Columbia County, Washington — public water systems

How does Columbia County compare with other Washington counties?

Columbia County has the 36th-most active public water systems among the 72 counties listed for active Washington systems in EPA records; among the 44 with 3 or more systems, the median has 75. Its systems report 4,729 people served in total, the 37th-largest county figure in the state and less than 0.1% of the statewide total. The average system here reports serving 364 people, well below the Washington average of 2,172. 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 Columbia County's drinking water come from?

By primary water source, Columbia County's active systems draw on groundwater (13, 100%). Overall, all rely mainly on groundwater (including purchased groundwater) and none on surface water, compared with 94% and 5.7% across Washington. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, Dayton Water Department, draws primarily on groundwater.

What kinds of water systems operate in Columbia County?

Columbia County's active systems break down as 2 community systems (15%), 2 non-transient non-community systems (15%) and 9 transient non-community systems (69%). 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 (62%), local government (15%), state government (15%) and federal government (7.7%).