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<br />TABLE 6. <br />FLOOD WARNING TIMES FOR THE HIGHWAY 6 CLOSURE <br />(Times in Hours and Minutes) <br /> <br />Closure Invert Elevation <br />Discharge at Closure Invert -- <br /> <br />- 4545.1 ft. msl. <br />23,100 cfs <br /> <br />GAGE <br />Hwy. 52 <br />Co. Rd <br /> <br />(upstm. ) <br />(dnstm. ) <br /> <br />10-YEAR <br />12 hI's <br />5hrs,15min <br /> <br />50-YEAR <br />8hr,10xnin <br />2hr,30xnin <br /> <br />100-YEAR <br />'7hr, 35min <br />2hr,20min <br /> <br />500-YEAR <br />6hr,15min <br />1hr,40min* <br /> <br />* The warning times list,~d in Tables!5 and 6, for the <br />500-year floods, are comput,~d from 'the second occurrence of <br />the high stage alarm, as the larger of th.~ two peaks will re- <br />quire that the closures be made. <br /> <br />The computed flood warninlJ times listed in Tables 5 and 6 <br />are longer than those listed in Part 1.4 of Appendix F of the <br />"Wiggins 0 & M Manual, 1989"" For example, the travel time <br />between Highway 52 and Wiggins is given as 4 hou.rs for the <br />100-year flood, in that reference. This is similar to the <br />travel time calculated by the Corps and shown in Table 1. <br />The flood warning time provide,d to Wigginl3 by a flood warning <br />gage at Highway 52 is given as more 'than '7 hours in Tables 5 <br />and 6 for the same magnitude of flood. The reason for this <br />difference is that the values given in the CWCB are the <br />travel times for a constant discharge and those provided in <br />this report were developed by routing flood hydrographs and <br />include rise time at both locat:ions and flood wa.ve propaga- <br />tion, as well as travel time" <br /> <br />3.2 Flood Warning Options <br />Two options for the configuration of the wiggins Flood <br />Warning System, have been di,scussed with the CWCB. They are <br />summarized as follows as Options 1 and 2. These options will <br />be further discussed in Pari; '7. "Comments and Recommenda- <br />tions" . <br />Option 1 - This option consist:s of an automated flood detec- <br />tion device at the County ROiid Bridge (d01rlnstream gage) and a <br />staff gage, only, at Highway 52. The network of volunteer <br />observers, outlined in Appendix F of the "Wiggins 0 & M <br />Manual, 1989", would read the staff gages and rain gages dur- <br />ing floods. <br />Option 2 - This option consist:s of automa"ted flood detection <br />devices at both Highway 52 and t:he County road crossing. The <br />network of volunteer observers, outlined in Appendix F of the <br />"Wiggins 0 & M Manual, 1989"" would read "the staff gages, at- <br />tached to the alarms, and the rain gages during floods. <br /> <br />3.3 Rock Creek Flooding <br />Since a right bank tribul;clry; Rock Creek, <br />Creek downstream of the furt:hest downstream <br />gage, discharges from this st:ream could reach <br />tected. The HEC-1 model, as calibrated to <br /> <br />enters Kiowa <br />flood warning <br />wiggins unde- <br />the discharges <br /> <br />8 <br />