Public water system · OR4100541
ActiveMonument, City of
At a glance
City of Monument (PWSID OR4100541) is an active community water system in Grant County, Oregon. It reports serving 115 people through 91 service connections. Its primary water source is groundwater under influence of surface water, 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 January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
115
Service connections
91
Primary source
GU
Groundwater under influence of surface water
System type
CWS
Community water system
System record
How does City of Monument compare with other water systems in Grant County?
By EPA's size categories, City of Monument is a very small system (500 people or fewer). Grant County has 15 active public water systems. Its population served is about 66% below the county average of 339 people per system, and accounts for 2.3% of the 5,090 people reported by systems filed under the county. Across Oregon, the 2,536 active systems average 1,587 people each. Nationally, the average active community water system reports serving 6,703 people, so City of Monument 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. Oregon has 940 active community water systems, 37% of the state's 2,536 active systems. Groundwater under the influence of surface water is well or spring water that the regulator has found to be affected by nearby surface water, so it is regulated under the surface-water treatment rules. 21 Oregon systems (0.8%) list groundwater under influence of surface water as their primary source.
Who owns and regulates City of Monument?
EPA lists City of Monument as owned by a local government. The OR state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 8 of the 15 active systems in Grant County (53%) are also owned by a local government.
Does City of Monument have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2026. The violations listed here began between July 2025 and January 2026. By type: 10 monitoring and reporting, 1 required treatment not met and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Surface Water Treatment Rule (9 of them). EPA lists 10 as resolved, 1 as archived and 1 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2026-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Xylenes, Totalcode 2955 | No | Archived |
| 2025-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2025-09-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-09-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-09-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-08-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-08-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2025-08-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-08-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | 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.
City of Monument: frequently asked questions
Who runs City of Monument?
City of Monument (PWSID OR4100541) is a community water system owned by a local government. It is regulated by the OR state drinking water program.
How many people does City of Monument serve?
City of Monument reports serving 115 people through 91 service connections in Grant County, Oregon.
Where does City of Monument get its water?
EPA SDWIS lists this system's primary water source as groundwater under influence of surface water. Groundwater under the influence of surface water is well or spring water that the regulator has found to be affected by nearby surface water, so it is regulated under the surface-water treatment rules.
Does City of Monument 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 January 2026. 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 City of Monument'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 January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the OR state drinking water program.
Where can I find City of Monument's water quality report?
As a community water system, City of Monument 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 Grant County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| John Day, City of | Grant | 1,617 | Community | Groundwater |
| Prairie City | Grant | 841 | Community | Groundwater under influence of surface water |
| Canyon City Water Department | Grant | 666 | Community | Groundwater under influence of surface water |
| Mount Vernon, City of | Grant | 510 | Community | Groundwater |
| Oprd Clyde Holliday Wayside | Grant | 450 | Transient non-community | Groundwater |
| Seneca, City of | Grant | 200 | 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, “Monument, City of, PWSID OR4100541, Oregon”, https://aquacensus.com/water-systems/oregon/monument-city-of-or4100541 (data as of October 1, 2026).