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ele~ation at toe point with the app~oprlate water surface elevation On theprofiIBplateorthereferencedatati!lble. Figures 10 and II show the height of the lotemedlateRcgional Flood forexlstlngcondltloos at two locatIons in the study reach. Extensive flOOding would occur in the area betweon Interstato Highway 225 and Sixth Avenue. Although the Interstate bridge would not significantly obstruct 11 large flood, 11 portion of the flow would continue north along the east side of the lnterstato highway. The existing structures beneath Sixth Avonue, pIctured In figure 4, would not pass the Intermedlato Regional Flood discharge and floodwaters would cross In"n aree west of thecul"6r1'S. FlowilcrossSixth AveouewQuldbe threefeetdeopatfholowestpolntandaoout 1,100 feet wide. Theflow ,"auld continue 1n a northerly direction west of the existing channel, thr<>ugh an apartment house area nowunderdevelopmenf and re-enferthe channel near Interstate Highway 225. SlxthAvenuewouldl>etotally closed during a major flood event and portions would likely be badly damaged. A trailer pllrkon the right bank of Toll Gate Creek near the downstre~ end of the studY reach would also be flooded. Chambers Road and Qylncy Avenue would also l>e imp~ssdble during a future lergo flood. Chambers Ro",d Is r..lsed only slightly above the flood plain. The crossings there would likely be washod out and would coasetoobstruct flood flows. Utilities would probably be affected, such as damaged weter mains at stream crossings, and sanitary sewers and power poles naar the chanrw3l. The Hlghllrw3 Canal cros_sW"st Toll Gate Creek as an elevated flume that would probably be washed out during a . ,. . " ~. EaST TOil G.-.Te Creek m.-.jor f load. The canal i ntercop.s ,,0 en, I re ow~, and the excess Is returned to the channel downstream. Duringa''''ljor flood the cenal might overflow at "umorous locations In the gonaril' area. ThElN3tional Wo3ther Service rad3r3t Limon, Colorado is capable ofdetectlngaroasof lntenseprocipitatlon in the Toll GateCreel<bes1n andagenerill alerttothedilngerof tlilshtloodlng Is then CO<TYOUnicated to news media i1nd local oftlcials. The We8ther Service Forecast Office iltDenver SUDPllesroutine forecasts four timcs dillly as weil asspe clal forecilstsofseverestonns. Rapid stream rIse isaflondhazilrdintha study reach, as overbank flows from a major stonn would occur 1n from two to four hours. Flood duration would be very short. Althnugh depths of flooding are generally In the limits of one to three teet on the flood plain, velocities of five feet per second would COI1VI'IOnlyoccur during a major flood. It 15 generally cOMidered that depths of three feet combined with velocities In exces~ of throe feet per second produce substantial flood hazard. The main channel flows are generally in excossof elghf feet per second and erosion dilm"'ge to the Channel and Channel structures would be great. " "