BOARD02231

• Board Meeting Date: 9/24/2001
• Description: WSP Section - Colorado River Basin Issues - Discussion on Future Policy Regarding the Yuma Desalter Plant
• Board Meetings - Doc Type: Memo

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Colorado Water Conservation Board
Department of Natural Resources
1313 Sherman Street, Room 721
Deriver, Colorado 8020,
Phone: [phone]
FAX: [phone]
www.cwcb.state.co.us

STATE OF COLORA.DO

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MEMORANDUM

Bill Owens
Governor
Greg E. Walcher
Executive Director
Rod Kuharich
eWeB Director
Dan McAuliffe
Deputy Director

TO:

Colorado Water Conservation Board Members

FROM:

Randy Seaholm I))\lk
Chief, Water Supply Protection

DATE: September 14, 2001

SUBJECT: Agenda Item 8g, September 24-25, 2001, Board Meeting-
Colorado River Basin Issues -
Discussion on Future Policy Regarding the Yuma Desalter Plant

Backl!round

The 1944 Treaty that guaranteed Mexico 1.5 MAF of Colorado River water
annually "from any and all sources" did not set any water quality or salinity standard,
Irrigation water with high concentrations of salinity is an economic problem because it
reduces crop yields and even precludes the growing of certain salt-sensitive crops,
particularly vegetables like lettuce and tomatoes.
Between 1960 and 1961, the salinity of water delivered to Mexico increased from
800 ppm to in excess of 1300 ppm. There were two primary reasons for this increase,
First, the Wellton-Mohawk Irrigation and Drainage District near Yuma, Arizona began
operation of a pumped drainage system that returned drain water of about 6,000 ppm to
the river. Second, the filling of the Colorado River Storage Project, in particular Glen
Canyon Dam, reduced the flows in the lower Colorado River.
As a result, in November 1961, Mexico filed a formal diplomatic protest,
charging the U.S, with violating intemationallaw, In 1965, the U.S, and Mexico agreed
to several temporary measures for reducing the salinity of Colorado River water under
Minute 218, The search for a "permanent, definitive and just solution" ended with the
signing of Minute 242 on August 30, 1973. Minute 242 guarantees Mexico that the
average annual salinity of its treaty deliveries will be no more than 115 ppm higher than
the salinity of water behind Imperial Dam, plus or minus 30 ppm, Subsequently, the
Colorado River Salinity Control Program that grew out of PL 93-320 established a
salinity standard of 879 ppm for the water arriving at Imperial Dam.
To implement Minute 242, the V.S, Congress passed the Colorado River Basin
Salinity Control Act (CRBSCA or PL 93-320) on June 24, 1974, The CRBSCA has two
parts, Title I-Programs Downstream from Imperial Dam and Title II-Programs Upstream
of Imperial Dam. Title I of the CRBSCA authorized the Secretary of Interior to, among
other things, construct, operate and maintain the Yuma Desalting plant to reduce the
salinity of drain water from the Wellton-Mohawk division of the Gila Project, extend the
bypass drain from the Yuma Desalter and other areas to the Santa Clara Slough, acquire

Flood Protection. Water Project Planning and Financing. Stream and lake Protection
Water Supply Protection. Conservation Planning