Maricopa County, Arizona — public water systems

How does Maricopa County compare with other Arizona counties?

Maricopa County has the 2nd-most active public water systems among the 56 counties listed for active Arizona systems in EPA records; among the 19 with 3 or more systems, the median has 63. Its systems report 4,419,761 people served in total, the largest county figure in the state and 57% of the statewide total. The average system here reports serving 20,368 people, about 4.7 times the Arizona average of 4,369. Population figures are what each system reports; people served by more than one system, such as a wholesaler and the town that buys from it, are counted by each.

Where does Maricopa County's drinking water come from?

By primary water source, Maricopa County's active systems draw on groundwater (190, 88%), surface water (16, 7.4%), purchased surface water (10, 4.6%) and purchased groundwater (1, 0.5%). Overall, 88% rely mainly on groundwater (including purchased groundwater) and 12% on surface water, compared with 95% and 4.7% across Arizona. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, City of Phoenix, draws primarily on surface water.

What kinds of water systems operate in Maricopa County?

Maricopa County's active systems break down as 100 community systems (46%), 45 non-transient non-community systems (21%) and 72 transient non-community systems (33%). A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. EPA lists their owner types as private (41%), public/private partnership (34%), local government (18%) and federal government (4.1%).