WSP11231

• File Number: 8276.130
• Description: Grand Valley Unit-Colorado River Basin Salinity Control Project
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 10/1/1990
• Title: Finding of No Significant Impact for Price Ditch and Stubb Ditch Improvements
• Water Supply Pro - Doc Type: EIS

'.. '"

(>:>
(.:..1
..'J

"""".1

c;)

.

.

Background

In accordance with the National Environmental Policy Act of 1969, as amended,
and the Council on Environmental Quality's Regulations for Implementing the
Procedural provisions of the National Environmental policy Act (40 CFR
Part 1500-1508), the Bureau of Reclamation (Reclamation) has determined that
an Environmental Impact Statement is not required for the inclusion of the
Price Ditch and Stubb Ditch improvements in the Grand Valley unit (Unit) nor
for the deletion of described cross-drainage features from the Unit.

The Unit, which is designed to reduce salt loading to the Colorado River, is
located in Mesa County, Colorado. This Finding of No Significant Impact
(FaNSI) evaluates the environmental impacts and their significance of
improving the Price and Stubb Ditches as part of the Unit and with changes in
cross-drainage plans for previously approved portions of the Unit.

Planned Actions

The recommended plan consists of lining or pipe placement on 7.9 miles of the
10-mile-long Stubb Ditch and 6.9 miles of improved lining on the 9-mile-long
Price Ditch. Measures, including habitat acquisition and improvement and
development of wildlife watering sites, are included to compensate for
wildlife habitat losses that would result from improvement of the ditches.
Cross-drainage facilities, consisting of two flow detention ponds and
6.5 miles of detention ditches, that were previously planned for the Unit
would not be constructed.

Summary of Impacts

1. The privately held water rights would not be changed and water
supplies to the Price and Stubb Ditches would not be decreased.

2. Salt loading to the Colorado River would decrease by 11,500 tons per
year. Seepage from the two ditches would be reduced by 1,615 acre-feet
annually.

3. Natural vegetation along the Price and Stubb Ditches, including
approximately 1 acre of willows, 1.5 acres of cottonwoods, 0.5 acres of
tamarisk, and 3 to 4 acres of rabbitbrush and greasewood, would be lost. In
addition, a maximum of 65 mature cottonwood trees could be lost. To reduce
these losses or compensate for them in accordance with Fish and Wildlife
Service recommendations, the ongoing habitat replacement plan along the
Colorado River for the unit would be increased by 27 acres, and construction
specifications would be written to reduce the loss of cottonwood trees.

4. The Stubb Ditch would be lost or reduced in usefulness as a water
source for wildlife. Four guzzlers (watering sites) would be established
north of the ditch to replace this use.

5. Visual impacts would occur with the clearing of vegetation and the
reduction of open water. This impact would be reduced, but not eliminated,
by efforts to protect cottonwood trees, to recontour disturbed sites, and to
revegetate disturbed areas.