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connected impervious ar?a from a stormwater detention standpoint Section 3-2.2 of ihe <br /> City's Stormwater Management Manual lists site and design criteria that must be met. <br /> 24 From a storm�vater delention standpoinl, for an impervious area to be considerud <br /> hydraulically-disconnecled stormwater runo(f from the 100-year, 24 hour storm must be <br /> fully retained and/or infiltrated—without resulting in significant potential for adverse eifec,s <br /> (rom ihe infiltrated water (such as slope saturation or migration to crawlspaces andlor <br /> basemenis) However, if lhe on-site sc�ls cannot support full infiltration of the 100-year, 24- <br /> hour stonn partial infiltration may slill be feasible to meet allov✓able stormwater release <br /> requiremenis. <br /> 25 f3ecause lhis site is located within the Silver Lake drainaye bas n, lhe options for storm�vater <br /> lreatment tor ihis project are: <br /> a. a wetpond or constructed wetland in series with a vegetated swale, <br /> b a wetpond or constructed v�edand in series�vilh a SMI StormFdter, <br /> c a wetpond or �onstrucled wetland in series with an alternative storm�vater treatmenl <br /> technology deemed, by the City o( Everett, to be technically equivalent to the above options <br /> 2G The required stonnwater lreatment vulume (or wetponds is the volume of developed runoff <br /> (rom the G-incnth, 24-hour storm. City standards�or�vetponds allo�v a maximum of 85°6 of <br /> this volumc lo be provided as underground dead storage in a a�etvault or tank. A minimum <br /> of 15°a of the stormwater treatment volume, however, must be provided in an open-to-the- <br /> air vegetated treatment cell. Piease see the City's Stormwater Management Manual. <br /> Chapt?r 3-3, for more iniormation. <br /> ?� All stonmvaler facilities shall be designed in accordance with applicable City standards <br /> and/or design policies. <br /> 78 An NPD[S (National Pollutant Discharge L=liminalion System) permit, administered by <br /> Washington State's Deparlment of Ecology, will be required for cleanng and grading <br /> actiwties on this site if the site area disturbed by land alleration activities is greater than or <br /> equal lo one acre. <br /> 29 All catch basins in the project must be stenciled with a message similar to "Dump no water. <br /> drains to Silver Lake" This message is lypicalty spray-painted onlo the nround ad�acen( lo <br /> the catch basin �vith the use of a stencil. The stenciling needs to ba repealed, <br /> approximately annuzlly, when the pain e�ears off <br /> 3U fhe applicant is proposiny to provide storr�water tre�tment and detention by mod�fyin� the <br /> existing stonmvater treatmenUdetention system at 1431 - 112"' StreeL This proposal is <br /> acceplable, provided that the modified facilities meet current City standards for both <br /> projects. From the City's standpoint, maintenance oF the etortnwater facilitias al 1431 - <br /> 112"' Street will continue to be the responsibility of Ihe property owner. Any sharing of <br /> maintenance activities or costs must occur via private agreement. <br /> 3 i A pedestrian circulation system for the site must t�e approved by the Planning Direclor an l <br /> Traf(ic Fngineer prior to the issuance o(any building permits, Walkways must allow <br /> pedesVians and wheelchairs to ��in easy access from sidewalks and bus stops to buildin_i <br /> entranced through the use of paths which are physically separated from vehicle tra(fic anc <br /> S <br />