6317 EVERGREEN WAY HOGLUNDS 2018-01-02 MF Import

t 11. There is a sani[ary scwer main and a storm drain line in the vici!;Ity of this work which needs to be located and marked prior to con^truction beginnina. 12. No trees will be aliowcd within, the City Utility Easemen[ located on the east side of the properiy. 13. Storm water treatment is requircd when 5,000 squurr; feet or �nore of hydraulically-coniiected pavement is creaied and/or rede��eloped by u project. Treatment of storm wr.ter runoff from hydraulicaUy- connected pavement must occur, per City standards, prior tc disci�arge of the storm water from the site, or to a strearr:, weiland, or underground infiltratior� system. ➢ If suitable soils exist on qie site, Low Impact Development techniques (e.�-, permeable pavement, bioretention areus, and di;:, ^rsion lhrough stream/wetland buffers) may be used to avoid creating hydraulically-connected puveme�:t from a storm water treatment stnndard. ➢ Frcm � storm water treatment standpoint, for a paved area to be considered hydraulically- disconnected, storm �vater runoff from ut least the 6-month, 24-hour storm must be fully retnined and/or infiltrated. The options for trealment of runoff from hydrnulically-connecled pavement arc: a. an infiltration basin with pretreatment*, if suilable soils exist on the site b. a wetpond c. n constructed wedand d. 1 slorm water technology that hns received a GULD (General Use Level Designation) from the Wnshington State Deparlment of �cology for either basic or enhanced treatment, with pretreatement* * ncceptable F: etreatment systems are either a wet vauit or lank designed in accordance with City slpndurds and containing 30°/v of the �-!nonth, 24-hour storm as dcnd storage, or a pretreatment system that has obt�ined a GULD for pretreatment from the ��ash;ngton Stnte Department of Gcology 14. 5torm wate: detention is required �vhen 5,000 sGunre fec� or more of hydraulically-connected imper�. ious area is created by a projecl. ➢ If suit�ble soils exist on thc site, underground infiltration systems (e.g., infiltration trenches) or Low ]mpa�.t Development techniyues (e.g., splash blocks nermeable pavement, bioretention areus, rain watet ::arvesling) may be used to uvoid crcating hydraulically-connected impervious area from a storm �vater detention standpoint. Section 3-2.2 of the City's 3tormwater Management Manual lists site fmd design criteria that must be met Y from a storm water delention stundpoint, i'or an impervious area to be considered hydraulicnlly- disconnected, stonn ��ater runoff fram lhe 50-year, 24-hour stor:a must be fully retained and/or infiltrated — without resulting in significant potential For c�dverse effects from the infiltrated water (suci� ns slope sutur�tion or migration to cra�vlsp�ces and/or basemenls). However, if the o;�-site soils clnnol support full infillration of the SO-year, 24-hour stomi, then partial infiltrration may still be feasible to help meet allownble storm wuter rclease requirements.