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li <br /> 1 <br /> 204 <br /> $. <br /> , <br /> t <br /> It <br /> H(FT.) <br /> 500 <br /> f f 400 <br /> Te (MIN.) <br /> =- 300 EXAMPLE f_- 200 <br /> Height =•100 Ft. 150 <br /> N — 200 Length=3,000 Ft, - - <br /> w = Time of concentration:14 Min. <br /> = 150 — 100 <br /> -- <br /> �`' 10,000 '-- 60 <br /> 70 _ °� -_ <br /> �— .`EX-4 M,o so <br /> S�1 S �0 ` ,� - - z -- 40 <br /> z 4 ........... i- 5,000 4 <br /> 1 '�., h 3 0 <br /> �:� a 3,000 <br /> u' Note: _ F- __ <br /> 0 20 Use nomograP t •r na .I = 2,000 w T 20 <br /> basins with well d than u' "v "— 15 <br /> I a for overland fl 9w o „ e 1 500 Q- <br /> I Q 1350 <br /> F — 10 <br /> ear th,and for mowed grate`'+�.`.d- F- — — 10 <br /> o _ side channels. `�� 1,000 u_ <br /> For overland flow, grassed sur- :�- 700 + ` $- <br /> O _ faces, multiply Tc by 2. <br /> — 6 <br /> — 5 For overland flow, concrete or 5"."---_ w <br /> 5 <br /> x — 4 asphalt surfaces, multiply Tc <br /> — <br /> by0.4. — 300 4 <br /> w ' For concrete channels,multiply <br /> s Tcby0.2. ` 3 <br /> 2 — 200 <br /> -- 150 — 2 <br /> L141 ___ I <br /> 1 <br /> Based on study by P.Z, Kirpich, <br /> Oli . Civil Engineering, Vol.TO, No G, June 1940,p.362 <br /> C i iA f;T 2 <br />