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I I I I I I I I I I I I I I I I I I I 42 Redlands Parkway The hydraulic characteristics of the Redlands Parkway site are slightly different from the others (Table 7). The reach averaged slope is steeper at low flow than at moderate flow due to a riffle at the upstream end of the site. Although the slope decreases at moderate flows, the shear stress increases because of the greater water depth. The highest flows yield the greatest reach averaged slope, depth, velocity, and shear stress, as at the other sites. Figure 20 shows that the flow accelerates over the riffle at the upstream end of the site at all discharges, and the slope becomes relatively flat at the downstream end at low flows due to the ponding effects of a downstream riffle. At high flows, this riffle is drowned out and the slope remains relatively steep at the downstream end. It also shows that initial motion of Dso occurs at a discharge of approximately 420 cms (14,825 cfs) and significant motion occurs near 1100 cms (38,825 cfs). These are approximately the 1.81 and 4.0 year flood respectively. RM 162.4 This site is similar to the others in illustrating a general increase in reach averaged velocity, depth, slope, and shear stress with discharge (Table 8). Figure 21 shows that the flow mimics the bed topography at low flow, but at higher flow the topographic features are drowned out and the slope becomes more uniform. It also shows that initial motion of bed material occurs near a discharge of 575 cms (20,300 cfs) and significant motion at flows near 1300 cms (46,000 cfs). This is approximately the 1.42 and 6.5 year flood respectively. Although the grain size is similar, the slope of this site is less than that at the Redlands Parkway site, therefore a larger discharge is needed in order to result in a similar boundary shear stress.