2202 100TH ST SW 2023-02-07 - Laserfiche WebLink

Stephens Property Critical Areas Report and Mitigation Plan EXECUTIVE SUMMARY PROJECT NAME: Stephens Property (Airport 100) SITE LOCATION: The Stephens Property is an assemblage of three (3) parcels in the southeast quadrant of the 100th Street SW and 23rd Avenue W intersection in Everett, Washington. The Snohomish County Tax Parcel numbers for the Site are 00538200004300, 00538200004400, and 00538200004500. The Public Land Survey System location of the Site is Section 23, Township 28 North, Range 4 East W.M. The Project Site is approximately 1.5 acres in size and currently undeveloped. CLIENTS: Kelly Stephens and Jim Hill PROJECT STAFF: Bill Shiels, Principal; Jennifer Marriott, Senior Wetland Ecologist, PWS; Richard Tveten, Senior Ecologist; and Aaron Ellig, Ecologist. FIELD SURVEY: Talasaea Consultants evaluated the Site on 12 April 2019 to verify and confirm previous delineations performed by Bredberg and Associates (B&A). CRITICAL AREA DETERMINATION: A critical area assessment was conducted on the property (hereinafter referred to as "Project Site" or "Site") by Bredberg and Associates (B&A) on 25 September 2017. B&A delineated the two (2) wetlands, Wetlands A and B, and rated both as Category IV wetlands. Talasaea Consultants field -verified the previous delineations. Wetland A is an approximately 1,450 square foot (sf) closed depressional system with very little vegetation rooted within the wetland boundaries. Wetland B is an approximately 9,000 sf depressional wetland that extends off -site to the east, approximately of which 2,390 sf occurs on the Project Site. HYDROLOGY: Hydrology for Wetlands A and B is provided by stormwater inputs from both 100th Street SW and 23rd Ave W as well as surface runoff from the immediate areas onsite. Currently, stormwater is piped through a culvert into the northwest corner of the Site where it is released to sheet flow across the Site. SOILS: The NRCS maps one (1) soil type on the Site. Soil at the Site is Alderwood-Urban land complex, 2 to 8 percent slopes. This soil type is included on the Snohomish County, Washington Hydric Soils List published by NRCS due to hydric inclusions that are a minor component of this map unit. VEGETATION: Upland vegetation consists of mainly mixed -age red alder forest with salmonberry, vine maple, and false lily of the valley as dominant species in the understory. Wetland A is sparsely vegetated due to overhanging upland vegetation. Dominant species in Wetland A include salmonberry and lady fern. Wetland B is larger and more heavily vegetated with red alder, black cottonwood, salmonberry, skunk cabbage, lady fern, great betony, tall mannagrass, and Watson's willow -herb. PROPOSED PROJECT: The proposed project consists of a new manufacturing building with associated parking and infrastructure in the western half of the Site. Access will be provided off both 1001h Street SW and 23rd Avenue W to provide double access to the Site for fire access. This minimum distance off 23rd Avenue W dictated the location of the entry off 100th Street SW. Stormwater will be addressed consistent with the Department of Ecology (DOE) stormwater manual, as outlined in the Engineer -prepared documents. This will include the use of Low Impact Development (LID) techniques where feasible, a detention vault, treatment modular wetland, and two (2) discharge locations into the wetland buffer. 6 March 2020 Copyright © 2020 Talasaea Consultants, Inc. 1807 CAR V4 Page i