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Table 7-7-1 Summary of Ditch Requirements (continued) <br />Ditch Number Discharge Slope Minimum Minimum Other References <br /> (cfs) (%) Depth Top Width Specifications <br /> (feet) (feet) <br />SSa 9.45 3 1.24 4.71 Triangular' C:\SEDCAD3\CR7\PNDSA6, SEDCAD+ ERODIBLE <br /> CHANNEL DESIGN Ditch SSa <br />SSb 8 0.94 4.68 Triangular'•' C:\SEDCAD3\CR7\PNDSA6, SEDCAD+NONERODIBLE <br /> CHANNEL DESIGN Ditch {check dams) SSb <br />' Sideslopes of 3 horizontal to l vertical. <br />= Residual clastic armor materials provide protection (riprap). <br />' Sideslopes of 2 and 3 horizontal to I vertical. <br />Discharge from a 100-year, 24-hour precipitation event (a permanent ditch). <br />' 3H:1 V Sideslopes, 6-foot-wide bottom. <br />Riprap Dm„ = 15.00 inches (in), Dso = 12.00 in, D,o = 4.00 in. <br />Analyzed with a 29% slope, the maximum accepted by SEDCAD+ Simons/OSM Method. <br />Dm° = 11.25 in, Dso = 9.00 in, D,o = 3.00 in. <br />Astable substrate was designated for those ditches where low check dams and silt fencing arrest ditch erosion. <br />10 3H:1 V Sideslopes, 8-foot wide bottom. <br />Table 7-7-2 <br />Culvert Discharge <br />(cfs) Stze <br />(inches) <br />5 1.57 6 <br />• 7-~ 10 December <br />