Public water system · NM3527231
ActiveGrenville Water System
At a glance
Grenville Water System (PWSID NM3527231) is an active community water system in Union County, New Mexico. It reports serving 45 people through 18 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 October 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
45
Service connections
18
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Grenville Water System compare with other water systems in Union County?
By EPA's size categories, Grenville Water System is a very small system (500 people or fewer). Union County has 8 active public water systems. Its population served is well below the county average of 587 people per system, and accounts for 1% of the 4,699 people reported by systems filed under the county. Across New Mexico, the 1,165 active systems average 1,885 people each. Nationally, the average active community water system reports serving 6,703 people, so Grenville Water System 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. New Mexico has 645 active community water systems, 55% of the state's 1,165 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,009 New Mexico systems (87%) list groundwater as their primary source.
Who owns and regulates Grenville Water System?
EPA lists Grenville Water System as owned by a local government. The NM state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 4 of the 8 active systems in Union County (50%) are also owned by a local government.
Does Grenville Water System have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2025. The violations listed here began between June 2021 and October 2025. By type: 7 public notice, recordkeeping or other, 2 monitoring and reporting, 2 monitoring and 1 required treatment not met. The contaminant or rule involved most often is Public Notice (4 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 |
|---|---|---|---|---|
| 2025-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2022-11-06 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2022-07-28 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2022-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2022-05-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-12-19 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2021-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2021-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2021-09-15 | Required treatment not metTreatment Technique, Level 1 Assessment (RTCR) · code 2A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2021-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2021-06-26 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | 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 Water System: frequently asked questions
Who runs Grenville Water System?
Grenville Water System (PWSID NM3527231) is a community water system owned by a local government. It is regulated by the NM state drinking water program.
How many people does Grenville Water System serve?
Grenville Water System reports serving 45 people through 18 service connections in Union County, New Mexico.
Where does Grenville Water System 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 Grenville Water System 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 October 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 Water System'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 October 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the NM state drinking water program.
Where can I find Grenville Water System's water quality report?
As a community water system, Grenville Water System 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 Union County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Clayton Municipal Supply | Union | 3,250 | Community | Groundwater |
| Northeast Nm Detention Facility | Union | 703 | Non-transient non-community | Groundwater |
| Des Moines Water System | Union | 218 | Community | Groundwater |
| Clayton Lake State Park | Union | 178 | Transient non-community | Groundwater |
| Capulin Volcano National Monument | Union | 175 | Transient non-community | Groundwater |
| Sierra Grande Highway Rest Area | Union | 75 | Transient non-community | Groundwater |
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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 Water System, PWSID NM3527231, New Mexico”, https://aquacensus.com/water-systems/new-mexico/grenville-water-system-nm3527231 (data as of October 1, 2026).