Public water system · CA5000483
ActiveRiver Oak Grace-Water System
At a glance
River Oak Grace-Water System (PWSID CA5000483) is an active transient non-community water system in Stanislaus County, California. It reports serving 500 people through 3 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 7 violations for this system; 6 are health-based, and the most recent began in January 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
500
Service connections
3
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does River Oak Grace-Water System compare with other water systems in Stanislaus County?
By EPA's size categories, River Oak Grace-Water System is a very small system (500 people or fewer). Stanislaus County has 191 active public water systems. Its population served is well below the county average of 2,684 people per system, and accounts for less than 0.1% of the 512,656 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active transient non-community water system reports serving 144 people, so River Oak Grace-Water System is about 3.5 times that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. California has 3,016 active transient non-community water systems, 40% of the state's 7,479 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,179 California systems (83%) list groundwater as their primary source.
Who owns and regulates River Oak Grace-Water System?
EPA lists River Oak Grace-Water System as privately owned. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 130 of the 191 active systems in Stanislaus County (68%) are also privately owned.
Does River Oak Grace-Water System have drinking water violations?
EPA's records list 7 violations for this system; 6 are health-based, and the most recent began in January 2025. The violations listed here began between October 2021 and January 2025. By type: 6 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Nitrate (7 of them). EPA lists 7 as archived. 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 |
|---|---|---|---|---|
| 2025-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2024-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2023-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2023-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2023-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Archived |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 2021-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Archived |
All 7 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.
River Oak Grace-Water System: frequently asked questions
Who runs River Oak Grace-Water System?
River Oak Grace-Water System (PWSID CA5000483) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does River Oak Grace-Water System serve?
River Oak Grace-Water System reports serving 500 people through 3 service connections in Stanislaus County, California.
Where does River Oak Grace-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 River Oak Grace-Water System have any drinking water violations?
EPA's records list 7 violations for this system; 6 are health-based, and the most recent began in January 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 River Oak Grace-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. EPA's records list 7 violations for this system; 6 are health-based, and the most recent began in January 2025. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find River Oak Grace-Water System's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. River Oak Grace-Water System is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Stanislaus County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Modesto, City of | Stanislaus | 218,771 | Community | Purchased surface water |
| Turlock, City of | Stanislaus | 72,682 | Community | Purchased surface water |
| Ceres, City of | Stanislaus | 54,513 | Community | Purchased surface water |
| Patterson, City of | Stanislaus | 24,977 | Community | Groundwater |
| Riverbank, City of | Stanislaus | 24,834 | Community | Groundwater |
| Oakdale, City of | Stanislaus | 23,235 | 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, “River Oak Grace-Water System, PWSID CA5000483, California”, https://aquacensus.com/water-systems/california/river-oak-grace-water-system-ca5000483 (data as of October 1, 2026).