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' REVISED <br /> 7/30/85 <br />' <br />~- installed and compacted in lifts of 3 feet or less. Following <br />' construction of the embankment, the outlet works and tributary diversion <br />di <br />h <br />ll <br />d <br />E <br />l d <br />i <br />i <br />i <br />i <br /> es were <br />nsta <br />. <br />ng <br />ng contro <br />tc <br />e <br />neer <br />uring construct <br />on <br /> consisted of inspection, surveying and compaction-testing of fill <br />' material at the direction of a qualified registered professional <br /> engineer. The design of Sediment Pond E is shown on the Fish Creek <br /> Tipple Sedimentation Pond E As Built Plan View Map (Map Ex 8-I), Ditch <br /> and Dam Profiles Map (Map Ex 8-2), and Figure 3, Typical Cross Section <br />' of Emergency Spillway. <br /> Diversion Ditches <br />1 <br /> Diversion ditches which direct runoff to sedimentation ponds are <br />' designed to carry the peak discharge of the 10-year, 24-hour event. <br /> Ditches used to divert undisturbed drainage are designed for the <br />' 25-year, 24-hour event. Design parameters are given in Table 5, Fish <br /> Creek Tipple Diversion Ditch Design Specifications; Figure 4, Typical <br /> <br />~ Diversion Ditch Section; Ditch and Dam Profiles Map (Map Ex-8-2); and <br />' <br />~ Ditch Profiles Map (Map Ex 8-3). The ditches are triangular or <br /> trapezoidal in shape, with side slopes of 2:1. The Manning flow <br />' equation was used to determine the depth of water at the design flow <br /> rate. In all cases, ditches are designed with a flow velocity less than <br />' 5.0 feet per second, to prevent erosion of the channel. Lining of <br /> earth, vegetation, aggregate or riprap is provided as appropriate. <br />' Freeboard of at least 1.0 feet has been provided in all ditches, which <br /> is conservative in consideration of Rule 4.05.3, but necessary to <br /> prevent breeching of ditches on steep slopes. Topsoil is used in berms <br />' of the ditches, and will be used to reclaim the diversions when no <br /> longer needed. Survey control of gradients and slopes was utilized <br />' during construction. <br />' Culverts <br />' All culverts are designed to safely pass the 10-year, 24-hour runoff <br />event, without developing a head of water on the pipe entrance. Inlet <br />~ control is assumed for all the culvert designs. F1 ow capacities were <br />1 <br />-5- <br />