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The West Section 16 Ditch from station 0+00 to 45+00 is trapezoidal in cross section <br /> with a 2 foot bottom width, left side slope ratio of 1H:1V, a right side slopes ratio of <br /> 7H:IV, and depth of at least 0.5 feet. This segment is a vegetated channel. <br /> The West Section 16 Ditch from station 45+00 to 63+57 is trapezoidal in cross section <br /> with a 10 foot bottom width, left side slope ratio of 4H:1 V, right side slope ratio of <br /> 2H:IV, and a depth of at least 1.0 feet. This segment of the ditch is a vegetated channel. <br /> The location of the East and West Section 16 Ditches can be found on Map 12. <br /> Section 16 Permanent Channels <br /> The Section 16 watershed is comprised of two post-mining channels, the Section 16 Fill <br /> Ditch and Trib F respectively. The locations of both channels are presented on Map 12 <br /> and Figure Exh. 7-14S-2, and the channel profiles are presented on Map 33 and 33B. <br /> The assumed hydrologic condition for both channels is the post mine condition when the <br /> entire Section watershed is reclaimed and reporting to the Section 16 Pond. <br /> Section 16 Fill Ditch <br /> The Section 16 Fill Ditch conveys a very small area of Section 16 reclamation areas into <br /> the South Collection Ditch ultimately reporting to the Prospect Pond drainage system. <br /> The ditch is designed to meet the requirements of Rule 4.05.3 for drainages less than one <br /> square mile. The drainage area of this basin is about 12.4 acres, all of which is now <br /> Phase III released. The steepest portions have a slope of about 17.8 percent. The overall <br /> length of the channel is about 860 feet. <br /> A SEDCADTM model has been included which evaluates the peak flow for the 10 year, <br /> 24-hour storm event. The channel configurations for the 10 year, 24 hour storm event for <br /> the Section 16 Fill Ditch is summarized below. <br /> Section 16 Fill Ditch <br /> Peak Average Channel Side Erosion <br /> Station Flow Sloe % Type Slopes Protection <br /> CFS <br /> Station 0+00 1.77 17.8 Trapezoidal 3H:1V Riprap, <br /> to 8+60 12' bottom D50 = 12" <br /> Because the flow is so small in this watershed, the SEDCADTM demonstration had to use <br /> a triangular ditch (zero bottom width) with 3H:1V side slopes, but as construction <br /> dictates, the ditch may have a bottom width up to 12 feet based simply on the minimum <br /> width of a dozer blade. <br /> Page Exh. 7-14S-3 Revision Date: 1/20/21 <br /> Revision No.: TR-145 <br />