Public water system · SD4600357
ActiveWaubay
At a glance
Waubay (PWSID SD4600357) is an active community water system in Day County, South Dakota. It reports serving 473 people through 300 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in May 2009.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
473
Service connections
300
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Waubay compare with other water systems in Day County?
By EPA's size categories, Waubay is a very small system (500 people or fewer). Day County has 6 active public water systems, and Waubay is the 2nd-largest of them by population served. Its population served is roughly in line with the county average of 475 people per system, and accounts for 17% of the 2,847 people reported by systems filed under the county. Across South Dakota, the 699 active systems average 1,387 people each. Nationally, the average active community water system reports serving 6,703 people, so Waubay is well below that figure.
What does “community water system” mean?
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. South Dakota has 510 active community water systems, 73% of the state's 699 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 431 South Dakota systems (62%) list groundwater as their primary source.
Who owns and regulates Waubay?
EPA lists Waubay as owned by a local government. The SD state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 6 of the 6 active systems in Day County (100%) are also owned by a local government.
Does Waubay have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in May 2009. The violations listed here began between January 2009 and May 2009. By type: 11 monitoring and reporting and 1 required treatment not met. The contaminants or rules involved are Stage 1 Disinfectants and Disinfection Byproducts Rule, Lindane (gamma-BHC), Dinoseb and Toxaphene. EPA lists 12 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2009-05-01 | Required treatment not metTreatment Technique No Certif. Operator · code 12 | Stage 1 Disinfectants and Disinfection Byproducts Rulecode 0400 | Yes | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Lindane (gamma-BHC)code 2010 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dinosebcode 2041 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Toxaphenecode 2020 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Simazinecode 2037 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dalaponcode 2031 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlordanecode 2959 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Pentachlorophenolcode 2326 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Methoxychlorcode 2015 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) adipatecode 2035 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Heptachlor epoxidecode 2067 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Hexachlorobenzenecode 2274 | No | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Waubay: frequently asked questions
Who runs Waubay?
Waubay (PWSID SD4600357) is a community water system owned by a local government. It is regulated by the SD state drinking water program.
How many people does Waubay serve?
Waubay reports serving 473 people through 300 service connections in Day County, South Dakota.
Where does Waubay get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Waubay have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in May 2009. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Waubay's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in May 2009. For current results, consult the system's annual water quality report, EPA ECHO, or the SD state drinking water program.
Where can I find Waubay's water quality report?
As a community water system, Waubay must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Day County
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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, “Waubay, PWSID SD4600357, South Dakota”, https://aquacensus.com/water-systems/south-dakota/waubay-sd4600357 (data as of October 1, 2026).