Rock County, Wisconsin — public water systems

How does Rock County compare with other Wisconsin counties?

Rock County has the 31st-most active public water systems among the 90 counties listed for active Wisconsin systems in EPA records; among the 74 with 3 or more systems, the median has 140. Its systems report 148,563 people served in total, the 7th-largest county figure in the state and 2.9% of the statewide total. The average system here reports serving 952 people, about twice the Wisconsin average of 469. 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 Rock County's drinking water come from?

By primary water source, Rock County's active systems draw on groundwater (155, 99%) and purchased groundwater (1, 0.6%). Overall, all rely mainly on groundwater (including purchased groundwater) and none on surface water, compared with 99% and 0.6% across Wisconsin. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, Janesville Water Utility, draws primarily on groundwater.

What kinds of water systems operate in Rock County?

Rock County's active systems break down as 20 community systems (13%), 17 non-transient non-community systems (11%) and 119 transient non-community systems (76%). 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 (81%), local government (17%) and state government (1.9%).