Washtenaw County, Michigan — public water systems

How does Washtenaw County compare with other Michigan counties?

Washtenaw County has the 6th-most active public water systems among the 131 counties listed for active Michigan systems in EPA records; among the 88 with 3 or more systems, the median has 92. Its systems report 300,406 people served in total, the 6th-largest county figure in the state and 3.3% of the statewide total. The average system here reports serving 1,147 people, about 35% above the Michigan average of 847. 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 Washtenaw County's drinking water come from?

By primary water source, Washtenaw County's active systems draw on groundwater (254, 97%), purchased surface water (7, 2.7%) and surface water (1, 0.4%). Overall, 97% rely mainly on groundwater (including purchased groundwater) and 3.1% on surface water, compared with 97% and 3.1% across Michigan. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, Ann Arbor, draws primarily on surface water.

What kinds of water systems operate in Washtenaw County?

Washtenaw County's active systems break down as 31 community systems (12%), 45 non-transient non-community systems (17%) and 186 transient non-community systems (71%). 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 (87%), state government (6.5%) and local government (6.1%).