Public water system · SD4600146
ActiveGrenville
At a glance
Grenville (PWSID SD4600146) is an active community water system in Day County, South Dakota. It reports serving 48 people through 51 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in August 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
48
Service connections
51
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Grenville compare with other water systems in Day County?
By EPA's size categories, Grenville is a very small system (500 people or fewer). Day County has 6 active public water systems, and Grenville is the 6th-largest of them by population served. Its population served is well below the county average of 475 people per system, and accounts for 1.7% 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 Grenville 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 142 South Dakota systems (20%) list purchased surface water as their primary source.
Who owns and regulates Grenville?
EPA lists Grenville 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 Grenville have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in August 2025. The violations listed here began between June 2003 and August 2025. By type: 9 monitoring and reporting, 2 public notice, recordkeeping or other and 1 monitoring. The contaminant or rule involved most often is Lead and Copper Rule (3 of them). 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 |
|---|---|---|---|---|
| 2025-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2017-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2015-08-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2015-08-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2014-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2014-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2003-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2003-06-15 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2003-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | 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.
Grenville: frequently asked questions
Who runs Grenville?
Grenville (PWSID SD4600146) is a community water system owned by a local government. It is regulated by the SD state drinking water program.
How many people does Grenville serve?
Grenville reports serving 48 people through 51 service connections in Day County, South Dakota.
Where does Grenville get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Grenville have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in August 2025. 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 Grenville'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, none is health-based, and the most recent began in August 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the SD state drinking water program.
Where can I find Grenville's water quality report?
As a community water system, Grenville 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
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, “Grenville, PWSID SD4600146, South Dakota”, https://aquacensus.com/water-systems/south-dakota/grenville-sd4600146 (data as of October 1, 2026).