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<br />The only anticipated conflict with the new street is near Monte Street, extended, <br />where the Chicken Creek floodplain widens into the proposed development area. <br /> <br />To determine the depth of flooding or the floodplain limits at any location <br />in the field, the following procedure should ~e used: <br />Locate the ground point at which the depth of flooding or the <br />floodplain 1 imit is to be established on the 1" ~ 200' flooded <br />area map. <br /> <br />Flood Elevations <br />Flood water surface elevations for the 10-,50-, 100-and500-yea r floods IlldY be <br />fou1d in four se~arate locations in this report. The Flood Frequency-Elevation and <br />Discharge Data table, Tables 4 and 5, list these elevations at selected reference <br />points. The Flooded Area plates 3 . 7 give the plan view of the flooded area <br />on a contour base map and the high water elevations for the 100.year flOOd can <br />be interpolated from this. The Flood Profile Plates, 3 . 14 show the streambed <br />elevation and the high water elevations for all four frequency floods. Also <br />the Cross Section Plate 15 shows a graphical representation of the high water <br />elevations at typical valley cross sections throughout the study reach, <br /> <br />Determine the elevation of the water surface at the selected <br />ground point from Tables 4 and 5 by interpolating ~etween the <br />water surface elevations given for two adjacent cross section <br /> <br />rcference ~oints. <br /> <br />Using the closest monument for elevation control, determine <br />the water surface elevation at the ground point by standard <br />leveling technique. The floodplain limit is esta~lished where <br />the water surface elevation intercepts the ground surface. <br /> <br />The FlOOd Profiles may be used in areas where controversy arises over the lOO-year <br />flood boundiir'yon the Flooded Area plates. Since the Flood Profile plates give <br />the elev~tions and distance or stationing from a known point, tne nlgn water <br />elevations can be surveyed on the ground to alleviate any discrepancies on the <br /> <br />The approxi~~te flood depth can be calculated by subtracting the ground <br />elevation estimated from the contour map from the prevlously de tel'1l1inedwater <br />surface elevation. <br /> <br />naseoop. <br /> <br />To locate the edge of the floodplain ~y simpl e scal ing methods, rlLea,;ure the <br />distance on the map from two or more physical features that can be identif1ed <br />both on the map and in the field to the edge of the floodplain. The flOOdplain <br />limits can then be establ ished ~y laying out th" IDeasured distances in the <br />field. <br /> <br />LL~__LOC2.tion of Floo~ed Areas <br />The flood profile elevations and floodplain limits shown in tnis report can be <br />easily transferred to field locations by simple 5urvey methods using the <br />established monumentation or by scaling from physical features shown on the map. <br /> <br />~25. <br /> <br />-26- <br />