Public water system · OR4100579
ActiveNyssa, City of
At a glance
City of Nyssa (PWSID OR4100579) is an active community water system in Malheur County, Oregon. It reports serving 3,285 people through 1,126 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, 2 are health-based, and the most recent began in June 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
3,285
Service connections
1,126
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of Nyssa compare with other water systems in Malheur County?
By EPA's size categories, City of Nyssa is a small system (501 to 3,300 people). Malheur County has 20 active public water systems, and City of Nyssa is the 2nd-largest of them by population served. Its population served is about 3.1 times the county average of 1,067 people per system, and accounts for 15% of the 21,335 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 Nyssa is about half of 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 means the system draws its water from wells or springs fed by underground aquifers. 2,175 Oregon systems (86%) list groundwater as their primary source.
Who owns and regulates City of Nyssa?
EPA lists City of Nyssa 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 20 active systems in Malheur County (40%) are also owned by a local government.
Does City of Nyssa have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in June 2025. The violations listed here began between April 2018 and June 2025. By type: 4 public notice, recordkeeping or other, 4 monitoring and reporting, 2 monitoring and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Consumer Confidence 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 |
|---|---|---|---|---|
| 2025-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2024-05-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2022-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2022-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2019-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2019-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2018-11-25 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2018-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2018-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | 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 Nyssa: frequently asked questions
Who runs City of Nyssa?
City of Nyssa (PWSID OR4100579) 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 Nyssa serve?
City of Nyssa reports serving 3,285 people through 1,126 service connections in Malheur County, Oregon.
Where does City of Nyssa 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 City of Nyssa have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in June 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 City of Nyssa'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, 2 are health-based, and the most recent began in June 2025. 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 Nyssa's water quality report?
As a community water system, City of Nyssa 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 Malheur County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Ontario, City of | Malheur | 14,465 | Community | Surface water |
| Vale, City of | Malheur | 1,837 | Community | Groundwater |
| Fry Foods | Malheur | 280 | Non-transient non-community | Groundwater |
| Oprd Mccormack Cg | Malheur | 250 | Transient non-community | Groundwater |
| Jordan Valley, City of | Malheur | 175 | Community | Groundwater |
| Harper High/Elementary Sd 66 | Malheur | 170 | Non-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, “Nyssa, City of, PWSID OR4100579, Oregon”, https://aquacensus.com/water-systems/oregon/nyssa-city-of-or4100579 (data as of October 1, 2026).