When determining borders, a river is often the clearest delineation between sovereign nations. But that clarity abruptly ends when countries must decide how to use the water that the river provides. Even managing rivers that do not determine borders, but rather travel through multiple countries, is precarious at best. The Rio Grande, which partly establishes the U.S.-Mexico border, is no exception. It has been and will continue to be vital to economic growth in the region, especially in Mexico, where the river and its tributaries are crucial to supporting new opportunities for manufacturing and energy. But growing demands and environmental pressures will increase tension between the United States and Mexico over water resources in the coming decades....
