,570 sf. and does not require water quality or flow control measures. The project is to be designed according to the 2014 Stormwater Management Manual for Western Washington • (SWMMWW). Refer to sheet 3 of 3 in the civil drawing set for additional drainage design features, MR#7 for full detail of pervious and hardscape areas associated with the development along with Geotech peer review letter for analysis of proposed dispersion BMP's. • Existing Conditions Summary The site consists of three parcels which contain an existing church, school, and parking lot. Existing vegetation resembles commercial lawn and landscaping. The site tends to • slope westerly toward an off-site stream at slopes ranging from 4%to 40%. From a Snohomish County Soil Survey done by the USDA NRCS the soils on-site consist of "Alderwood Urban Land Complex"type soils. According to a soil boring performed by Associated Earth Sciences, Inc. on-site soils resemble fine to medium sand. Refer to "Subsurface Exploration, Geologic Hazards, and Geotechnical Engineering Report"by • Associated Earth Sciences, Inc. dated August 29, 2016 for more detailed soil information. The surrounding parcels are developed with existing residences and driveways. Vegetation in the surrounding area generally consists of residential lawn with partial tree • cover. The Dogwood Drive right-of-way lies along the eastern boundary of the site. • WESTERN ENGINEERS,INC. 2 PROJECT:17-1619-A