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<br />Table 12. Channel, hydraulic, and vegetation components
<br />
<br />[no Manning's roughness coefficient; ft, foot; ftIs, foot per second; ftlft, foot per foot; ft-lb/slft2, 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 (ft.lb)
<br />Flood Manning's radius1 City1 profile' power
<br />frequency n (It) (ltIs) (1tI1t) (1t-lb/sIfl2) Brush Willow Brush Willow
<br />2 year "............ 0.070 2,0 2.6 0,0055 1.78 0,7 0.2 177 15,200
<br />10 yeaL........... .070 5.5 5,\ ,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 />10btained from standard-step computations (Shearman, 1990).
<br />
<br /> 100
<br />r- 80
<br />8 60 0
<br />u.
<br />w 50 .
<br />a:
<br />0<
<br />::;) 40 IJ
<br />0
<br />(f)
<br />a: 30 .
<br />w
<br />a. 25 .
<br />0
<br />z 20
<br />0
<br />()
<br />w 15
<br />(f)
<br />a:
<br />w
<br />a.
<br />(f) 10
<br />0
<br />z 8
<br />::;)
<br />0
<br />a. 6
<br />..:.
<br />0 5
<br />0
<br />u.
<br />~ 4
<br />ci 3
<br />w
<br />~ 2,5
<br />0
<br />a.
<br />:::;; 2
<br />0<
<br />w
<br />a: 1,5
<br />t;;
<br /> 1
<br /> 1
<br />
<br />
<br />n = 0.070, 2-YEAR FLOW, BRUSH
<br />n "" 0.070, 10-YEAR FLOW, BRUSH
<br />n = 0.070, 2-YEAR FLOW, WILLOW
<br />
<br />n = 0.070, 1O-YEAR FLOW, WILLOW
<br />
<br />,.,.,.,.",,.
<br />/"
<br />
<br />..................",
<br />
<br />...'"
<br />...'"
<br />.",,.,.,.,.; .
<br />
<br />...'"
<br />...
<br />...'"
<br />
<br />.........",< Vegelalion-Suscepfibility
<br />",,,,'" Threshold
<br />,;",'"
<br />
<br />.
<br />
<br />n = 0.050, 50-YEAR FLOW, WILLOW
<br />
<br />.
<br />
<br />o
<br />
<br />IJ
<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 />Figure 11, Effect of the 2-year and 1 O-year flow on brush and willow for roughness coefficient (n) equal to 0.070. Also
<br />shown is the effect of the 50-year flow on willow for n equal to 0.050.
<br />
<br />24 Method to Estimate Effects of Flow-Induced Vegetation Changes on Channel Conveyances of Streams in Central Arizona
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