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I I I I I I I I I I I I I I I I I I I !H:l'lIB 5 - PtI.':U1IJlE RE lElElMIHOO CAPACIlY (F aJlIl Q{ A armlUlE G!A1E 'Ile graJirl.c solnH"" presented here (Charts 1.7 am 1.8) tas the advantage of being appli,."hl" to any grade (5), croos slope (Sx), rwghness coefficient (n) am fl.ow sprmd in the street (T), 10trlle giving a direct reading fran a single chart. 'Ile standard curb opening :iJl1et is illusttated by <hut: 1.6 and is defined as having a gutter depression aprm W feet wide at the :iJl1et opening which exteIIis at least W feet upstream and doIonstream fran the opening, has a depressim depth (a) equal to \V/l2 feet at the curb fact, and a an-b opening height (h) of at least 0.5 feet. 'Ile graIb as presented by Chart 1.8 is IBsed m a dt:p.e..J.m aprm width (W) equal to t\<<) feet am depression depth (a) equal to t\<<) inches. 'Ile ~ c.roes str~ sectim can aloo be analyzed using an effective flaw spread as will be ni<r11ssed later. '1te entire length of the :iJl1et opening oust be free of any Obstruct1C11. An exanpl.e in dotted lines i lln<ll'Tates the use of Chart 1. 7 . 'Ile depth of flow, dw, in the street section of the p:lint W (two feet fron the an-b face) is the starting point. 1. &Iter with dw = Sx(T-2) feet at top of Chart 1.7. 2. Follow vertically down to a line representing Kmn1ngs ''n'', llClI1lIlily 0.016. 3. fobve lmizmtall y across to lcmgi.tudina1 slope S. 4. Follow vertically down to flaw spread T; this establ.islEs a horizontal line for the """"lpl{> at haOO. 5. If Qi/Q is given, enter with Qi/Q (Upper right), follow lmizmtally across to line A,ror line for Sx, which ever is intersected first. 6. }bve vertically down to lower nm:gin (..nere Qi/Q = 0.1) and then diagonally to intersectim with line fran Step 4. 7. Follow vertically down to find the required length of inlet Li. 8. 'Ile horizmtal line in Step 4 can be extended to line 1.3 to find the needed an-b opening to achieve 100 percent interceptiCII; fran intersection with line 1.3, nvve vertically down to :iJl1et length for that case. 9. If length of inlet is given, enter with that lmgth, JIDYe vertically up to lxrizmtal line establi.slEd in Step 4, then diagonally to Qi/Q ,. 0.1, then vertically to Sx or lane A and horizmtally across to find Qi/Q. Chart 1.8 has been caDJUted to give the relative increase in total flow for various croos slopes and values of T >Ihen the gutter is cross sloped steeper than the street. It is 00sed on a gutter two feet wide with a cross slope of 1 :12. For pn-abo1ic street sections, the above procedure my be used, but it is T""'"~~ to caJJjXlte the equivalent straight cross-slope section and flaw spread. First solve for cross slope using as equatim for flow in a triangular channel using Q, n, d, and S obtained using the parabolic sectim: 17