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<br /> <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />. <br />. <br />.. <br />. <br />. <br />. <br />. <br />. <br />I <br />. <br />I <br /> <br />3 <br /> <br />Thus, for chute flows up to tOO cfs, the drop is 3.75 feet. At hioher boatlno flows <br />when water overtops the USACE dam Ind the downstream embankment, the drop <br />reduces to 3.0 feet at 400 cfs, then increases to 3.5 feet It 2,500 cfs. <br /> <br />At flows of 500 to 800 cfs, boats would exit the upstream chute and follow the cur- <br />rent oenerally parallel to the downstream embankment crest to the second boat- <br />chute. At 1,000 cfs, the flow depth over the embankment would be 0.8 feet with an <br />approach velocity .of about 3 fps. Thus at 1,000 cfs, some boaters would typically <br />vet huno up on the crest. A ventle ahove with a paddle would oet them back into the <br />current which had measured velocities of 1 to 2 fps. Ben Urbonas suggested making <br />the crest about 10 feet wide so that boaters who wished to could walk along the <br />crest to the river bank or to the second chute. This is a good suggestion. <br /> <br />At boating flows over 500 cfs, the flow over the USACE dam helps create a current <br /> <br /> <br />which leads boaters exiting the first chute directly to the second chute, even with- <br /> <br /> <br />out paddling. A few boats stayed on the east side adjacent to the Englewood Intake <br /> <br /> <br />and floated over the downstream embankment crest. A few attendees suogested <br /> <br /> <br />forming the rock and grout on the downstream face of this crest to the same shape <br /> <br /> <br />es the sill at the existing USACE dam crest discussed above that worked so well to <br /> <br /> <br />amooth out the flow patterns over the upstream crest. Flow velocities approaching <br /> <br /> <br />the downstream embankment crest were measured at 2 to 3 fps. <br /> <br />The maximum flow rate used on January 31 was 5,000 cfs. The group watched a <br /> <br />video tape of the USACE 10o-year flood of 15,400 efs that was taken during the <br />