Hamlin County, South Dakota — public water systems
At a glance
6 active public water systems are filed under Hamlin County, South Dakota in EPA's SDWIS records, together reporting 7,145 people served. The largest is Sioux Rural Water System, which reports serving 4,280 people. All 6 are community water systems serving people where they live.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
6
Population served
7.1K
Community systems
6
Groundwater share
100%
How does Hamlin County compare with other South Dakota counties?
Hamlin County has the 21st-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 7,145 people served in total, the 26th-largest county figure in the state and 0.7% of the statewide total. The average system here reports serving 1,191 people, about 14% below 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 Hamlin County's drinking water come from?
By primary water source, Hamlin County's active systems draw on purchased groundwater (4, 67%) and groundwater (2, 33%). Overall, all rely mainly on groundwater (including purchased groundwater) and none on surface water, compared with 76% and 24% across South Dakota. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own. The county's largest system, Sioux Rural Water System, draws primarily on groundwater.
What kinds of water systems operate in Hamlin County?
Hamlin County's active systems break down as 6 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 (83%) and private (17%).
Water systems in Hamlin County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Sioux Rural Water System | Hamlin + 3 more | 4,280 | Community | Groundwater |
| 2 | Estelline | Hamlin | 749 | Community | Purchased groundwater |
| 3 | Castlewood | Hamlin | 698 | Community | Purchased groundwater |
| 4 | Lake Norden | Hamlin | 554 | Community | Groundwater |
| 5 | Bryant | Hamlin | 471 | Community | Purchased groundwater |
| 6 | Hayti | Hamlin | 393 | Community | Purchased groundwater |
Also serving Hamlin County
These systems serve several counties, including Hamlin County. EPA lists another county first for them, so they are not included in the counts above.
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Clark Rural Water System | Clark + 3 more | 2,325 | Community | Groundwater |
Hamlin County water systems: frequently asked questions
How many public water systems are in Hamlin County, South Dakota?
EPA's SDWIS records file 6 active public water systems under Hamlin County, South Dakota: 6 community systems (100%). At least 1 more system is listed under another county but also serve Hamlin County.
Who supplies drinking water in Hamlin County, SD?
The largest community water systems filed under Hamlin County are Sioux Rural Water System (4,280 people served), Estelline (749 people served) and Castlewood (698 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 Hamlin County's drinking water come from groundwater or surface water?
Of the 6 active public water systems in Hamlin County, all draw mainly on groundwater and none on surface water, counting purchased supplies. The largest system, Sioux Rural Water System, uses groundwater.
Where can I find a water quality report for Hamlin 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. 6 community systems are filed under Hamlin 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 Hamlin 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 Hamlin County, South Dakota”, https://aquacensus.com/water-systems/south-dakota/hamlin (data as of October 1, 2026).