The 1980 Groundwater Management Act includes provisions to help prevent this scenario. Under the Act, there are two kinds of areas in which groundwater is regulated:

1. Irrigation Non-Expansion Areas (INAs) – wells larger than small residential wells are metered, and their groundwater use is reported annually. In addition, there is a prohibition on new irrigated agriculture (defined as two or more acres). 
2. Active Management Areas (AMAs) – metering and reporting of groundwater use; prohibition on new irrigated agriculture; developments of six or more homes cannot be platted without proof of a 100-year supply of water that is physically, financially, and legally available. Every ten years, ADWR develops a new management plan for each AMA, with increasingly rigorous conservation and efficiency requirements for all sectors. Agriculture tends to be the biggest water-using sector, and since 1980, new irrigated agriculture has been prohibited within the AMAs and Irrigation Non-Expansion Areas. (No such prohibition is in place outside the AMAs and INAs, which is why some parts of the state have seen an influx of industrial-scale, groundwater-dependent agriculture.) Farms with grandfathered wells are permitted to pump groundwater to irrigate their crops. Energy costs to pump groundwater are a consideration for farmers, particularly as the water table falls and more energy is required to pump it for use. At some point, the energy costs may render some types of irrigated agriculture unprofitable.

Usually, if municipal water is available it is much less expensive and far more reliable than water from an individual private well. Outside AMAs and INAs, there is virtually no regulation on the amount of water a well owner can pump.

Central Arizona municipal water providers will continue to adapt to ensure sufficient and resilient water supplies. Past successes include significant reductions in the use of water per capita through conservation, the extensive use of reclaimed water, the development of diverse water portfolios that include Colorado River water and local Salt and Verde River watersheds, the banking of Colorado River and reclaimed water underground in local aquifers and collaborative regional planning that includes leases and exchanges of both water and infrastructure. 

Additional adaptations may include enhanced conservation, land-use planning that includes incentivizing development on lands with better access to renewable surface water supplies, new and innovative regional partnerships to exchange and lease water and leverage infrastructure between municipal water providers, new infrastructure to treat and deliver wastewater as drinking water, increasing the capacities of local reservoirs, transferring high-priority Colorado River water into Central Arizona via purchase or lease and importation of new water supplies such as desalinated ocean water or brackish groundwater.

Outside of Central Arizona, groundwater, surface water, brackish groundwater desalination, and ocean desalination projects are being implemented. These include the Yuma Desalting Plant, the North Central Arizona Pipeline, and the Binational Desalination Plant located in the Sea of Cortez. Learn more.

Surface water is water found on the surface of the earth. Arizona gets its surface water primarily from the Colorado River and the local Salt and Verde River watersheds, though there are surface waters found in rivers, creeks, and lakes throughout the state.