WSP09303

• File Number: 8220.106
• Description: Animas-La Plata
• State: CO
• Basin: San Juan/Dolores
• Water Division: 7
• Date: 1/1/1979
• Author: Unknown
• Title: Questions and Answers - Animas-La Plata Project
• Water Supply Pro - Doc Type: Report/Study

M'p.s-LA PLATA PROJECT

Bureau of Reclamation studies have indicated that the river flow
reduction would have no significant adverse impact on game fish. A more signi-
ficant impact might be realized on non-game fish; some sucker species might
be reduced in number by 10 percent.
River floating opportunities would be adversely impacted to some degree;
a loss of 44 days annually has been estimated by Bureau of Reclamation studies.
Water quality in the river would not be significantly affected by the
project. On the short term, sediment concentrations and turbidity would in-
crease due to construction. Long term effects would include increases in
temperature, nutrient levels, and salinity.

2. WHAT IS TO BE THE MINIMUM FLOW I~ THE ANIMAS? How DOES THAT COMPARE TO
THE RIVER FLOW AS WE KNOW IT ~OW. Water would not be pumped from the
Animas R1VAr at Durango by the proJect if the flow of the river is at or be-
low 225 cubic feet per second (cfs) during April through September or 125 cfs
during October through March. The minimum flow at Durango in 1977 was l29cfs.
The average minimum flow during the past 20 years was 155 cfs.

3. WHAT ARE THE PRESENT WATER QUALITY STANDARDS REGARDING SALINITY? WHAT
PLANS ARE BEING MADE TO CONTROL SALINITY? In reformulating the project
plan highly saline lands were left out and sprinkler irrigation was introduced.
This resulted in more than a ten fold reduction in salt contribution to the
Colorado River system over that contained in the authorizing report.
The U.S. Public Health Service has a drinking water standard for salinity
of 500 milligrams per liter (mg/L). The average salinity of the Animas River
at Durango is 290 mg/L. The project would not significantly change the salin-
ity of the Animas River between Durango and Farmington. The average salinity
of the La Plata River at Farmington would be increased from 845 to 2,530 mg/L.
The project would increase the salinity of the San Juan River at Bluff, Utah
from 470 to 520 mg/L.
Salinity standards in the lower basin have been adopted by the 7 Colorado
River Basin states and the Environmental Protection Agency. The establish-
ment of these standards is a part of a basinwide program of salinity control
being undertaken to maintain salinity at or below present levels while the
basin states continue to develop their compact apportioned water.
The salinity of the Colorado River at Imperial Darn will be increased by
17.3 mg/L as a result of this project. Of this 17.3 mg/L increase, 12 mg/L
would be from salt loading and 16.1 mg/L from stream depletion.
Public Law 93-320, the Colorado River Basin Salinity Control Act, passed
June 24, 1974, authorized construction of 4 salinity control units and study
of additional units. Installation of all units would reduce the concentration
at Imperial Dam by an estimated 171 mg/L by the year 2000. These units would
negate the salinity effects of the Animas-La Plata Project. In addition,
conservation measures, including those related to water quality, are required
by provisions of the repayment contract for the project.

4. WHAT WILL HAPP~N TO WATER REC8E~TION A~D FISH~NG ~ELOW THE POINT OF
DIVERSION? F1sh1ng opportun1t1es wou d not e s1gnificantly affected
by pumping from the Animas River. The only fish that would be reduced in num-
bers would be some species of suckers, which might suffer a reduction of 10
percent in number.
River floating would be adversely affected, with an annual loss of 44 days
estimated by the Bureau of Reclamation.

5. WHAT KINDS OF CONTROLS WILL THERE BE AROUND THE LAKE ITSELF AS f~R AS
DEVELOPMENT IS CONCERNED? CABI~S - BOAT DOCKS - CO~MERCIAL? A lands
adjacent to Ridges Basin Reservoir w1ll be owned and adm1nistered by the
Bureau of Reclamation. Development of the reservoir area would be aimed at
not competing "with business facilities already provided by the private sector."
Planned Facilities for public use include a seven lane boat ramp and 34
place boat mooring area. Also planned are a 54 place camping area, 48 unit
picnicking area and 10 miles of hiking trails. Overnight accommodations are
planned to be basic facilities only (toilets, tables and firepitl.
The only concessionaire that has been looked at is a marina operation for
boat rentals and similar related items.

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