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<br />II <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />10 <br /> <br />in the 1986 study was 5,150 cfs. This resulted in a water surface elevation on the <br /> <br />8ruchez property upstream of Wadsworth Parkway of 5365.0. The actual peak <br /> <br />discharge rate from the 1986 study at this location was 4,910 cfs. This reduces the <br /> <br /> <br />water surface elevation upstream of Wadsworth Parkway to :5364.0. <br /> <br />With the Inclusion of the completed improvements at Ketner Reservoir, the peak <br /> <br /> <br />discharge rate just upstream of the C80S Railroad is decreased to 4,540 cfs. This <br /> <br /> <br />reduces the water surface elevation upstream of Wadsworth Parkway to 5362.8. <br /> <br />I"PROVED INLET <br /> <br /> <br />Additional measures to decrease the water surface elevation even further can be <br /> <br />introduced. One of these Is to Improve the hydraullc efficiency of the inlet to the <br /> <br />rail road culvert. <br /> <br />At most culverts, water Is ponded and quiescent upstream of the Inlet. In order to <br /> <br />flow through the culvert, sufficient head (depth) must be built up to accompllsh two <br /> <br /> <br />things: I) change static energy (depth) into kinetic energy (velocity) to allow the <br /> <br /> <br />water to flow through the culvert and 2) get the water from just outside the culvert <br /> <br /> <br />to just inside the culvert (entrance loss). <br /> <br />This entrance loss Is a function of the inlet geometry and is measured in terms of an <br /> <br /> <br />entrance loss coefficient times the velocity head (V2/2g), where V Is the velocity in <br /> <br /> <br />feet per second and g Is the acceleration due to oravlty. Efficient entrance oeome- <br /> <br />try can reduce the entrance loss coefficient from 0.9 to 0.2. <br />