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<br />Table 12. Channel, hydraulic, and vegetation components <br /> <br />[n, Manning's roughness coefficient; ft, foot; fils, foot per second; ftIft, foot per foot; ft-lb/s/ft2, foot pounds per second per foot squared; ft-Ib, foot <br />pound; ---, not applicable] <br /> <br /> Vegetation- <br /> susceptibility <br /> Hy- Aver- Slope of Ratio of hydraulic index <br /> drau- age water- radius to average (kv) <br /> lie velo- surface Stream vegetation height (It-Ib) <br />Flood Manning's radius1 city' profile' power <br />frequency n (It) (ltIs) (lt/lt) (It-Ib/sllt') Brush Willow Brush Willow <br />2 year.............. 0.070 2.0 2.6 0.0055 1.78 0.7 0.2 t77 t5.200 <br />10 year ............ .070 5.5 5.1 .0066 11.6 1.8 .6 35.4 5,060 <br />50 year ............ .050 8.0 8.9 .0063 28.0 .8 1,260 <br />IObtained from standard-step computations (Shearman. 1990). <br /> <br /> 100 <br />f- eo <br />0 <br />0 60 0 <br />u. <br />w 50 . <br />a: <br />< <br />:J 40 C <br />0 <br />m <br />a: 30 . <br />w <br />a. 25 . <br />0 <br />z 20 <br />0 <br />() <br />w 15 <br />m <br />a: <br />w <br />a. <br />m 10 <br />0 <br />z e <br />:J <br />0 <br />a. 6 <br />~ <br />0 5 <br />0 <br />u. <br />~ 4 <br />a: 3 <br />w <br />~ 2.5 <br />0 <br />a. <br />::; 2 <br />< <br />w <br />a: 1.5 <br />f- <br />m <br /> 1 <br /> 1 <br /> <br /> <br />n = 0.070, 2.YEAR FLOW, BRUSH <br />n = 0.070, lQ-YEAR FLOW. BRUSH <br />n = 0.070, 2-YEAR FLOW, WILLOW <br /> <br />n = 0.070, lQ-YEAR FLOW, WILLOW <br /> <br />,.,..,,,,, <br />/' <br />........ <br />........ <br /> <br />................................ <br /> <br />"';.... . <br />........ <br />........ <br />/' <br />........ <br />........ <br /> <br />................~ Vege'.'ion--Suacep'ibilily <br />,.,." Threshold <br />.,."'........ <br /> <br />. <br /> <br />n = 0.050, SO.YEAR FLOW, WILLOW <br /> <br />. <br /> <br />o <br /> <br />c <br /> <br />, <br />, <br /> <br />10 <br /> <br />100 1 ,000 10,000 100,000 <br />VEGETATION-SUSCEPTIBILITY INDEX, IN FOOT-POUNDS <br /> <br />1,000,000 <br /> <br />~ <br />, <br />i <br /> <br />Figure 11. Effect of the 2-year and 1 O-year flow on brush and willow for roughness coefficient (n) equal 10 0.070. Also <br />shown is the effect of the 50-year flow on willow for n equal 10 0.050. <br /> <br />24 Method to Estimate Effects of Flow-Induced Vegetation Changes on Channel Conveyances of Str.ams in Central Arizona <br />