Tucson is located in the semi-arid northern reaches of the Sonoran Desert in southeastern Arizona, with mountains on each side – the Santa Catalinas to the north, the Rincons to the east, the Tucson Mountains to the west, and the Santa Ritas to the south. Most of the population of the greater Tucson area lives between these mountain ranges in the Santa Cruz River Valley. In addition to climatic factors, population growth, and increasing municipal and industrial demand are the most important drivers of water supply in Arizona today (AWI 2008:16) and this is true for Tucson as well. The valley’s dry desert air and winter sunshine make it a popular health and winter resort destination, and the city provides high-tech services such as health care facilities for the region, an optics research center, the University of Arizona, and industrial production focused on the defense sector. Urban Tucson and much of surrounding Pima County depend largely on the Colorado River, plus groundwater, for meeting their water needs.
Keywords: climate change; water resources; Tucson basin; Tucson Water; drought; water banking; scenario planning