PROBLEM OF COLORADO RIVER SALINITY
The basic document: the 1944 US-Mexico Treaty. It provides that we will supply annually to Mexico 1.5 million acre-feet of usable water from the Colorado River.
The salinity problem dates from 1961 when the salt content in Colorado water rose to a high level because of the Wellton-Mohawk drainage project in Arizona.
In 1965, we concluded a five-year Agreement with Mexico. It dealt with the salinity problem mainly by replacing 50,000 acre-feet of Wellton-Mohawk water with the same amount of low-saline water from Yuma-Mesa. The Mexicans also agreed to bypass (i.e., not use) 50,000 acre-feet of high-saline water.
In 1970, the agreement came up for renewal. We offered to double the quantity of Yuma-Mesa “clean” water, thus raising the quality of water going to Mexico. The deal was acceptable to Diaz Ordaz but he decided to leave the problem to the incoming Administration of Luis Echeverria.
The latter’s counter-proposal was that we replace the full 220,000 acre-feet of high-saline water from Wellton-Mohawk with purer Yuma-Mesa water. This raised serious technical problems. The experts estimated the necessary new wells, pumps and enlargement of the conveyer channel would cost between $10 million and $20 million. Even more serious, it would have lowered the water table and reduced Arizona’s water reserves by 120,000 acre-feet per year. This idea met with a buzzsaw of opposition from the Hill (especially from Goldwater, Fannin, and company). It was judged impossible to get Congress to provide the $10–$20 million that would be necessary to meet Mexican demands.
This impasse produced agreement to extend the 1965 arrangement for one year. Negotiations in 1971 were equally fruitless and produced another one-year extension.[Page 2]
1) Quality of water—US users along the Colorado are apparently getting water with about 850 parts per million (ppm) of salt. Mexican users complain their level is about 1,250 ppm. Mexico wants to sharply reduce that difference. They blame the low quality of the water they are getting primarily on the introduction of Wellton-Mohawk drainage water into the Colorado.
2) What is usable water? Mexicans claim that the high-saline water they are getting is not “usable” for their needs. Our experts at Agriculture insist the water is usable for the soil and products common to the Mexicali valley.
3) Costs—We can get the $400,000–$600,000 needed to improve Colorado water to the levels we are ready to promise. We can not get the $10–$20 million required to meet maximum Mexican demands. (I would guess there is some flexibility between these two extremes, but only our Congressional specialists probably know.)
4) Domestic politics—The seven Colorado basin states have a keen interest in this, especially Arizona and California. Their concerns: costs and endangering the water reserves. On the other hand, they appear willing to make some concessions in the interest of a settlement. There is some concern that if the Mexicans get angry enough and force some kind of international adjudication, we may get a worse settlement than through direct dealings with Echeverria and Rabasa.
5) Legal Issues—Central here is the question of what is “usable water“. Mexicans have repeatedly threatened to“take us to court”. Their view of arbitration is the kind provided in the 1929 Havana Convention—i.e., four Latin Americans and one US representative, a stacked deck. Our preference is the International Court of Justice, though we are concerned that the ICJ might try to “rewrite the treaty”. In any case, we would like to avoid outside mediation or arbitration if at all possible. Litigation would take a long time, probably years. Tensions between the two countries would be strained during the period. The “loser” would be bitter. It would set a bad precedent in relations with Mexico, as well as our dealings with the rest of the Hemisphere.[Page 3]
CURRENT STATE OF PLAY
We were close to settlement in November 1971 on a new Six-Year Agreement when the Mexicans suddenly broke off. We had offered a schedule of using “substitute waters” that would have provided Mexico with the agreed quantity of water at a salt-balance of about 1140–1200 ppm. That would have meant using some 554,000 acre-feet of low-saline water over the six years. We also suggested legal talks on rights and obligations under the 1944 Treaty. However, we required that Mexico agree not to seek third-party adjudication or mediation during the term of the agreement.
The Mexicans turned us down. They apparently were not satisfied with the extent of improvement in water quality. They were also reluctant to commit themselves to forego appeal to a third party for as long as six years.
Rabasa outlined Mexico’s desires in a letter to Secretary Rogers last September. Our November proposal was designed to meet those demands. Rabasa has since admitted that our November offer came far closer to his position than he realized when he broke off the talks.
State is reported to be readying a new offer to Mexico. We are in a position to offer somewhat better water immediately because salinity of the Colorado did not increase last year nearly as much as the experts expected.
We seem to have three principal options:
1) to offer Mexico good water (as low as 1120 ppm., with the agreement of the Basin states) immediately with some decline in quality over the term of the agreement (presumably five years);
Problem: Mexico would probably find it politically hard to accept the notion of declining water quality.
2) a gradual improvement in water quality over the five-year period (by not offering the best possible water now, but using increasing [Page 4] amounts of better over the five years.)
Problem: If water steadily improves, Mexico will expect that trend to continue after the five years. We would then face the same old problems—increased costs and depletion of our own water reserves.
3) providing water of relatively stable quality over the five years.
Problem: We have consistently avoided guaranteeing a ceiling on the salinity of water provided Mexico. It would be increasingly costly to provide in the future. No US user has such a guarantee. The Basin states would balk because it might eventually mean we were committed to giving Mexico water of higher quality than that going to our own users.
In the above option, we are talking about a salinity level of probably 1180 ppm. The Mexicans can be expected to ask for 1140–1150 ppm.
The latest indication on this, prior to your own talk with Rabasa, was that Rabasa might be inclined to:
1) revert to the salinity figures in the September 1971 proposal (which were extremely close to our own of November) with provision for declining salinity, however gradual;
2) seek interim agreement for three or four years;
3) stick to Mexico’s legal position without demanding our concurrence.
NOTE: The above was compiled without reference to State or the experts. Thus, there may be elements not given full justice. We can go into this in more detail, if you wish. One thing we obviously need to know is the state of mind of the Basin state Congressional representatives—especially re availability of funds, and use of water reserves. I assume that State has a reading on this, especially if, as they claim, they are readying a new proposal.
- Source: National Archives, Nixon Presidential Materials, NSC Files, Box 788, Country Files, Latin America, Mexico, Vol. III, 1972. Confidential. This study is attached to a March 25, 1972, covering memorandum from Jorden to Kissinger. According to an attached note, this study was “Noted by HAK” on March 28.↩
- Jorden prepared a background study for Kissinger on the Colorado River salinity issue, which included a list of policy options.↩