Walworth County, South Dakota — public water systems
At a glance
4 active public water systems are filed under Walworth County, South Dakota in EPA's SDWIS records, together reporting 24,777 people served. The largest is Web Water Development Association, which reports serving 20,750 people. All 4 are community water systems serving people where they live.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
4
Population served
24.8K
Community systems
4
Groundwater share
0%
How does Walworth County compare with other South Dakota counties?
Walworth County has the 40th-most active public water systems among the 73 counties listed for active South Dakota systems in EPA records; among the 48 with 3 or more systems, the median has 6. Its systems report 24,777 people served in total, the 8th-largest county figure in the state and 2.6% of the statewide total. The average system here reports serving 6,194 people, about 4.5 times the South Dakota average of 1,387. 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 Walworth County's drinking water come from?
By primary water source, Walworth County's active systems draw on purchased surface water (2, 50%) and surface water (2, 50%). Overall, none rely mainly on groundwater (including purchased groundwater) and all on surface water, compared with 76% and 24% across South Dakota. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. The county's largest system, Web Water Development Association, draws primarily on surface water.
What kinds of water systems operate in Walworth County?
Walworth County's active systems break down as 4 community systems (100%). 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. EPA lists their owner types as local government (75%) and private (25%).
Water systems in Walworth County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Web Water Development Association | Walworth + 9 more | 20,750 | Community | Surface water |
| 2 | Mobridge | Walworth | 3,261 | Community | Surface water |
| 3 | Selby | Walworth | 645 | Community | Purchased surface water |
| 4 | Java | Walworth | 121 | Community | Purchased surface water |
Walworth County water systems: frequently asked questions
How many public water systems are in Walworth County, South Dakota?
EPA's SDWIS records file 4 active public water systems under Walworth County, South Dakota: 4 community systems (100%).
Who supplies drinking water in Walworth County, SD?
The largest community water systems filed under Walworth County are Web Water Development Association (20,750 people served), Mobridge (3,261 people served) and Selby (645 people served). Which system serves a particular address depends on its service area, which EPA's SDWIS records do not include; a water bill or the local utility can confirm it.
Does Walworth County's drinking water come from groundwater or surface water?
Of the 4 active public water systems in Walworth County, none draw mainly on groundwater and all on surface water, counting purchased supplies. The largest system, Web Water Development Association, uses surface water.
Where can I find a water quality report for Walworth County?
Each community water system must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1, covering the previous calendar year. 4 community systems are filed under Walworth County, so the report to look for is the one from the system that supplies your address.
How can I check violations for a water system in Walworth County?
Open the system's profile from the list on this page. Each profile shows the most recent Safe Drinking Water Act violations in EPA's records, with plain-English labels and whether each one is resolved. For current compliance status, EPA ECHO is the primary source.
More South Dakota water systems
About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Public water systems in Walworth County, South Dakota”, https://aquacensus.com/water-systems/south-dakota/walworth (data as of October 1, 2026).