Water allocation and management along the Santa Cruz border region

Water management along the transboundary Santa Cruz River basin overlapping Arizona and Mexico, faces a host of physical, economic and institutional challenges. The situation is worsened by a failure of bilateral strategies to achieve an administratively feasible solution to these problems. The current study, utilizing data from the Santa Cruz Active Management Area in Arizona and from Nogales in Sonora, Mexico, builds an integrated framework of intersectoral water allocation within each region, incorporating relevant economic, physical and institutional constraints. Results from the baseline model and from three scenarios representing population growth and water scarcity, suggest higher optimal water use and net benefits in the urban residential sector for both regions. The outcomes conform to previous studies emphasizing the need for better water supply infrastructure and reuse of treated wastewater to counter demand from a growing population and climate induced water shortages in the region.