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<br /> Table 3 <br /> Summary ofOhcharges <br /> Dre.1ne.ge <br /> >r.. Diechar~e in Cubic Feet per Second <br /> Locat;ion (a". mi.) la-year 50_year 10O_year SaC_year <br />F~nchman Creek """ 14900 <br />at Highvl\,." 385 m 2750 6200 <br />North Fork henchman 6970 l2640 <br />Creek at lIlOuth "4 2240 5200 <br />South Fork Frenchman 3740 6870 <br />Creek atlQO\lth 6J 1170 2800 <br /> <br />l!y~aulic AnaJs.ia <br /> <br />A.~&ly"e. of the hydraulic characteristics ot Frenchman Creek vere <br /> <br />carried out to provide estimates of the water surface elevation. of floods <br /> <br />of the selected recurrence intervala along the river. The water surface <br /> <br />elevations were computed through use of the Corps of Engineers HEC-2 step <br /> <br />backwater computer program (Reference IO). CraBS sections for the back- <br /> <br />\later analysis were :oeasured from tWO-fOot contour topographic mapping. <br /> <br />~e approximate location" of the croa" sections used in the backv&ter <br /> <br />analysis are shovn on the flooded area maps, plates 3 thru 18, and the <br /> <br />flood profilea, platea 22 thru 28. The reference points "",d lOO-)'ear <br /> <br />floodelevationsarelistedinTable4onpages16and17. <br /> <br />Roughness factors (MMnings "N") for use in hydraulic computations <br /> <br />Were assigned on the basis of field inspection of flOOd plain aress. <br /> <br />French~en Creek roughness factors arc 0.04 for channel and 0.05 for the <br /> <br />overba.nk areas. A detailed description of the hYdraulic ano.lysis ia in_ <br /> <br />cluded in the Technical Addendum. <br /> <br />l3 <br /> <br />14 <br />