International Water Law: The United States and Mexico


Denver, Colorado       April 12, 2013

International Water Law: The United States and Mexico

The second panel discussion of the Symposium focused on the international legal regime governing the allocation of Colorado River water between the United States and Mexico.  Specifically, the panelists focused on the 1944 Mexican-American Treaty (“1944 Treaty”) and the recently enacted Minute 319 to the 1944 Treaty.

The first panelist was Edward Drusina, the United States Commissioner of the International Boundary and Water Commission (IBWC).  The IBWC is the intergovernmental agency charged, under the 1944 Treaty, with application of all the boundary and water treaties between the United States and Mexico.  The IBWC also settles differences in the application of those treaties.  Most importantly, the 1944 Treaty charged the IBWC with administering the rights and obligations of the United States and Mexico regarding the waters of the Colorado River and the Rio Grande.

The Commissioner began by giving a brief overview of the 1944 Treaty, the IBWC, its mission and history. He then gave a narrative overview of the joint cooperative process that culminated in the historic Minute 319, beginning with the 2007 joint statement by the Secretary of the Interior and the Mexican Ambassador.  This joint statement asked the IBWC to begin working towards solutions to the growing problems between Mexico and the United States regarding the boundary waters of the Colorado River Basin.

Minute 317 to the 1944 Treaty, signed in 2010, was the first major cooperative agreement following the 2007 joint statement.  Minute 317 set the framework for the subsequent bilateral talks on the Colorado River Basin by formalizing international workgroups and noting topics for further study.

Unfortunately, the 2010 earthquake in the Mexicali Valley destroyed large sections of the water diversion infrastructure in the Valley and the surrounding area.  Without emergency action on both sides, large amounts of Mexico’s Colorado River allotment would have been lost. The parties reached an innovative and unprecedented solution allowing Mexico to store almost 230,000 acre-feet of its total 1.5 million acre-feet allotment in the United States’ reservoir system.  This allowed Mexico to postpone its Colorado River water deliveries until those responsible could repair the damage from the earthquake.

In order to give Mexico sufficient time to complete repairs, the United States and Mexico entered two years of intense negotiations in order to solidify the arrangement set out in Minute 318 and to begin to deal with other issues facing the Colorado River Basin.  However, because of the nature of the water storage arrangement, Commissioner Drusina and his Mexican counterpart opted for only a five-year extension to Minute 318 in order to make sure the arrangement would work in everyone’s best interest.  Minute 319, signed in 2012, codified this extension to the Minute 318 storage arrangement and included several other provisions dealing with shortage sharing, surplus sharing, salinity concerns, water allocations for environmental programs, and a call for a twenty-one-million dollar investment in Mexico over the five-year cycle of Minute 319.

Following Commissioner Drusina was Karen Kwon, the Colorado Assistant Attorney General.  Kwon gave an overview of the states’ roles in the international management of the Colorado River Basin and ways individual states have an impact on the diplomatic process.  Most importantly, the Colorado River Basin States (“Basin States”) have responsibilities under the 1944 Treaty to help keep the United States in compliance with its obligations to Mexico.  Also, the Basin States have played a major role in furthering coordinated management of the basin.  For example, during the negotiations over Minute 319, the Basin State representatives made sure that the lower basin states did not benefit at the expense of the upper basin states, and vice versa.

The final panelist, Peter Culp, first gave a brief description of how Mexican water rights holders utilize Colorado River water.  The vast majority of Mexico’s allotment of Colorado River water goes to agricultural uses, with the rest diverted mainly for use by municipalities.  According to Culp, nearly three-million people rely on this water supply.  Because the Mexicali region lies downstream from every American farm and municipality in the Basin, salinity and other chemical imbalances are a major problem for water users in northern Mexico.  Minute 319 begins to address this problem.

Culp then laid out the environmental implications of Minute 319 for the Colorado River delta ecosystem.  The delta, at the mouth of the river leading to the Sea of Cortez, plays a vital role in maintaining the health of both the river and its attendant fish and bird species.  Since the turn of the last century, however, the delta shrank dramatically to the point where the delta ecosystem had been declared effectively dead by the 1970s.  A large flood in the early 1980s actually reversed some of the degradation, which in turn spurred efforts to restore the delta.  Though some have made the assertion, Culp was quick to point out that the proponents of these efforts are not attempting to restore the delta to its historic maximum.  Instead, these efforts, which Minute 319 funds in part, will restore only a relatively small, perennial riparian ecosystem within the limits of the historic delta.  In addition to funding restoration efforts, Minute 319 storage arrangements between the United States and Mexico will allow Mexico to store and release water in a manner that will best facilitate restoration of the delta.