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Norksheet -I: Graphical Peak Discharge method <br />.Project <br />SDH#4 AREA "A" <br />Location <br />Circle one: Present Developed <br />1. Daca: <br />By DGA Date 7/1/93 <br />Checked Date <br />Drainage area .......... Am ° 0.0011 mil (acres/640) <br />RunoEF curve number .... CN ~ ' 89 (From worksheet 2) <br />Time of concentration .. Tc 0.15 hr (From worksheet 3) <br />Rainfall distribution type II (L, IA, II, III) <br />Pond and swamp areas spread <br />Chroughout watershed ...... 0 percent of m (_ acres or m12 covered) <br />2. Frequency ............................... <br />3. Rainfall, P (24-hour) ................... <br />~. Initial abstraction, Ia ................. <br />(,Use CN vith table 4-1.) <br />5. Compute Ia/P ............................ <br />6. Unit peak discharge, qu ................. <br />(Use Tc and Ia/P with exhibit 4-_) <br />7. Runoff, Q ............................... <br />(From worksheet 2). <br />8. Pond and swamp adjustment factor, Fp .... <br />(Use percent pond and swamp area <br />with table 4-2. Factor is 1.0 for <br />zero percent pond and swamp area.) <br />9. Peak dlscharge, qp ...................... <br />(Nhere qp ° quAmQFp) <br /> <br />Yr <br />in <br />Storm 1 Storm 2 Storm 3 <br />lOYR 25YR <br />1.4" 1.8" <br />in 0.247 .247 <br />0.176 0.137 <br />csm/in 840 860 <br />in 0.55 0.86 <br />1.0 1.0 <br />cfs 0.51 0.81 <br />41-3 <br />D-4 (210-VI-TR•55, Second Ed.. June 1986) <br />