Laserfiche WebLink
• <br />CRLCULRTIDNS <br />gTIFULnTIr1N Nil. 16 <br />Mr.x lrnuum capacity of the eight 36 Inch culverts at station 31+50 of the <br />IJurthern No. I haul roadr <br />Eight 36 Inch CMP's, 40 feet in length <br />Qrn=CA 2GH7 Civil Engineering HandbooK, page 4-29, equation (54). <br />Orr=Me.x lmum cfs for each culvert <br />C=Coefficent of discharge-C iv 11 Engineering HandbooK, Table 6, page <br />4-40 = 0.64 <br />G=Gr av 1tY <br />F.=Maximum Head = 1.5 feet <br />R=Rrea of pipe 7.1 square feet <br />Orr.=0.64(7.Ift ) 2C32.2ft/sec)1.5ft <br />Orn=44.7cfs <br />Total l)m = 6 x 44.7cfs = 357.6 cfs <br />• Pea-: flows for the 10 year 24 hour event <br />From Espey, Huston b Rssociates, Inc., Appendix R of the CMLRD Mine <br />Permit Application) <br />Q10 Upstream = 269 cfs <br />Q10 Lateral 21 cfs <br />010 Sed. Pond 0 cfs <br />X10 Total 310 cfs <br />Therefore the culverts have an over capacity of 357 cfs - 310 cfs = <br />47cfs or 357cfs/310cfs x 100 = 115% capacity of the 10 year cc^4 hour <br />event. <br />Post reclamation assuming the removal of the sedimentation ponds <br />010 Upstream = 269 cfs <br />X10 Lateral = 21 cfs <br />010 Reclaimed Area 10 cfs <br />Q10 Total 320 cfs <br />• Therefore the culverts will still have an overcapacity of 357 cfs - <br />320 cfs 37 cfs or 357cfs/320cfs x 100 112% of the 10 year 24 <br />hour event. <br />c-~ e <br />~/ ~/~'? <br />