Colorado River Water Dispute (COLORADO Case)

          CASE NUMBER:             17 
          CASE MNEMONIC:           COLORADO
          CASE NAME:               Colorado River Water Dispute  


1.        The Issue

     The 1944 United States-Mexico Treaty for Utilization of  
Waters of the Colorado and Tijuana Rivers and of the Rio Grande  
allots to Mexico a guaranteed annual quantity of water from these 
sources.  The treaty does not provide specifically for water  
quality, but this did not constitute a problem until the late  
1950's.  Rapid economic development and increased agricultural  
water use in the United States spurred degradation of water  
quality received by Mexico.  Much of the increased water is  
intended for producing agricultural products for export.  With a  
view to resolving the problem, Mexico protested and entered into  
bilateral negotiations with the United States.  In 1974, these  
negotiations resulted in an international agreement, interpreting 
the 1944 Treaty, which guaranteed Mexico water of the same  
quality as that being used in the United States.

2.        Description

     Colorado River water quality was not an issue until 1961.   
Until that time Mexico received unused Colorado river flows over  
and above the Treaty requirements, and the quality of the water  
delivered to Mexico was nearly the same as that used in the lower 
Colorado River Basin of the United States.

     In the 1950s, however, several factors contributed to a  
serious decline in water quality.  Intense development in the  
southwest United States and the lure of increased agricultural  
trade resulted in rapidly growing demands for use of Colorado  
River waters.  The United States began diverting significant  
amounts of water from the Colorado River in order to irrigate new 
areas under cultivation.  The Wellton-Mohawk Irrigation and  
Drainage District of Arizona was the most important of these  
projects.  At the same time that excess water became scarce,  
Arizona began pumping highly saline drainage from the Wellton-  
Mohawk project back into the Colorado River.  While the United  
States continued to fulfill the Treaty's water quantity
requirement by returning most of the diverted water to the river  
before it reached Mexico, it chose to overlook the decline in  
water quality.  This was due to the high salinity of water used  
in the irrigation process and pumped drainage.  Ironically, the  
Mexican farmers denied quality water are among the most feared  
competitors of the U.S. agriculture industry.

     In November, 1961 Mexico formally protested that the waters  
it was receiving were not suitable for agricultural uses, and  
that agricultural production in the Mexicali Valley was being  
adversely affected.  Mexico further alleged that the United  
States was violating the 1944 Treaty and international law.  

     In 1972, the United States and Mexico found a "permanent and 
definitive solution" to the salinity problem.  In addition to  
agreeing to provide Mexico with the quantity of water required  
under the 1944 Treaty, the United States said it would meet  
certain standards of average water quality.  To meet this
objective the United States built a desalinization plant in  
Arizona to process the water from the Wellton-Mohawk diversion.   
This process decreased the mineral content of the water before it 
was returned to Mexico via the Colorado River.  The United States 
also constructed, at its expense, a drain to carry the waste  
produced by the plant directly to the Gulf of California,
bypassing the Colorado River completely.  In addition, the United 
States agreed to help Mexico obtain financing for improvements  
and rehabilitation of the Mexicali Valley.

3.        Related Cases

     ISRAELH2 case
     ATATURK case
     ARAL case
     LESOTHO case
     MARSH case

     Keyword Clusters         

     (1): Domain                       = North America [NAMER]
     (2): Bio-geography                = DRY
     (3): Environmental Problem        = WATER

4.        Draft Author:  Julie Ferguson

B.        LEGAL Clusters

5.        Discourse and Status:  AGReement and COMPlete

     In 1965, Mexico and the United States entered into a five-  
year agreement (subsequently extended for two more years) which  
provided for various measures to ameliorate the salinity problem. 
In 1972, President Echeverria of Mexico emphasized to President 
Nixon the importance to Mexico of the water quality problem and  
urged him to engage in a mutual effort to find a more permanent  
solution.  President Nixon established a task force to study the  
problem.  In 1972 the task force submitted its recommendations,  
and the two countries resumed negotiations on the basis of these  
recommendations.  Final implementation of the international  
agreement came in 1974.  

