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ed <br />irking <br />Event No. (n)Intensity (in/hr)Duration <br />Sec' s <br />Q = CIA <br />of s <br />1 <br />2 <br />3 <br />4 <br />5 <br />6 <br />8 3 600 14.9 <br />6.1 1,200 10.95 <br />4.9 1,800 8.79 <br />4.1 2,400 7.36 <br />3.5 3,000 6.28 <br />3.1 3,600 5.56 <br />Inflow - outflow volumes and detention volumes for each storm <br />duration <br />Inflow Volume *Qn + 1 <br />2Ql <br />ted + <br />Outflow Volume= \ + i <br />Ql <br />ted + <br />n <br />Ql <br />I <br />t cd <br />rainfall event number <br />peak rate for initial event where d = t^d <br />time interval d - ted seconds ^ <br />developed time of concentration <br />See hydroqraph <br />Event No. (n) <br />1 <br />2 <br />3 <br />4 <br />5 <br />6 <br />14.9 <br />10.95 <br />8.79 <br />7.36 <br />6.28 <br />5.56 <br />13,410 <br />14,619 <br />8,370 <br />11,333 <br />5040 <br />3280 <br />Event No 1, a 10-minute duration storm with an average <br />?nteL??; of t.3 inches per hour, is the critical storm duration <br />and when maximum detention volume is required. <br />Pond should be designed to store 5,040 ft.^ and an outlet designed <br />to discharge 9.3 cfs at Qa (max. head) <br />Wwm s’ • -i ■*. Y'- <br />■ ■ !’ > — <br />taiy <br />V - -V <br />mvmm <br />■ :vb v.V.y i :• ••■? ‘ > • <br />«ll0 ; <br />Event No. <br />Inflow