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<br />3 <br /> <br />Thus, for chute flows up to 100 cfs, the drop Is 3.75 feet. At higher boating flows <br /> <br />when water overtops the USAGE dam and the downstream embankment, the drop <br /> <br />reduces to 3.0 feet at 400 ets, then Increases to 3.5 feet at 2,500 cfs. <br /> <br />At flows of 500 to 800 cfs, boats would exit the upstream chute and follow the cur- <br />rent generally 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 />get hung up on the crest. A gentle shove with a paddle would get them back Into the <br />current which had measured velocities of I 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 USAGE 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 suggested <br /> <br /> <br />forming the rock and grout on the downstream face of this crest to the same shape <br /> <br /> <br />as the sill at the existing USACE dam crest discussed above that worked so well to <br /> <br /> <br />smooth 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 USAGE 100-year flood of 16,400 cfs that was taken during the <br />