Public water system · CA0310004
ActivePlymouth, City of
At a glance
City of Plymouth (PWSID CA0310004) is an active community water system in Amador County, California. It reports serving 1,060 people through 535 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, 2 are health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,060
Service connections
535
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does City of Plymouth compare with other water systems in Amador County?
By EPA's size categories, City of Plymouth is a small system (501 to 3,300 people). Amador County has 67 active public water systems. Its population served is about 64% above the county average of 645 people per system, and accounts for 2.5% of the 43,217 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active community water system reports serving 6,703 people, so City of Plymouth 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. California has 2,997 active community water systems, 40% of the state's 7,479 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 506 California systems (6.8%) list purchased surface water as their primary source.
Who owns and regulates City of Plymouth?
EPA lists City of Plymouth as owned by a local government. 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. 16 of the 67 active systems in Amador County (24%) are also owned by a local government.
Does City of Plymouth have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2025. The violations listed here began between January 2000 and July 2025. By type: 4 monitoring, 4 monitoring and reporting, 2 contaminant level above the legal limit, 1 reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Revised Total Coliform Rule (4 of them). EPA lists 11 as resolved 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. 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 |
|---|---|---|---|---|
| 2025-07-02 | ReportingNotification, Known or Potential LSL · code 4H | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2021-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2017-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2016-12-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2001-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2000-01-26 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2000-01-25 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | 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 Plymouth: frequently asked questions
Who runs City of Plymouth?
City of Plymouth (PWSID CA0310004) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does City of Plymouth serve?
City of Plymouth reports serving 1,060 people through 535 service connections in Amador County, California.
Where does City of Plymouth 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 City of Plymouth 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 July 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 Plymouth'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 July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find City of Plymouth's water quality report?
As a community water system, City of Plymouth 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 Amador County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Awa Buckhorn Plant | Amador | 8,791 | Community | Surface water |
| Awa, Ione | Amador | 7,227 | Community | Surface water |
| City of Jackson | Amador | 5,019 | Community | Purchased surface water |
| Awa, Tanner | Amador | 4,940 | Community | Surface water |
| Jackson Valley Irrigation District | Amador | 3,553 | Community | Surface water |
| Awa - Camanche Village | Amador | 2,402 | 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, “Plymouth, City of, PWSID CA0310004, California”, https://aquacensus.com/water-systems/california/plymouth-city-of-ca0310004 (data as of October 1, 2026).