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<br />5. Infiltration Rates <br />Infiltration rates were assumed to he the same as <br />the soil permeahility rates available from the <br />Soil Conservation servic,,(31 for the various soil" <br />.....ithin the drainage basin. <br /> <br />Subbasin parameters for future developFlent, specifically detention <br />and depreSSion storage, Manning's roughness coefficients, and <br />infiltration rates, were assigned the values indicated previously, <br />However, tho percentage of impervious area and the overland <br />flow length for subbasins are dependent on the type and extent <br />of future development, A conversation with Mr, Curt Smith, <br />Planning Director for the City of Fort Collins, revealed that <br />any residential development within the urban growth area shoulfl <br />be projected to a density of 4 to 6 units per acre. Therefore, <br />for the fully dev~eloped condition in the West Vine Drainage <br />Basin, all developable Gub~re~G e~st of Overland .rail were <br />projected to this density Which results in ~n average impervious <br />area of 40 percent of the total subarea. In FlOSt resid€'ntial <br />areas, lots arC graded to drain to the street and to the hack <br />lot lines. Based on this ?remise, an average overland flow <br />length of :25.0 ft. "'''H determin€d t<! he applicable to the tully <br />developed subbasins. Due to the lack of control over development <br />on C.S.U, pro~rty, it was mutually agreed with the TeChnical <br />Committee that the City would attempt to reach an aqreement with <br />C,S,U, to limit peak rat"s of runoff to peak rates g,-"ne"ated by <br />the current develop=nt. Therefore, thE' fully developed con<'lition <br />west of Overland Trail ...'as ~ssumed to egual the E'xistinq dC'velop- <br />"""nt cO'lctiticn, <br /> <br />IV,F. <br /> <br />Resultli <br /> <br />RC'sults of the ~ydrologic ~naly:Hs are ill\lstri\tc(1 schel1lAlticilllY <br />on the peak flo"-' discJlarg.o profilos l"bcled FHJurcs 2 Clnd 3. <br />T~lrcc chaclcteristics of these dl.scharqp profil...g des+o>rve ",ention. <br /> <br />-H- <br />