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<br />Table 10,1, Summary of Peak Discharges from Previous Studies for Union and Filmore Basin,
<br />
<br />I.. .' Design "" Peak DisCharge
<br />Point I 10-Year, 24-
<br />I ' Hour
<br />I .,.' ,,' I (cfs) ,
<br />UF-1 ---
<br />
<br />Drexel Barrell ,',' ,....,.'
<br />, ".,..'
<br />Peak DisC<l1/iltge
<br />100-Yeat,2+
<br />Hour
<br />" (cts)
<br />
<br />I'.'..',."'.',..'..'.'., 'Wil~~~ & coI1)J~n~. .,'.., '.' ...,
<br />i:?~~~Dj~~fl:~~ l.peil~Ri$ctll~fge
<br />19"Ye~fjft'" 1q(l.y~f,f4.liour
<br />'Hour" ,.,.,..,...",'...' {cfS}" .", '..,.'.,
<br />(cfl1) ,', " , " ',' '" ,i
<br />390 860
<br />
<br />UF-2
<br />UF-3
<br />UF-4
<br />UF-5
<br />
<br />890
<br />
<br />1,730
<br />
<br />430 950
<br />450 1,000
<br />610 1,380
<br />1,070 2,400
<br />
<br />Table 10.2 displays the basin parameters used by Wilson & Company as well as those used
<br />by RCE, In nearly all of the cases, the RCE T c values are significantly higher than those of Wilson
<br />& Company, However, in those subbasins where the land use is primarily urbanized, there were not
<br />significant differences,
<br />
<br />Table 10,3 presents the results of the Wilson & Company model for the portion of the Shooks
<br />Run basin upstream of the Van Buren Ditch and the RCE model for the 100-year event The RCE
<br />estimates are significantly lower than those of Wilson & Company, This is a result of the changes in
<br />the T c parameters which would result in a delayed and attenuated peak discharge. The longer T c is
<br />justified by the fact that significant portions of the watershed, particularly the uppermost part, are
<br />covered by native vegetation, Resulting estimates of time of travel for sheet flow in these regions
<br />alone approach the T c estimated previously, It is recommended that the longer T c be used which is
<br />a more realistic estimation of subbasin lag times,
<br />
<br />10.3 Resource Consultants & Engineers, Inc,
<br />
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