Public water system · SD4600287
ActiveSaint Onge Sewer & Water Co
At a glance
Saint Onge Sewer & Water Co (PWSID SD4600287) is an active community water system in Lawrence County, South Dakota. It reports serving 255 people through 78 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, 8 are health-based, and the most recent began in July 2006.
This page covers its drinking water system only; sewer and wastewater service are not part of EPA's drinking water records.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
255
Service connections
78
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Saint Onge Sewer & Water Co compare with other water systems in Lawrence County?
By EPA's size categories, Saint Onge Sewer & Water Co is a very small system (500 people or fewer). Lawrence County has 73 active public water systems. Its population served is about 32% below the county average of 373 people per system, and accounts for 0.9% of the 27,194 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 Saint Onge Sewer & Water Co 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 Saint Onge Sewer & Water Co?
EPA lists Saint Onge Sewer & Water Co 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. 10 of the 73 active systems in Lawrence County (14%) are also owned by a local government.
Does Saint Onge Sewer & Water Co have drinking water violations?
Of the 12 most recent violations in EPA's records, 8 are health-based, and the most recent began in July 2006. The violations listed here began between April 1996 and July 2006. By type: 8 contaminant level above the legal limit, 2 public notice, recordkeeping or other and 2 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (11 of them). EPA lists 9 as resolved and 3 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2006-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2006-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2004-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2004-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2001-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2001-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2000-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1999-10-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1997-10-13 | Public notice, recordkeeping or otherNotification, Public · code 06 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1997-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1997-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1996-04-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Archived |
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.
Saint Onge Sewer & Water Co: frequently asked questions
Who runs Saint Onge Sewer & Water Co?
Saint Onge Sewer & Water Co (PWSID SD4600287) is a community water system owned by a local government. It is regulated by the SD state drinking water program.
How many people does Saint Onge Sewer & Water Co serve?
Saint Onge Sewer & Water Co reports serving 255 people through 78 service connections in Lawrence County, South Dakota.
Where does Saint Onge Sewer & Water Co 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 Saint Onge Sewer & Water Co have any drinking water violations?
Of the 12 most recent violations in EPA's records, 8 are health-based, and the most recent began in July 2006. 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 Saint Onge Sewer & Water Co'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, 8 are health-based, and the most recent began in July 2006. For current results, consult the system's annual water quality report, EPA ECHO, or the SD state drinking water program.
Where can I find Saint Onge Sewer & Water Co's water quality report?
As a community water system, Saint Onge Sewer & Water Co 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 Lawrence County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Spearfish | Lawrence | 13,803 | Community | Groundwater |
| Lead | Lawrence | 2,982 | Community | Purchased surface water |
| Deadwood | Lawrence | 1,156 | Community | Purchased surface water |
| Whitewood | Lawrence | 879 | Community | Groundwater |
| Guadalajara Mexican Restaurant | Lawrence | 630 | Transient non-community | Groundwater |
| Spearfish Canyon Resort LLC | Lawrence | 492 | Transient non-community | Groundwater |
Related pages
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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, “Saint Onge Sewer & Water Co, PWSID SD4600287, South Dakota”, https://aquacensus.com/water-systems/south-dakota/saint-onge-sewer-water-co-sd4600287 (data as of October 1, 2026).