6.        Forum and Scope:  NAFTA and REGION

     Mexico and the United States negotiated an agreement in 1944 
 but it no doubt now relates to NAFTA provisions, and therefore  
possibly impacts Canada.  The current border plan being developed 
by the United States includes questions of water quality covered  
by the 1972 accord.  In the 1960s, Mexico contemplated recourse  
to the International Court of Justice or an ad hoc international  
tribunal.  Both the United States and Mexican representatives  
agreed that a prompt, bilateral, practical, political solution  
would be preferable to the extent that it would save time,  
maintain goodwill and avoid uncertainty.  In the end, the matter  
was referred to the US-Mexican International Boundary Waters  
Commission which undertook scientific studies and provided a  
forum for negotiations.

7.        Decision Breadth:  3 (USA, Canada and Mexico)

8.        Legal Standing:  TREATY

C.        GEOGRAPHIC Clusters

9.        Geographic Locations

     a.   Geographic Domain : North America [NAMER]
     b.   Geographic Site   : Western Northern America [WNAMER]   
     c.   Geographic Impact : USA

     The highly saline water affects an area spanning the
Colorado River Basin states, the Tijuana and Rio Grande Rivers  
and the Gulf of California.  

10.       Sub-National Factors:  YES

     All of the states in the U.S. southwest have a stake in the  
water availability from the Colorado River, or tributaries to it. 
At minimum, this includes California, Arizona, Nevada, Colorado,
and Utah.  Colorado River tributary areas include states as far  
away as Wyoming and New Mexico.

11.       Type of Habitat:  DRY

D.        TRADE Clusters

12.       Type of Measure:  Regulatory Standard [REGSTD] 

     The final agreement with Mexico was rendered in the form of  
Minute Number 242 of the International Boundary and Water
Commission.  This minute interpreted the 1944 Water Treaty.  It  
was an international agreement, but not itself a treaty, and in  
consequence did not require ratification by either side.  Its  
implementation, however, was dependent on U.S. congressional  
authorization of funds.

13.       Direct vs. Indirect Impacts:  INDirect

14.       Relation of Measure to Environmental Impact
     a.   Directly Related to Product   : YES  AGRICulture
     b.   Indirectly Related to Product : NO
     c.   Not Related to Product        : NO
     d.   Related to Process            : YES  WATER

15.       Trade Product Identification:  WATER

     The 1944 United States-Mexico Treaty allots Mexico a
guaranteed annual quantity of 1,500,000 acre feet of Colorado  
River flows.

16.       Economic Data

17.       Impact of Measure on Trade Competitiveness:  NA

     The resultant international agreement between Mexico and the 
 United States resulted in substantial cost to the United States  
in the amount (estimated) of $280,000,000: for (1) desalting of  
the Wellton-Mohawk Drainage Project; (2) extension of a lined  
bypass drain to carry Wellton-Mohawk drainage and brine from the  
desalting plant to the Santa Clara slough on the Gulf of
California; and (3) financing Mexico's improvements and
rehabilitation of the Mexicali Valley.

18.       Industry Sector:  AGRICultural

19.       Exporter and Importer:  USA and MEXICO

E.        ENVIRONMENT Clusters

20.       Environmental Problem Type:  Pollution Sea [POLS]  

21.       Name, Type, and Diversity of Species 

          Name:          Many
          Type:          Many
          Diversity:     NA

22.       Impact and Effect:  HIGH and PRODuct

     As mentioned above, the quality of the water delivered to  
Mexico was adequate until 1961.  In 1961, the combination of  
highly saline drainage from the Wellton-Mohawk Irrigation and  
Drainage District of Arizona and a decrease in availability of  
excess waters began to take its toll in the Mexicali Valley,  
Mexico.  The effect of these two conditions was to increase the  
average annual salinity of waters made available to Mexico from  
an annual average of 800 parts of salt per million to nearly  
1,500 parts per million. 

