Laserfiche WebLink
c..-',.r.. ... :.'i r! Concl ucl nos: <br />/~.s shown in Table 1, the velocity of flow ir. v-shaped diversion ditches <br />s:tth a 1~ g.radient or less is not excessive. Flow velocities .`or the 2-yr, <br />2L-'rr. event does no[ exceed t'ne recommended r;aximum velocity of =v FPS. Phis <br />clearly illustrates that for .. °_-vr, 24-hr event, ero::ion of the diversion <br />di: c':: is v~r; unli.hely_ keep in s~ind that :pie 2-~~r, 24-hr event is the oac <br />th:u t~n~_ State ree,ulaCions require that we ~iesi~,n for. Also, mosC of our <br />diversion ditches are short-liced...one to two :acres. Therefore, the majori[,• <br />of our diaersions, over the nears, will not exnarience n greater event. <br />'Ihe flow velocities for an event as great as a IrJ-yr , 24-hr event do not <br />exceed recommended values until the watershed exceeds 600 acres. *]ost of the <br />..atersiieds diverCed at the Trapper 71ine are less titan this . Therefore, it can <br />`.~e said that the majori R• of our di.versinn ditches C1% gradient.) should not. <br />erode even for events as great as 10-vr, 24-hr events. <br />lf~ner>_ the gradient of a drainage ditch exceeds ] "~, '1'ahle ° shoes the ma>:imu:u <br />- allow'a51e watershed area to avoid producing: a flow -ate in eacesr. of '~ feet p^_r <br />• second. During a two-year, 24-hear even[, a gradient up to 5% could be used <br />for a watershed of 640~acres. This table can he used in associa*_ion, with the <br />area drainint; [o a diversion ditch [n define Lhe ma>:i*num accen.abl=_ ,,^,radier.c. <br />;• <br />T-2 <br /> <br />