Laserfiche WebLink
passage and a usable hydraulic feature during typical low flows. During the mid -range flows <br />the low flow channel and part of the high flow would be submerged. During run -off the <br />high flow channel would create a larger, more usable hydraulic feature (a hydraulic jump or <br />wave train), and at extreme flood the river will overflow the shoulders of the structure. The <br />downstream side of these shoulders are stepped to provide seating during normal flows and <br />to prevent the formation of dangerous hydraulics during extreme flooding. <br />Merilow Clianncl <br />High I�lo�% :Cli:annel <br />l.o« l�low Channel <br />Figure 9. The upstream view of the U- structure shows how it is designed to accommodate <br />varying flow levels. <br />Low Flow <br />The low flow chute is designed to create depth and a defined riffle channel at <br />lower flows. This chute provides boat passage for numerous craft at lower <br />flows. Past experience has shown that depth of flow, capacity, and control <br />of the flows are well defined, at lower flows, by this channel. Figure 10, <br />shown below, is an example of a low flow channel with flow in it. <br />26 <br />