Laserfiche WebLink
<br />(e <br /> <br />I <br />I <br /> <br />~- <br /> <br />~ <br />I <br /> <br />Table 1. <br />Flow Characterisitics at <br />Selected CrosS Sections <br /> <br />Section <br />Number <br /> <br />Water Surface <br />Elevation, ft. <br />Existing Improved <br /> <br />592.2 593.3 X\~ <br />582.2 583.3 \ ,.\ <br />577.7 576.7 ",0 <br /> <br />Main Channel <br />Velocity,ft/sec. <br />Exisitng Improved <br /> <br />Right Overbank <br />Velocity, ft/sec. <br />Existing Improved <br /> <br />27.9 16.0 ,/ <br />23.1 22.8'/ G\ <br />20.4 28.-3 'x"'" <br /> <br />49+60 <br />45+50 <br />43+20 <br /> <br />10.5 14.3 <br /> <br />5.2 Proposed Improvements <br /> <br />Using the flood plain limits and hydraulic values under existing <br /> <br />conditions as a basis, flood control improvements were. designed to remove the <br /> <br />Water Treatment Plant from the flood plain and protect the Water Treatment <br /> <br />Plant and Emergency Storage Pond from damage due to high velocity flows. <br />Because the existing concrete ponds will hold only treated water ready to be <br /> <br />discharged, it is not necessary to protect them. Fill and levee protection <br /> <br />elevations at the Water Treatment Plant site were selected as described in <br /> <br />the following paragraphs. <br /> <br />High velocity flows in alluvial channels are subject to the following <br />items affecting the depth and velocities of flow: <br /> <br />1. Normal depth of flow and effects of backwater or drawdown. <br /> <br />2. Superelevation on channel curves. <br /> <br />3. Degradation or aggradation of the channel bed. <br /> <br />4. local scour caused by obstructions, r.onstrictions or on the outside <br /> <br />of bends. <br /> <br />5-4 <br />