A team from the University of Arizona analyzed the water budgets of several Arizona cities to determine how severe the drought impacts would be from the deepest one-year (1900), five-year (1900-19), and ten-year (1946-1955) droughts on record. Case study sites included two of the fastest growing areas in the U.S. -- the Phoenix and Tuscon Active Management Areas (AMAs). In these AMAs, stringent groundwater management is mandated under the 1980 Arizona Groundwater Management Act. The study showed that, even under assumptions of continuing "average" climate conditions, the possibility of achieving "safe yield," as articulated in the Act, (i.e., supply and demand are in balance), remains uncertain. Thus, future severe droughts have the potential to cause significant economic and social impacts, particularly where groundwater pumping is the sole source of supply.

Credit: University of Arizona project