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SECTION VIII: PERMANENT STORMWATER CONTROL PLAN <br /> A. OFF-SITE ANALYSIS <br /> A site reconnaissance was performed by Brian Kalab of Insight engineering on <br /> October 6th, 2017 to verify the downstream flow paths and observe any drainage problems <br /> downstream of the site. The sky was partly cloudy and overcast with a temperature of 62 <br /> degrees. <br /> The site is currently vacant and exists as residential landscaping. The site contains <br /> one drainage basin that flows to the east. Per NRCS survey of Snohomish County, the <br /> project site contains Alderwood-Everett soils that have a hydrologic classification of Type <br /> "C" and Indianola type soils that have a classification of Type "A". No visible on-site <br /> drainage problems were observed at the time of field investigations. <br /> Upstream Analysis <br /> Based on the site reconnaissance and the topographic survey of the site,the off-site area <br /> entering the site is minimal. The sites to the southwest are at a high point and most of the <br /> runoff flows away from the proposed site. Refer to the Downstream Analysis Map attached <br /> in the next page for more details. <br /> Downstream Analysis <br /> The runoff from the existing site flows northeast through multiple neighboring properties <br /> before entering the existing drainage system along Greely St. The runoff then flows to the <br /> north for about 330 ft, then turns to the east for about 400 ft before entering Glenwood <br /> Creek and flowing north. This is where the downstream analysis was completed. There do <br /> not appear to be any restrictions or erosion problems within this distance. <br /> In the mitigated state, the runoff will be infiltrated into the underlaying soils. <br /> Insight Engineering Co. -Stormwater Site Plan 6/22/2022 <br /> -21 - <br />