9432 ‎(2)‎

• UCREFRP Catalog Number: 9432
• Author: Modde, T. and M. Fuller.
• Title: Feasibility of Channel Catfish Reduction in the Lower Yampa River.
• USFW Year: 2002.
• USFW - Doc Type: Vernal.
• Copyright Material: NO

IN REPLY REFER TO:
BA/WM
SP-30(A)30.
Mail Stop 60189
Memorandum
To:
From:
Subject:
United States Department of the Interior
FISH AND WILDLIFE SERVICE
Mountain-Prairie Region
MAILING ADDRESS: STREET LOCATION:
Post Office Box 25486 134 Union Blvd.
Denver Federal Center Lakeuvod, Colorado 80228
Denver, Colorado 80225
i
TAUE?
AMEEWA? i
si ¦

Colorado River, Biology Committee
George Smith, Water Resources Division, Region 6
Redlands Passage Options
During July a group of experts (listed below) conducted a site visit to the
Redlands diversion structure to re-explore the options for passage. This memo
documents the options discussed during the visit and presents a summary of the
options status.
Option 1 - Move the structure to a different location where a full river,
diversion would not be required. This option was felt to be very expensive
due to the additional canal length, and may not solve the problem because at
low water it would be difficult to force water into the diversion canal.
Option 2 . Build a small bypass canal around the structure on river right.
This option was discussed very little because of problems with land ownership,
unproven technology, and a possibility that during high flows the river could
create a new river channel through the bypass channel. This option would also
require some sort of diversion structure at the upstream end of the bypass
canal.
Option 3 - Place a number of rock structures in the river downstream of the
diversion to create a series of pools and riffles which slowly increases in
elevation to match the elevation of the diversion structure. This option was
discussed and considered unsuitable because of the need to build a chute
through the series of rock structures. During high spring runoff, the rock
structures could shift and settle. The shifting and settling would render the
structure unworkable.
Option 4 - Build a smaller version of Option 3 about 200 feet downstream of.
the diversion structure which would allow fish passage into the Power canal.
This option would be much less costly in terms of material and sheet piling
could be placed to narrow the structure and increase stability. The option
would place the fish in the Power canal which is problematic. This could be
solved by screening the Power canal below the diversion structure, but'adds
the cost of the screen plus the long-term operation and maintenance of the
screen. The option would also not lend itself to fish traps and/or fish
excluders which are necessary for ongoing research.
B-1