Water Rights
All water within Arizona belongs to the state, but people can own the right to use water. The main types of water rights are surface water and groundwater rights. Each is governed by different laws. Arizona law has been slow to recognize that surface water and groundwater are hydrologically connected (see Groundwater).
Surface water is all water in streams, rivers, lakes, and ponds, as well as flood waters and water flowing in underground channels. A person who first puts surface water to beneficial use acquires a prior appropriation right to continue using that amount of water. In times of shortage, users with older water rights should get water, while more junior appropriators go without, but enforcement is difficult.
Surface water rights may be forfeited if they are unused for five years or put to non-beneficial use. In-stream uses of water to support recreation, fish and wildlife have been recognized as beneficial since 1976.
Federal and tribal lands, which comprise 70 percent of the state, have federal reserved water rights (see inset map). Many of these potentially enormous senior rights have yet to be quantified.
Groundwater is all water under the surface not flowing in underground streams. Historically, the right to use groundwater belonged to whomever owned the overlying land. Because wells often draw water from beneath neighboring lands and can pump aquifers dry, conflicts often arise. The 1980 Groundwater Management Act established the Department of Water Resources which regulates groundwater use in the Phoenix, Pinal, Prescott, Santa Cruz, and Tucson Active Management Areas (AMAs), where groundwater levels were dropping. In these areas, existing pumpers were granted rights to continue pumping, but severe restrictions were put on large new wells.
Issues Summary