Laserfiche WebLink
<br />The channel is designed as grass-lined, having 4:1 side slopes ,md <br />a 10-foot wide by 1.5-foot deep low flow channel. The channel will <br />be 3pproximately six to seven feet deep i'lnd 100 feet wide. TWo <br />drop structures will be required directly west of College Avenue <br />in order to resolve vertic<ll conflicts with the proposed sewer line <br />relocations. <br /> <br />i'ls part of the Regional Dri'linage Improvements for the Plum Street <br />Sub-Basin. <br /> <br />Modifications of existing utilities will be necessi'lry to <br />resolve conflicts in several locations. The existing 3D-inch City <br />waterline which is located along the west toe of slope of the BNRR <br />embankment will have to be lowered below the proposed culvert <br />invert elevation. The existing 30-inch connection between the two <br />trunk sewer lines located adjacent to the above descrilJed waterline <br />will have to lJe relocated as well. Modifications arc also <br />antioipated west of College Avenue for the 21-inch trunk sewer <br />Which passes under the College Avenue bridge. <br /> <br />Improvements to the Droke Road crossing consist of four 10- <br />foot wide by 5-foot high box culverts utili~ing a seven-foot head <br />water depth. Grading to transition the entrances to the existing <br />channal will be required both upstream and downstream of the <br />crossing. A berm along the east side of the Creek at the upstream <br />end of the culvert is necessary to channel flows into the proposed <br />crossing. To develop the assumed headwater depth of seven feet <br />minor regrading of Drake Road will also be necessary. <br /> <br />Improvements Upstream of Drake Road <br /> <br />Improvements in this reach alsO include the BNRR embankment <br />stabilization detailed 1.n the aforementioned Chen and Associates <br />Stability Analysis. Brietly, this stabilization consists of <br />flattening out both the up$tream and downstream sldpF.lopcS of the <br />embankment to 3'1. It is also recommended tllat a ".,epa'J'" lJarrier <br />be constructed within the embankment lJelow the flood level on the <br />upstream side. <br /> <br />Several needs are addressed with these improvements. '1'0 <br />protect the condominiums located just south of Drake Road, berming <br />is required on the northwest side of the Creek. Berming is also <br />needed around several houses located upstream of Taft Hill Road. <br />The major improvement 1.n this reach is dn on-stre3m detention <br />facility located upstream of Taft Hill Road. This detention area <br />has been designed to simulate the inadv...rtent pom]j'j{J whidl <br />currently occuni here, with the flow over 'raft Hill Road L>eing <br />eliminated. 'fhe 'raft Hill Road crossing requires three ')-foot wide <br />by 5-foot high box culverts. Approximdtely nine ",;r"5 will b.. <br />needed for the pond. <br /> <br />crossinq Imnxg~ements S~uth of Rolland Moore P~rk <br /> <br />'I'hese improvements consist of ~ combindtion siphon/flume <br />structure and berrning at the New M..rc')r ('",nill -'Inri a ("'[)ml>in"tjnn <br />check/spill structure ~nd floodway spill and stilling ~ond at the <br />Larimer County Canal No.2 cl-ossing. The New Mer,-,,,r Callal f".iphon <br />wa:; sizeG to carry the ditch f~o'," CIS determined in the S..,1"ing <br />Creek M,ljor Drainageway Plan, iln<l requires i1. ,/fl-inuh RCP. 'I'lw <br />Larimer County Canal No.2 improvements ',.Iere pl:eliminal-ily designed <br /> <br />The remaining improvements, Which are upstream of 'taft Hill <br />Road, include an improved crossing at the Pleas3nt Valley 3nd Lake <br />Canal and berming around several nearby structures. '1'h(' crossin'] <br />lmprOVl<mellt will lJotH';ist or a 60" RCF siphon and a concrete flllme. <br /> <br />H <br /> <br />" <br />