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. <br />draintioe continucs sloping westerly Ihroudh thick vegetation and eventually �nters a <br />wedand that empties inte ;i stream that is a Iribut.�ry to swamp creek. <br />Basin f3 <br />Upstream drainnge was analyzed for 1/4 mile in nccordance with City of Everett <br />standards. I3asin E3 has a significant upstream drainage area that is influenced by runoff <br />from a nearby �olf course at Katsch Park, neighboring properties to tlie north thtu sheet <br />Flow to a rvetland sveam and a new development on 93"' St. SW that also cortributes to <br />Ihis strenm after being detained and ireated. Along the southern border of the golf <br />coursc, a shrub FilleJ ditch, running east to west, exists. Drainage from the southern <br />portion of the golPcourse enters the ditch and travels west, where it enters and exits a 12 <br />inch concrete culverL Prom here, drainnge continues westerly until it hits a low point <br />where it conver��•� with drainaoe that appears to be come from the golf course's water <br />features. The dr, nage travels south in a wedand su�:am d:at is a tributary to Swamp <br />Creek. <br />Dowusircam drainngc was analyzed for I/�} mile in accordance with City of Everett <br />standards. Drainage from the eastern portion of the site enters a type 5 stream that is a <br />tributary to Swamp Creek and hcads south.'fhe downstrelm conditions am overgrown <br />with wedand vegetation ancl brambles. Downed Vees tangled with vegemtion appe�r to <br />conu�ibute to the restriction of stream ilo�v aud contribute to the wedand. <br />South of the proposed sile, the developmen[ of Augusta Woods exists. Here, drainage <br />travels under 95°i St. SW through what appears to be a 54" wide arch culvert. Drainagc <br />exits this cuivert aud continues southerly for approximalely 300 feet befare entering a <br />5'x 10' box culveil under 9G�' St. SW. Tl�c slream continues on in � southerly direction <br />and eventually crosses undcr IQO"' St. SW through a culvert which has two 18"oveiflew <br />risers �vith cone grates on top. It appeairs this drainage eventually enters Swamp Creek. <br />'I'he downstre.un culverts withi�i one quartcr mile appear to be sized adequately for <br />anticipate<I flows. I lowe��er, obsUuclions in the form of downed trees and other <br />vegetation conu ibute to b:ick�vater conditions. Further downstre�m at 100'�' Street, an <br />antiq:iated intnkc structure (18-inch overilow risers indicated above) connected to <br />approximately 300 fcet of pipe (size undeterminecl) appears to restrict !lows, based on <br />vegetation, debris and other field obscrvations. Calculations were nmde to estimate the <br />100-year f1ow and determine an approximate l00 year Flood plain. The flow calculated <br />just passes through the nearest downstream culvert, however bac'avater effects Further <br />downstrcam may cause localized Flooding. As a result, the finished floor elevauions for <br />the proposed units have bcen set to approximately ten feet above the ordinary high water <br />mark in the stream. <br />IV Auulysis and Design o(' Ra�uired Grosion and Scdimenk Control BMPs <br />'I'he soil for the site consisis of fVdenvood Urban Land Complex. Classit7ed as <br />hydrological group "C" accarding to the SCS Soil Survey for Snnhomis•l� Count�•. <br />Alderwuod soil is moderatcly deep over a hardpan and is moderately well drained. It <br />fonned in glacial till. Permeability of tiie Alclerwood soil is moderately rapid above the <br />