|
<br />26
<br />
<br />TECHNICAL MANUAL
<br />
<br />Using the procedures described on pages 5 and 6, the following values
<br />for the required parameters were obtained:
<br />
<br />Drainage area (A)=9.0 mi2
<br />The drainage basin was outl ined on the topographic map and the enclosed
<br />area was planimetered.
<br />
<br />Basin sl::;r;e (SB)=64 ft/mi (see fig. 1),
<br />Length of main channel (L) from site to basin divide along longest chan-
<br />nel was measured to be 6.8 mi,
<br />
<br />0.85L=6.8(O,85)=5,8 mi
<br />O,lOL=6.8(O, 10)=0.68 mi
<br />Elevation at 5.8 mi upstream=6,400 ft
<br />Elevation at 0.68 mi upstream=6,075 ft
<br />SB=(6,400-6,075)~(5,8-0,68)=64 ft/mi
<br />
<br />Streambed slope (SS) = 33 ft/mi (see fig, 1).
<br />
<br />Contour downstream from site=6,050 ft
<br />Contour upstream from site=6,060 ft
<br />Oistance between contours=O,3 mi
<br />SS=(6,060-6,050).O,3=33 ft/mi
<br />
<br />The basin parameters are inserted in the appropriate equations which are
<br />solved as follows:
<br />
<br />Ql0
<br />
<br />144AO.52c5 0.336=
<br />B
<br />
<br />891AO."825 0.154=
<br />B
<br />
<br />144(9,0)0.528(64)0.336
<br />891 (9.0) 0.482 (64) 0 . 154
<br />
<br />144(3.19) (4.04)=1 ,860 ft3/s
<br />
<br />Q50 =
<br />
<br />= 891 (2,88) (1,90)= 1,,880 ft3/s
<br />Ql00=1,770AO.C635 0.086=1,770(9,0)0.463(64)0.086
<br />B =1,770(2,77) (1.43)= 7,010
<br />
<br />Q500 =5,770Ao.432=5,770(9,O)0.432=5,770(2,58)=14,900
<br />
<br />ft3/S
<br />ft3/s
<br />
<br />Ole =35.555-0.462=35.5(33)-0.462=35.5(0,20)= 7.0 ft
<br />05C =52.155-0.500=52,1 (33)-0.500'"52,1 (0.17)= 8,9 ft
<br />0100=59.355-0.517=59,3(33)-0.517=59,3(0,16)= 9.5 ft
<br />0500=77.355-0.553=77,3(33)-0.553=77.3(0,14)=10.8 ft
<br />
<br />If desired, use a graphical solution for Ql00 and 0100'
<br />Ql01--refer to figure 3,
<br />
<br />For A=9 mi2 and 5B=64 ft/mi. From figure 3, Qloo=7,010 ft3/s.
<br />
<br />D10;--refer to figure 4,
<br />For 55=33 ft/mi. From figure 4, 0100=9.5 ft.
<br />
|