     Pending a permanent solution to the problem, the United  
States engaged in selective pumping of the Wellton-Mohawk
drainage wells to alleviate salinity at certain times and
constructed a channel to bypass the drainage to the Gulf of  
California.  The United States also released approximately 50,000 
feet annually of stored water to meet the Mexican entitlement of 
1.5 million acre-feet.  By 1971, these measures had reduced the  
average annual salinity of waters to Mexico to 1,245 parts per  

     The Task Force investigated more permanent solutions
revealed three possibilities: (1) elimination of the source of  
higher salinity; (2) substitution of quality water from storage  
for the Wellton-Mohawk drainage; or (3) desalting the Wellton-  
Mohawk drainage.  Desalting proved to be the preferred solution.  
Despite being the most expensive solution, desalting had the  
advantage of minimizing loss of water, barriers to development  
and environmental problems.  Additionally, it encouraged
important progress in desalting technology.

     This solution called for construction of a "membrane process 
 desalting plant with at least 70 percent recovery capability of  
about 240 parts per million quality water."  There were hopes  
that the recovery capability of the desalting plant could be as  
high as 90 percent and that continued cooperation between the  
U.S. Government and the Wellton-Mohawk District would lead to an  
increase in water use efficiency.  

     Several options as to how to dispose of the brine resulting  
from desalting operations exist.  These included (1) evaporation  
ponds, (2) discharge through a lined drain to the Santa Clara  
slough on the Gulf of California, and (3) deep well injection.   
The parties settled on the lined channel to the Santa Clara  
slough, because they were found to be less expensive than
evaporation ponds and it was unclear whether deep well injection  
 was feasible.  

23.       Urgency and Impact:  MEDium and 100s of years

     Mexico has serious concerns over the impact of highly saline 
water on farm production in the Mexicali Valley.  

24.       Substitutes:  Bio-degradable [BIODG] products 

VI.       OTHER Factors

25.       Culture:  NO

26.       Trans-Border: YES

     This is essentially a trans-border problem because Colorado  
River water crosses an international border.  Water from the  
river had continuously flowed into the Gulf of California until  
1956, when U.S. agricultural use led to no water discharges to  
the gulf in some summer months.

27.       Rights:  NO

28.       Relevant Literature

Brownell, H. and Eaton S.  "The Colorado River Salinity Problem   
    with Mexico."  American Journal of International Law
    69/255 (1975).

U.S. Congress.  Congressional Record 120.  S-10371 (daily ed.,    
   June 12, 1974). 

Hearings on H.R. 12165 and Related Bills before the Subcommittee  
     on Water and Power Resources of the House Committee on
     Interior.  91st Congress, 1st Session 75 (1973).

Interior Department Document released by the Bureau of 
     Reclamation entitled Colorado River Water Quality
     Improvement Program  (February 1972).

"Symposium on the Salinity of the Colorado River." Natural
     Resources Journal 15/1 (1975).

88 Statute. 266, Pub. L. 93-320 (1974 bill passed by both Houses  
     of Congress, signed into law by President Nixon).

Timm, C. U.S. Department of State Bulletin, 10 (1944): 288-92.   

U.S. Department of State Bulletin 69/388 (September 24, 1973).   

United States-Mexico Treaty for Utilization of Waters of the      
     Colorado and Tijuana Rivers and of the Rio Grande,
     (February 3, 1944, 59 Stat. 1219, T.S. 994 3 U.N.T.S.

Weinberg,  "Salt Talks: United States and Mexican Style:  A Case  
     Study of the Lower Colorado River Salinity Dispute."
     In R. Sein, ed., International Responsibility for
     Environmental Protection (1976). 

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