Laserfiche WebLink
flow as discussed previously. It produces a 10 -year peak flow velocity of 4.5 fps in its <br />steepest section, which is below the SEDCAD maximum permissible velocity for that <br />ditch slope. <br />The next segment, which is the main stem of the West Pit Fill Ditch, is designed for the <br />100 year flow as required by Rule 4.09.2 for a ditch in a valley fill. It has a 100 year flow <br />that requires D50 of 12 inches. After being joined by the East Taylor Pond Ditch, the rip - <br />rap sizing increases to 24- inches due to the larger combined flow and the steeper gradient <br />(25 %). Below that point the combined flow is the largest but the gradient has flattened <br />somewhat to 17 %, allowing the rip -rap size to reduce to 21- inches. <br />The East Taylor Pond Ditch has a gradient of about 3.5 percent which allows the use of a <br />vegetative lining, as demonstrated in the attached 100 year storm SEDCAD output. Peak <br />velocity of 6.5 fps in the 100 year event is below the SEDCAD maximum permissible <br />velocity the vegetative lining for this slope gradient. <br />Exh.7 -14F -3 Revision Date: 9/12/2012 <br />Revision No.: TR -96 <br />