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<br />8.0
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<br />TABLE Ll. -=- SUMMARY OF SW BASIN PARAMETERS
<br />
<br /> DRAINAGE AREA CURVE NUMBER TrME OF
<br />SUBBASIN ~are !]111es) CN CONCENTRATION. Ic
<br />1 0.471 75 0.320
<br />2 0.484 76 0.410
<br />3 0.583 78 0.600
<br />4 0.651 85 0.690
<br />5 0,1,81 84 0.571
<br />6 0.462 83 0.391
<br />7 0.333 82 0.430
<br />8 0.307 81 1.010
<br />9 0.283 88 1. 220
<br />10 0.333 82 0.430
<br />11 0.781 81 0.470
<br />
<br />Results for the 24-hour AMC rI storm are shown in Table 7.3.
<br />At 6,810 cfs for the 100-year discharge at the confluence to
<br />Sand Creek, the new hydrologic analysis is considerable higher
<br />than the earlier study at 3,830 cfs. Division of the basin
<br />into more detailed hydrologic units is thought to be the main
<br />reason for such a large increase. As upper portions of the
<br />basin are well-developed and relatively steep, the discharges
<br />presented here do not seem unreasonable.
<br />
<br /> TABLE 7.3 -=- SUMMARY OF SW DISCHARGES BY RCI
<br /> DRAINAGE AREA PEAK DISCIlARGE(l)(cfs)
<br />LOCATION ll~uare !!!llill 1Q yg 50 YR 100 XR 500 YR
<br />SWl 0.35 270 430 540 760
<br />SW2 0.95 700 1,120 1,400 2,000
<br />SW3 1. 20 81,0 1,340 1,690 2,400
<br />SW4 1.51. 1,020 1,640 2,060 2,950
<br />SW5 1. 90 1,320 2,090 2,600 3,650
<br />SW6 2.19 1,580 2,450 3,040 4,300
<br />SW7 2.1,0 1,760 2,720 3,370 4,700
<br />SW8 2.67 1,990 3,070 3,790 5,350
<br />SW9 3.00 2,190 3,400 4,210 5,800
<br />SW10 3.13 2,260 3,530 4,370 6,200
<br />SWll 3.46 2,450 3,840 4,770 7,000
<br />SW12 4.58 3,320 5,190 6,450 8,700
<br />SW13 1,.89 3,440 5,390 6,680 9,000
<br />SW14 5.17 3,510 5,490 6,810 9,600
<br />
<br />
<br />(1) These values result from the 2l,-hour AMC II storm.
<br />
<br />SAND CREEK -=- ~IAIN STEM
<br />
<br />8.1 WatershE!d Description
<br />
<br />The Sand Creek Main Stem Basin (SM) is located in north eastern
<br />
<br />33
<br />
<br />R€~OURC€ CON~UlTI\NT~ INC
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