WSP10224

• File Number: 8270.100
• Description: Colorado River Basin Water Quality/Salinity -- Misc Water Quality
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 1/1/1993
• Author: USDOI
• Title: Quality of Water - Colorado River Basin - Progress Report No. 16 - January 1993
• Water Supply Pro - Doc Type: Report/Study

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The enactment of the Federal Water Pollution
Control Act Amendments of 1972 affected
salinity control in that the legislation was
interpreted by EPA to require numerical
standards for salinity in the Colorado River, In
response, the Basin States founded the Colorado
River Basin Salinity Control Forum (Forum) to
develop water quality standards including
numeric salinity criteria and a basinwide plan of
implementation for salinity control. The Basin
States held public meetings on the proposed
standards as required by the enacting
legislation, The Forum recommended that the
individual Basin States adopt the report, Water
Quality Standards for Salinity Including
Numeric Criteria and Plan of Implementation
for Salinity Control, Colorado River System,
The proposed water quality standard called for
maintenance of flow-weighted average total
dissolved solids (TDS) concentrations of
723 milligrams per liter (mg/L) below Hoover
Dam, 747 mg/L below Parker Dam, and
879 mg/L at Imperial Dam, Included in the plan
of implementation were four salinity control
units and possibly additional units, the
application of effluent limitations, the use of
saline water whenever practicable, and future
studies, The standards are to be reviewed at
3-year intervals. All of the Basin States adopted
the 1975 Forum recommended standards, The
EPA approved the standards,

The Colorado River Basin Salinity Control Act of
1974 (Public Law 93-320) provided the means to
comply with United States obligations to Mexico
which included, as a major feature, a desalting
plant and brine discharge canal, These facilities

LEGAL ASPECTS 3

will enable the United States to deliver water to
Mexico having an average salinity no greater
than 115 parts per million (ppm) +/- 30 ppm
(United States count) over the annual average
salinity of the Colorado River at Imperial Dam,
The act also authorized construction of 4 salinity
control units and the expedited planning of 12
other salinity control projects above Imperial
Dam as part of the basinwide salinity control
plan,

In 1992, the Forum reviewed the salinity
standards and recommended continuing the
construction of units identified in the 1974 Act,
the placing of effluent limitations on industrial
and municipal discharges, and the reduction of
the salt loading effects of irrigation return flows.
The plan also called for the inclusion of water
quality management plans to comply with
section 208 provisions after the adoption of the
plans by the States and approval by EP A, It
also contemplated the use of saline water for
industrial purposes and future salinity use
control methods,

Public Law 98-569, signed October 30, 1984,
amends Public Law 93-320, The amendments to
the Salinity Control Act authorized the entire
U,S, Department of Agriculture (USDA) salinity
control program, The amendments also
authorized two new units for construction under
the Bureau of Reclamation program, Additional
units will need to be authorized to maintain the
salinity standards and have been included in the
plan of implementation for the salinity control
program,