WSP06290

• File Number: 8277.600.10
• Description: Big Sandy River Unit - Colorado River Salinity Control Program
• State: WY
• Basin: Colorado Mainstem
• Date: 5/1/1986
• Title: U.S.D.A. Selected Plan - Big Sandy River
• Water Supply Pro - Doc Type: Definite Plan Report

I
I
I

I

Pump testing of those wells above the Eden Project indicate only
minor contributions from that area leading to the conclusion that at
least 75 percent of the recharge to the saline aquifers comes from the
irrigated area, The continuing well monitoring will enable further
refinement of such estimates.

I

I

The bulk of the aquifer discharge occurs along a IS-mile reach of
the Big Sandy River in the form of seeps, springs, and flowing wells.
Investigations indicate that approximately 27 cfs surfaces and flows
back into the river along this reach. The Bureau of Reclamation has
drilled three 15-inch-diameter wells near the larger seeps in the "Big
Bend" area between Simpson Gulch and Gasson Bridge. These wells were
tested with 5-day pump tests at rates from 825 to 2,700 gallons per
minute. The total dissolved solids concentration varied from 4,000 mg/l
to 5,500 mg/l. The flow in the seep area was dramatically reduced
during the pump tests. Results of these pump tests indicated that large
diameter, high producing wells could be used to intercept saline
intrusions along the river; however, disposal of the saline water
remains a major hurdle to a satisfactory salinity control for this type
of project. In 1982, the Bureau of Reclamation evaluated the delivery
of saline underground water from the Big Sandy area to Chevron Chemical
Company and Texasgulf Chemicals, Inc., near the towns of Rock Springs
and Green River. However, both of these companies' plans indicated that
the use of Big Sandy water was not needed. During 1984 and 1985, the
Bureau of Reclamation investigated the use of saline Big Sandy water for
the Jim Bridger Power Plant. This alternative was found to be
economically unattractive because of the long and expensive delivery
system required to transport the water to the Jim Bridger Power Plant.

I

I

I

I

I

I

The Bureau of Reclamation is presently working on a canal and
lateral seepage loss investigation. If seepage investigations indicate
substantial water losses, a technical and economic feasibility of a
selective lining alternative will be evaluated,

I

In 1974, an atmospheric freezing experiment was attempted to
separate fresh water and brine. The experiment encountered problems
with maintaining equipment operating under freezing conditions,
separating the brine flow, evaporation of brine, and most importantly,
pointed out the need for lined collection ponds.

I

I

USDA's Agricultural Stabilization and Conservation Service
administers the Agricultural Conservation Program, which provides
limited cost-sharing funds for the installation of needed conservation
practices, including irrigation improvement measures.

I

I

Science and Education Administration -- Agriculture research is
able to provide assistance to the project area through data collected
from other salinity project areas. This research will give Eden Valley
Irrigation and Drainage District tested and proven irrigation water
management practices which will improve irrigation efficiency and reduce
downstream salinity.

I

II

The local conservation district program provides to the irrigation
district and local landowners technical assistance for irrigation water
management practices. ' r (", ,"'
()"J \. "I <.J...1

I

1-5