WSP09806

• File Number: 8273.100
• Description: Colorado River Basin Salinity Control - Federal Agencies - Bureau of Reclamation
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 11/1/1985
• Author: BOR
• Title: 1985 Evaluation of Salinity Control Programs in the Colorado River Basin
• Water Supply Pro - Doc Type: Report/Study

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FINDINGS AND RECOMMENDATIONS

The findings and recommendations that are briefly summarized
here a~e the result of a joint evaluation process conducted
by the Department of the Interior and the Department of
Agricul~ure. The findings are presented as a program manage-
ment tobl to accomplish salinity control objectives at
minimum cost. This approach to long-term, program-wide analy-
sis is ~elpful to Federal program managers when weighing
the man~ budget choices each year.

The 198,5 Evaluation Report was prepared using data adjusted
to more accurately compare the program information of the
two departments. All costs (October 1984) and interest
rates (18 3/4 percent) have been adjusted to the same base.

The base case ,condition for the CRSS model evaluation
assume~ no funds expended on salinity control beyond those
alread~ spent on Grand Valley, Meeker Dome, Uinta Basin, and
Las Veifias Wash. These projects, or portions thereof, have
alreadt, removed approximately 115,600 tons of salt annually
from th~ river system. As measured against the base case,
projec~ions of future salinity used an historical hydrology
(1906-~983) data base in 15 sequences and the Bureau of
Reclam~tion depletion projections (similar to the Forum's
high depletion level).

The TD~ at Imperial Dam is projected to reach about 1005
mg/L by the year 2010. Using the salinity projections at
Imperial Dam, salt load reductions required to reduce pro-
jected ~DS levels to the numeric criteria level of 879 mg/L
were eg\timated and are referred to as the "target."
Because of hydrologic fluctuations in the Colorado River
Basin, ,the target salt load reduction would be met about
50 perdent of the time in the future.

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The budget constraints computer model developed by
Reclam~tion and Colorado State University was used to
evalua~e different project investment levels. This model
determi~es the optimal combination of projects and construc-
tion ti~ing to meet salt load reduction goals at minimum
investment levels. The annual and cumulative construction
costs ~ere constrained by $10 million increments for a total
of $50 million annually and a total cumulative investment
level-~$301 million, $570 million, etc.

Project cost effectiveness ($/ton) was not the determining
factor in the analysis by the model and, while it is impor-
tant in' selecting the projects to implement (as directed in
Public Law 98-569), it is not the only consideration in the

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