7316

• UCREFRP Catalog Number: 7316
• Author: U.S. Army Corps of Engineers.
• Title: Redlands Dam Fishway Feasibility Study, Gunnison River, Colorado.
• USFW Year: 1986.
• USFW - Doc Type: Walla Walla.
• Copyright Material: NO

• B. General Description of Preliminary Alternatives.
1. The nine alternates reviewed at the scoping meeting are
described in the following paragraphs. Refer to Plate 2 for sketches of
the nine alternates, A through I.
2. Alternate A, Experimental Ladder.
A short, experimental ladder could be located near the
existing sluice gates. This ladder would consist of three or four pools,
a fish trap, and mechanical equipment to lift fish from the trap to the
upstream side of the dam. Also, louvers would be placed upstream of the
existing headgates to prevent fish passage into the power canal.
3. Alternate B, Right Abutment Ladder.
A vertical slot/orifice type ladder could be located around
the right abutment of the diversion dam. A siphon pipe would carry water
from the upstream side of the dam. The quantity of water, regulated by a
valve, would provide the proper fish attraction conditions. This alter-
nate also provides louvers at the existing power canal headgates.
4. Alternate C, Two Left Bank Ladders with Fish Passim Through
Power Canal and HeadQates.
Two Denil fish ladders could be located downstream of the
existing sluice gates in the left bank. These ladders would provide fish
passage into the power canal. The upstream ladder would operate when the
existing sluice gates were not open. Under these flow conditions, the
fish would migrate toward the dam and find the fishway entrance. The
downstream ladder would operate when the existing sluice gates were open.
Under these flow conditions, the fish would migrate toward the sluice
gates until the velocity of flow became too difficult to swim against.
The fishway entrance would be placed somewhere below this velocity
barrier. After entering the power canal, fish would migrate to the
upstream side of the diversion dam by passing through the headgates.
This alternate provides a trash shear boom at the power canal headgates
and louvers downstream of the ladders in the power canal. These louvers
should prevent passage of adults toward the powerhouse.
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