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_ . <br /> The standards requirc a minimum of 30% of the wrtpond design volume <br /> to be provided aspermanent dead stonge and for the -ntire wetpond <br /> design volume to be rcached during the wetpond desig�: storm (the 6 <br /> month, 24-hour stortn). Routing of the wetpond design storm's <br /> developed hydrograph through the pond is raryirai to �rrify that the <br /> wetponcl desi�n volume is reached for the wetp�nd desig�i storm. The <br /> siu of the pnmary orifice can be dxreased aa neceasary to a minimum <br /> allowable orifice size of 1 inch, to achieve ena�gh �ive storage. lf a 1 <br /> inch orifice dcesn't reault in the required stora�e in the pond, then the <br /> percentage of the wetpond desi�n volume provWed as dad storage must <br /> be increased untit the combinauon of dad storage and peak live stonge <br /> (during the wetpond design atorm)equals the wetpond design volume. <br /> The stage-storage relationship of the pond ia e+equired to ahow that the <br /> pond has the capaciry to store the rcquircd wetpond pem�anent storage <br /> volwne and any live detention volume. <br /> City standards rcquire a two�ell wetpond deaign, wi.h an open water <br /> celi or wetvault/tank followed by a vegetated treatmeM cell. The <br /> drainage calculations must state the volume of dead stonge which wiil <br /> be provided in each ccll and the depth of dead storage in each cell. <br /> A maaimum of 7096 of the wetpond design volume may be associated <br /> with the open water celi. The maximum water depth in the open water <br /> cell or wetvault/tank must range between 3 and 6 fat. <br /> A minimum of 30?b of the required permarent storage volwne, with an <br /> average depth not excceding 1.33 feet, is required to be assceiated with <br /> this cell. The maximum allowable water depth in the treatment cell is 2 <br /> feet. <br /> The required detention volume must be provided as live storage in <br /> addition to the dead atorage. Live storage provided to meet wetpond <br /> design volumc requirements counts towards required detention volume. <br /> The control structure must ensure that detention release rates do not <br /> exceed allowable release rates �that the detained volume in the pond <br /> reachcs or exceeds the wetpond design volume for the wetpond design <br /> stortn. Orifice calculations must be submitted showing that the control <br /> structure is meeting both thesc requirements. <br /> In the calculation package, curve number and time of concentration calculations are <br /> required for pre-development and post-development conditions. <br />