WSP02208

• File Number: 8240.200.10.B
• Description: UCRBRIP Program Summaries/Status Reports
• Basin: Colorado Mainstem
• Date: 8/1/1995
• Author: UCRBRIP
• Title: Status Report
• Water Supply Pro - Doc Type: Publication

Fish ladder at Redlands Diversion Dam

Biologists believe dams and water diversion structures in the river are one of the primary reasons
for the decline of the Colorado squawfish, razorback sucker, humpback chub and bonytail chub.
These barriers have fragmented migration routes of endangered fish, cutting their historic range
by 75 percent. The fish are no longer able to access preferred spawning, feeding and winter habi-
tats. Once they leave the area they cannot return. Upstream of such barriers, these fish are nearly
extinct.

Redlands Diversion Dam is a 12-foot structure on the Gunnison River three miles upstream of the
Colorado River confluence. Owned by the Redlands Water and Power Company, the dam was
constructed in 1918 for irrigation and power generation. Colorado squawfish, razorback sucker
and bonytail were once abundant in the Gunnison River above Redlands, especially near Delta,
Colo. Around 1950, these native fish began to decline dramatically in this area. The dam now
blocks the fish from accessing more than 50 miles of their historical habitat. U.S. Fish and
Wildlife Service biologists first proposed developing a fish ladder at Redlands in 1982.

A final environmental assessment was completed for the fish ladder and is available through J one
Wright at the Bureau of Reclamation (970-248-0636). All city and county permits and approvals
have been obtained. The U.S. Bureau of Reclamation is currently renegotiating the long-term
operation and maintenance contract for the passage structure. The ladder will be built beginning
in October 1995, and should be operational by April I, 1996.

Action:
Date:

Contract to be awarded for construction of fish ladder.
Sept. 29, 1995.

Action:
Date:

Construction to begin on fish ladder.
October 1995.

Date:

Draft report to be available on refined minimum flow reco=endations for the
Gunnison River downstream of Redlands Diversion Dam.
January 1996.

Action:

Action:

Final report to be available on refined minimum flow reco=endations for the
Gunnison River downstream of Redlands Diversion Dam.
March 1996.

Date:

Action:
Date:

Fish ladder construction to be complete; operation and evaluation to begin.
April 1996.

Date:

Automatic radiotelemetry system to be deployed (sensors to be installed above,
below and within the fish ladder to monitor movements and distribution of
radio-tagged Colorado squawfish).
June 1996.

Action:

2