919 E MARINE VIEW DR 2018-01-01 MF Import

919 E. Marine View Drive Apartments #13-4517 LEVEL 1 DOWNSTREAM ANALYSIS A field reconnaissance following the downstream flow path for the site was conducted on November 19, 2013. The observer was Jeff Brown, P.E. The weather was sunny and 48 degrees F. Refer to the downstream analysis maps that are included. Downstream Drainage System Description Runoff on the site sheet flows from west to east. Average site slopes range from approximately 5% to 16%. Existing site vegetation is grass with deciduous trees scattered over the site. Runoff sheet flows across the east property line and continues to the east. At the east property line, the vegetation changes from grass cover on the site to a heavily vegetated cover east of the site consisting of blackberry bushes, trees and thick shrubs (see photo). The vegetation east of the site is dense and makes detecting any existing flow path difficult. The site terrain suggests sheetflow runoff headed east through the thick shrubs. About forty feet east of the project site, an earthen berm about four to six feet high was observed. The berm is oriented in a north-south direction. Runoff that reaches the berm would be intercepted and directed to the south, again through thick vegetation and shrubs. We were unable to follow the path of the berm due to the thick vegetation. No standing water was observed in the berm's swale. The City of Everett's Critical Areas Map Detail is included in the Appendix, Figure 3. It is believed that the forementioned berm and swale is indicated on the Map in "blue" east of the project site. According to the map, this swale heads in a southerly direction and discharges into the Snohomish River approximately 2000 feet downstream of the site. Conclusion No existing or potential drainage or erosion problems were identified during the field inspection or in the resource review. The proposed flow control facilities will be designed to match the proposed drainage runoff to the existing drainage runoff. In conclusion, the proposed project is not expected to have any adverse impacts on the downstream system. March 25,2014 Prepared by: Group Four, Inc.