2235 LAKE HEIGHTS DR 2020-12-23 - Laserfiche WebLink

2.0 Project Description The Bethany at Silver Lake project will include two building additions to the existing easternmost building, as well as a new 12-stall parking lot accessed off Lake Heights Drive. In addition to these improvements, stormwater, hardscape, and landscape improvements will also be a part of the proposed project. In this report,the northernmost building addition will be referred to as the North Building Addition, while the southernmost building addition will be referred to as the South Building Addition. The project site is located at 2235 Lake Heights Drive, Everett, Washington. The site is bordered on all sides by residential properties, and is accessed by a single entrance off Lake Heights Drive.The site consists of three Snohomish County tax parcels(28052900205100, -5000, and -4900),totaling approximately 8.62 acres in size. Project improvements will occur at various locations around the site and will disturb approximately 1.01 acres. 3.0 Existing Site Conditions The project area is approximately 1.01 acres in size and is located approximately 0.20 mile 1 southeast of Silver Lake, at the end of Lake Heights Drive. The site is accessed from the south by a single driveway entrance. There are currently 118 parking stalls throughout the site that serve two buildings.An existing detention pond is located at the northwest corner of the site that captures site runoff and discharges to Silver Lake. 4.0 Adjacent Areas and Drainage I The project site is bordered on all sides by single-family residences. The existing grades are such that offsite runoff should be considered minimal. There are two structures located in the right-of- way that capture runoff from the cul-de-sac and convey it onto the project site. From here, runoff is conveyed through the site's storm network and discharges into the detention pond. The project discharges runoff from the existing detention pond through a 12-inch diameter pipe. The pipe enters Lake Heights Drive SE, where it combines with the City of Everett system. From here,the stormwater is conveyed northwest, along Lake Heights Drive SE.The City system travels approximately 0.20 mile through a network of 12-inch diameter pipe and discharges into Silver Lake.The qualitative downstream analysis did not indicate any drainage issues with the existing system. 5.0 Critical Areas I There are no known critical areas on the site or in the immediate vicinity of the project. 6.0 Soils 1 Earth Solutions NW, LLC prepared a Geotechnical Engineering Study for the project site (dated October 18, 2018), which indicates that soils generally consist of dense to very dense glacial till. This type of soil typically carries little to no infiltration capacity and should be considered impervious. Groundwater was encountered at the time of the exploration at approximately 16 feet below ground surface at one of the boring locations. , 7.0 Potential Erosion Problems There are no known areas that would create potential erosion problems on the site or in the 1 immediate vicinity of the project. heConstructionBetay at Silver Lake r Pollution Prevention Plan The Bethany at Silver L 2 0121 2180406.10