Laserfiche WebLink
<br /> <br />4 <br /> <br />model demonstration on January 18. The UDFCD representatives expressed concern <br /> <br /> <br />that flows over the downstream embankment crest might attack the right bank of the <br /> <br /> <br />river due to the flow direction of water over the crest In the model. <br /> <br />They suggested a second model configuration to change the downstream crest to a <br /> <br /> <br />V-shape. a horseshoe or straight across so that water overtopping the crest would <br /> <br /> <br />flow directly downstream. The present design would Include right bank rlprap <br /> <br /> <br />protectton with the present model configuration. Ben Urbonas further suggested <br /> <br /> <br />conalderatlon of the boat chute In the middle of the embankment rather than on the <br /> <br /> <br />west bank. This. however. has been vetoed by white water boaters. <br /> <br />During the discussion that followed. Clltf Pugh of the USBR and Ron Rossmll1er of <br />WWE made the following potnts on the pros and cons of these two suggesttons. <br />1. The present downstream embankment conflguratton now has good flow lines. w <br />The current runs parallel to the crest at lower flows and angles towards the <br />west bank at higher flows. Both patterns naturally lead boaters to the next <br />chute. From 100 to 800 cfs, he flow velocities are such that boaters can slowly <br />paddle away from the downstream crest to line up with the second chute or they <br />can stay In the first pool If they so desire. <br />z. A straight or slightly curved crest at right angles to the channel banks would <br />direct the flow downstream of the embankment crest parallel to the river banks <br />or towards the centar of the river. As a note. WWE discussed reducing the <br />angle of the downstream embankment crest with the river bank to reduce the <br />erosion potenttal with Clltf Pugh last December. The conclusion reached was <br />