9307 18TH AVE W 2025-04-18 - Laserfiche WebLink

• Snohomish County PDS Map Portal: The PDS Map Portal depicts a non-fish bearing stream east of the property. Additionally, the same wetland complex as the NWI and PHS maps is shown. • WDFW SalmonScape: SalmonScape depicts the same stream as the PDS map portal. No fish presence is shown within this stream. • City of Everett Interactive Map: City of Everett depicts the stream to the east of the property as Swamp Creek, a Type F stream. 2.2 DETERMINATION METHODOLOGY The ordinary high water mark (OHWM) of streams is determined using the methodology described in the Washington Department of Ecology's publication, Determining the Ordinary High Water Mark for Shoreline Management Act Compliance in Washington State (Anderson, et al. 2016). Wetland boundaries in western Washington are determined using the routine methodology described in the 2010 Regional Supplement to the Corps of Engineers Wetland Delineation Manual.• Western Mountains, Valleys, and Coast Region (Version 2.0), (referred to as 2010 Regional Supplement). Under this method, the process for making a wetland determination is based on three sequential steps: 1) Examination of the site for hydrophytic vegetation (species presence and coverage); 2) If hydrophytic vegetation is found, then the presence of hydric soils is determined; 3) Determination of the presence of wetland hydrology in the area examined under the first two steps. The following criteria must be met in order to make a positive wetland determination: 2.2.1 Hydrophytic Vegetation Criteria The 2010 Regional Supplement defines hydrophytic vegetation as"the community of macrophytes that occurs in areas where inundation or soil saturation is either permanent or of sufficient frequency and duration to exert a controlling influence of the plant species present." Field indicators were used to determine whether the vegetation meets the definition for hydrophytic vegetation. 2.2.2 Soils Criteria and Mapped Description The National Technical Committee for Hydric Soils, as described in the 2010 Regional Supplement, defines hydric soils as "a soil that formed under conditions of saturation,flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part." Field indicators were used to determine whether a given soil meets the definition for hydric soils. The soils underlying the site are mapped by USDA-NRCS(Web Soil Survey)as Alderwood-Urban land complex, 2-8% slopes. Talley - 18th Ave W 3 Critical Area Study and Buffer Restoration Plan WRI#19238 November 6, 2019