1450 80TH ST SW 2018-01-02 MF Import

Introduction: This drainage analysis examines h _toric and developed storm runoff rates for the proposed commercial development located in the southeast quarter of Section 11, Township 28 North, Range 4 East, in the city of Everett, Washingrton. The site address is 1480 80TH Street S.W. The 2.72-acre site is bordered by 80 " Street S.W. on the north and commercial developments to the west and east. State Route 526 borders the site on the south. See Attachment 1- Vicinity Map. The following evaluation will consider the historical and developed storm water runoff conditions. Storm water runoff rates were calculated using the SBUH Method, as computed by the Water Works software, version 4 Shareware, by Engenious Systems. Storm detention volumes and the orifice structure design were based on the release of one half the 2-year, the 10-year and 100-year storm event for historical conditions. M.1SDG12001177-SDG.01Wocs10rainegeAnelysls77.doc 3 (^ O