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Ycrmanent I;rosion f�ediment Control <br />• All stormwater systems �aill be closed convey.mces. Any scdiment that collects <br />in thc wct tanks or wct ponds will not bc subjected to any velocities greater than <br />fps during thc 1Q0-ycars stonn to minimize suspension of scdiment in thc <br />stormwatcr. Rock protection at thc outfalls have becn installed. <br />� Maintenancc for ouUet protection at the outfalls will include: inspection and repair as <br />� ncccssary; rock addilions as ncccssary to maintain thc intcnded function and periodic <br />, cicaning of thc encrgy dissipatcr as scdiment builds up. <br />V. Analysis and llesign oi Required RunoIT Control I3MP's <br />The access and parking arcas, and boat y.u�d work arcas havc bcen subdividcd into a <br />numbcr of drainage sub-hasins for storm�vatcr analysis. Thc basin bo�mdarics and arca <br />calcidations are provided in Uic figwes in Appendix A. <br />5lormwater Conve��:�nce <br />� llcsign Criteria for Storm�.v.�ler Conveyancc 5yslem <br />� <br />( • All Lxisting and Proposcd convcyancc systcros shall bc dcs'gn lo com�cy <br />4� runoff Crom lhc 25-ycar storm. (St.mdards 4- I) <br />� . Tight-lined com�cyance systems rccciving runoff from relatively small and/or <br />highly impervious drainagc cu�cas shull be sizcd using ilows dctcrmincd using <br />( thc rational method. (Stnndards 4-I) <br />� . A backwatcr analysis may bc rcquircd for a proposcd or existing pipc systcm <br />C if thc ability of thc pipc systcm to convcy the pcak rate of runoff from the 25- <br />ycar design storm cvcnt may bc affcctcd by tailwatcr conditions anywhcrc in <br />� the pipc systcm. <br />( . Siructw�es such as catch basins and manholes for proposed pipe syst.;ms, mus( <br />� providc a minimum of 0.5 fcct of frceboard bctwccn Ihc hcadwatcr surfacc <br />(h��draulic �i:idc linc) and thc tup of Uic suvctin•c for ilo�v from thc 25-ycar <br />srorm. 1-lowevcr. su�uctures m:q� ovcrtop for Ilow resulting from a 100-)'car <br />stornt. <br />C:ilculations fur tilorni��•alcr Cunrc)'ancc Syslem <br />Rational mcthod :ind thc local IDf curvc f'or City ol' G��crctt wcrc uscd as a <br />hasis for calculating thc 25-yccv dcsign storm Ilow. <br />l3ack���ater analysis was run using ihc 35-year desi�n slorm ilow using thc <br />slormwatcr trcatmcnt systems Uy-pass ovcrllow cicvation as taihvatcr conu�ol. <br />A summary of this inl'ormation is pro��ided in Tabic 1. 13ackup calculations <br />:mii dct.iiled hack���aler :malysis are proeidcd in r\ppendix B. <br />3- <br />� <br />