WSP05261

• File Number: 8271.200
• Description: Colorado River Basin Salinity Control Program - Development and History
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 4/12/1974
• Title: The Colorado River Basin Salinity Control Act - Western States Water Council - April 12 1974 -
• Water Supply Pro - Doc Type: Report/Study

Western States Water Council
Meeting

BOise, Idaho
April 12, 1974

~~~{~~[i

N
N
1'0
01

The WeNton-Mohawk Project, a system of diversion and
distribution works for the irrigation of 75,000 acres along the
Gila River near its confluence with the Colorado, was authorized
by the Congress in 1947, and completed by the Bureau of
Reclamation in 1952. Drainage problems soon developed and
the Project was augmented to include a system of drainage wells
and collection system discharging into the Gila River near its
junction with the Colorado. The drainage system went into operation
late in 1961, discharging approximately 300 second feet of waters
averaging about 6,000 ppm of total dissolved solids into the

Colorado River below the last point of diversion in the United
States, but above Morelos Dam, the Mexican point of diversion
for most of the water delivered under the Mexican Treaty of 1944.
The average annual salinity of the waters received by Mexico
increased from about 850 ppm to nearly 1500 ppm. This marked
increase in salinity of deliveries provoked the filing of a formal
protest with the State Department by the Mexican government.

Of the 1,500,000 acre-feet annually guaranteed to Mexico under
the 1944 Treaty, more than 500,000 acre-feet is derived from
drainage or return flows below Imperial' Dam. Of this arr,ount
the Well ton-Mohawk Project contributes about 220,000 acre-feet
and the balance comes from return flows from other United States
projects.

Early in 1962, at the request of the State Department, the
governors of the seven Colorado River Basin States established
the Committee of Fourteen to advise the State Department and the
International Boundary and Water Commission concerning negotia-
tions with Mexido on the salinity problem.

Interim measures, involving improvement in operation of the
Colorado River and the drainage system in the Wellton-Mohawk
District, were taken in the United States to mitigate .the effects of
the Wellton-Mohawk drainage and negotiations for a more permanent
solution were init iated. In March of 1965 pursuant to a joint
communique of President Kennedy and President Lopez Mateos
"to reach a permanent and effective solution" the two governments
approved Minute 218. This new agreement provided for further

.,

;,

A-3

,
,
.'