WSPC01779

• File Number: 8272
• Description: Colorado River - Colorado River Basin Salinity Control Program - CRBSCP
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 2/1/1989
• Title: Salinity Update - February 1989
• Water Supply Pro - Doc Type: Publication

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OrZ313

THE SOLUTION 4

costs. Agricultural losses (either
through lower yields or higher
production/ management costs)
begin when salinity levels of
applied irrigation water reach 700 to
850 mg/L, depending upon soil
conditions and type of crop grown.

In the late 1960's and early
1970's, leaders at the regional and
national levels began to recognize
the total problem and to seek
comprehensive solutions.

THE SOLUTION

In 1972, an amendment to the
Federal Water Pollution Control
Act, Public Law 92-500 (now known
commonly as the Clean Water Act),
sets forth a public policy embracing
the restoration and maintenance of
water quality, pollution effluent
discharge limitation, and eventual
zero pollution discharge. EP A
interpreted the Act to require water
quality standards, including bene-
ficial use designations, numeric
salinity criteria, and a plan of imple-
mentation for the Colorado River.
Numeric criteria were subsequently
established at three stations by the
Colorado River Basin Salinity
Control Forum (Forum). The
criteria and a plan of implementa-
tion were adopted by each of the
Basin States and approved by EP A.
The criteria, set in terms of
milligrams per liter of TDS, are
shown in the following tabulation.

Location

Annual flow-
weighted average
IDS (m~ IU

Below Hoover Dam 723
Below Parker Dam 747
Below Imperial Dam 879

To meet these criteria, under
future conditions, approximately
1.0 million tons of salt annually will
need to be removed from the river's
waters. The overall strategy in
meeting the standards is to prevent
salt from entering and mixing with
the river's flow. A number of
agricultural, point, and diffuse
sources of salinity have been
identified throughout the Basin.
The salinity control program will
implement controls at those sites
which contain salt sources that can
be intercepted, reduced, and/or
prevented from entering the river at
least cost.

J

In June 1974, Congress enacted
the Colorado River Basin Salinity
Control Act, Public Law 93-320,
which directed the Secretary of the
Interior to proceed with a program
to enhance and protect the quality of
water available in the Colorado
River for use in the United States
and the Republic of Mexico.

Title I of Public Law 93-320
enables the United States to comply
with its obligations under the
agreement with Mexico dated
August 30, 1973 (Minute No. 242 of
the International Boundary and