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Table IV-4 (Continued) SWMM Channel Length Slope Number (n) (n/n) Channel Type' Comments 147 1,550 .038 N 148 3,300 .032 N 149 1,825 .026 N 150 1,750 .034 F 151 400 .025 N 152 400 .025 N 4 153 200 .025 N 4 154 200 .025 N 4 155 200 .025 N 4 156 500 .040 N 4 157 700 .107 N 158 2,875 .018 LSW 159 2,300 .030 F 160 6,400 .014 C 161 5,400 .024 C 162 1,050 .030 C 163 1,160 .048 C 164 4,800 .031 C 165 1,920 .015 C 166 1,550 .013 C 167 1,000 .090 C 168 2,000 .009 MCD 169 3,700 .025 F 3 Table IV-4 (Continued) SwMM Channel Length Slope Number (n) (n/n) CJ.anllel Type' Conuneids 170 2,500 .040 N 4 300 Series 1 .020 DP 5 See Table IV-3 for description of channel type abbreviation. 2 Channel elements lie east of Indiana Street 3 Channel element 169 is a composite of elements 144, 145, 146,202, 203, 204, and 205. Element 169 is used for peak flow and total volume calculations. The other elements may be used to replace 169 in the model for detailed analysis of the ponds. 4 Channel element 170 is a composite of elements 152, 153, 154, 155, 156, 207, 208, 209, and 210. Element 170 is used for peak flow and total runoff volume calculations. The other elements may be used to replace element 170 in the model for detailed analysis of the ponds. s Design points are "dummy elements" used to faciljtate output data management. They do not have any effect on flow routing. The design points, however, must have physical characteristics (shape and Manning's "n" value) associated with them to be used by the model. Because the length of the design point elements is so short compared to other elements, the shape and Manning's "n" characteristics do not affect the output of the model if they are within an order of magnitude of those used for the channel elements. The characteristics shown in Table IV-3 show values that are consistent with those used for the other types of channel configurations but are easily distinguishable when examining SWMM output.