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Using the inflow hydrographs generated from the "Runoff" <br />program for developed conditions, the "Extran" program is <br />used to produce discharge hydrographs for the 25yr-24hr <br />design storm event. <br />Additionally, since the north and south detention ponds <br />are to be constructed using the criteria for "Wet Ponds", <br />specified in Section 4.16.1, of the DCSS, an additional <br />��dLl <br />permanent storage volume is required to be divided off' <br />between the wet cell and open cell. Th"Rrmanent-storage's�"k " N,(,,9KJ <br />' 1 <br />YOLUffle is defined as_.being 50 percent, of. the required i5 }�`�, &-e <br />detention storage volume. Out of this permanent storageU equ'�? I <br />f (l u <br />volume, a minimum of 60% must be contained in the wet 1yc 50 G,Cr <br />�..i cell area of the pond with the remaining permanent Z r`dh <br />storage being contained in the open cell portion of thae, r,^HI„1 4' <br />u <br />pond. �� 0 <br />�a Jdu <br />t.�rP rnos�dy,� <br />In order to meet the various sizing requirements outlined PCB h ki�tl� <br />in Section 4 of the DCSS, the ponds were initially sized eP } e (C <br />/I/i%u ( <br />to contain the peak runoff volumes generated by the � } u��Vy! <br />"Runoff" program. The stage -storage information was thanC)M M <br />entered into the "Extran" program to model the outilow2q� <br />r/Q <br />performance of the ponds and to determine the minimum ��d'h1�1y}cfd"r <br />storage volumes required to accommodate storm runoff.14fF lea r �� ' <br />20 � �1 `H't,� <br />eo ell <br />