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• 52.50 cubic feet per second. The separate channel sections for Permanent Diversion No. 1 are shown on Figure 3, Refuse Disposal Area Drainage Plan, and the Drainage and Sediment Control Map, (Map 20). Section A is designed as a trapezoidal shaped, vegetated channel with a 5-foot bottom and 2H:1V sideslopes. The channel section extends far approximately 800 feet at a 1.4 percent slope. The design flow velocity is only 4.4 feet per second, therefore, a vegetative lining provides adequate protection for this section. Section B is designed to the same configuration as Section A, extending approximately 270 feet at a 1.9 percent slope. The design flow velocity is 5.0 feet per second, therefore a vegetative lining will be utilized to provide erosion protection for this section. Section C is also a trapezoidal shaped channel with a 5-foot bottom width • and 2H:1V sideslopes. The channel extends approximately 500 feet at a 4.0 percent slope. The calculated flow velocity (6.4 fps) exceeds 5.0 feet per second, therefore, rock riprap (D,~ = 9 inches) is installed in Section C to prevent erosion. Riprap is placed to an approximate depth of 20 inches along the channel bottom and sideslopes. In order to stabilize the riprap, appropriate bedding material was placed and spread to a depth of four (4) to six (6) inches prior to riprap placement. Design details and channel characteristics for each channel section are illustrated by Figure 4, Permanent Diversion No. 1 - Design Detail. Refer to Table 16, Permanent Diversion No. 1 - 100-Year, 24-Hour Hydrograph Analysis, at the end of this section, for computer printouts. Refuse Collection Ditches The refuse collection ditches are located around the perimeter of the refuse disposal area as shown on Figure 3, Refuse Disposal Area Drainage . Plan. For design purposes, three (3) main refuse collection ditches have been delineated: 107