LegiStorm

Summary:

The United States and Mexico share the Colorado River and Rio Grande pursuant to binational agreements. Increasing water demands and reduced supplies deriving from drought and high heat increase the challenges and significance of treaty compliance. The International Boundary and Water Commission (IBWC), a binational entity with a U.S. Section that operates under the foreign policy guidance from the U.S. Department of State, is charged with addressing issues that arise during application of these treaties. Colorado River. The Colorado River flows through seven U.S. states before reaching Mexico; 97% of the basin is in the United States. A 1944 Water Treaty requires that the United States annually provide Mexico with 1.5 million acre-feet (AF) of Colorado River water, which represents about 10% of the river's average flow. Binational disputes have arisen over water quantity, quality, and conservation. Under the Treaty, disputes can be resolved through amendments, called "minutes." Minute 242 from 1973 requires that salinity of Colorado River water deliveries not exceed a specified limit. Minute 319 from 2012 provides for a bilateral basin water management, storage, and environmental enhancement effort; the minute is to be enforced through 2017 with the possibility of an extension. Rio Grande. The Rio Grande is governed by two separate agreements. Deliveries to Mexico in the northwestern portion of the shared basin (near El Paso/Ciudad Juárez) occur under a 1906 Convention, while deliveries for the southeastern portion (which is below Fort Quitman, Texas) are laid out in the 1944 Water Treaty. The 1906 Convention requires an annual delivery to Mexico of 60,000 AF, which can be proportionally reduced based on drought conditions. The United States is not required to make up for reductions. From 1939 to 2013, deliveries to Mexico were reduced in roughly 30% of the years, including significant reductions in each year since 2012. Under the 1944 Water Treaty, Mexico has rights to two-thirds of the flows of six Mexican Rio Grande tributaries. The one-third delivered to the United States must average at least 350,000 AF per year, measured in five-year cycles. A five-year cycle ended in October 2015, with Mexico likely ending behind on deliveries. Mexico's deliveries fell behind early in that cycle. It is anticipated that the final accounting (which may be available in early 2016) may indicate that Mexico met its deliveries in the cycle's fourth year and was close to meeting the delivery target in the fifth year. Roughly 100,000 AF of the water delivered in the fifth year came from sources not formally covered by the 1944 Water Treaty. Legislative and Diplomatic Responses. Some Members of Congress have expressed concerns about the adequacy of Mexico's 1944 Water Treaty compliance, U.S. efforts to hold Mexico to its treaty obligations, and the resulting economic impacts, especially in Texas border counties. On December 16, 2014, P.L. 113-235, the Consolidated and Further Continuing Appropriations Act, 2015, became law, and a provision in this omnibus legislation required the U.S. Section of the IBWC to report to the Committees on Appropriations on various water delivery and accounting issues within 45 days of enactment. In 2014 and 2015, the U.S. Department of State submitted reports to Congress on the status of Mexico's deliveries, including a status update in September 2015. Also in 2015, the U.S. Department of State raised water issues in meetings with Mexican officials and the IBWC organized a July 2015 meeting in Texas with representatives from the state of Texas and Mexico's national water agency. The Texas meeting's discussion covered basin water modeling efforts and various means to improve the predictability and compliance of Mexico's water deliveries.