Published online by Cambridge University Press: 26 January 2015
The Rio Grande has headwaters in Colorado, flows through New Mexico, and serves as the United States-Mexico border in Texas, emptying into the Gulf of Mexico. Snow melt in Colorado and northern New Mexico constitutes the water river supply for New Mexico and the El Paso region, whereas summer monsoonal flow from the Rio Conchos in Mexico and tributaries, including the Pecos River, provides the Rio Grande flow for southern Texas. The region is mostly semiarid with frequent long-term drought periods but is also characterized by a substantial irrigated agriculture sector and a rapidly growing population. International treaties and interstate compacts provide the rules for allocation of Rio Grande waters between the United States and Mexico and among Colorado, New Mexico, and Texas. Water rights in Texas have been adjudicated, but the adjudication process was based on a wet period; hence, contemporary Rio Grande water rights are overallocated. Issues related to the waters of the Rio Grande include frequent drought, increased municipal demand caused by a rapidly increasing population, supply variability, underdeliveries from Mexico, increasing salinity, inefficient delivery systems, health issues of the population, no economic/financial incentives for farmers to conserve, and water is not typically priced for efficiency. Stakeholders are interested in identifying solutions to limited water supplies while there is increasing demand. There are several activities in place addressing Rio Grande-related water needs, including enhancing delivery distribution efficiency of raw water, conversion of rights from agriculture to urban, improving both agricultural irrigation field distribution and urban use efficiency, developments in desalination, and litigation. None of the solutions are easy or inexpensive, but there are encouraging cooperative attitudes between stakeholders.