Public water system · CA4710002

Active

Dunsmuir, City of

At a glance

City of Dunsmuir (PWSID CA4710002) is an active community water system in Siskiyou County, California. It reports serving 1,707 people through 1,187 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 10 violations for this system; 6 are health-based, and the most recent began in October 2024.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

1,707

Service connections

1,187

Primary source

Groundwater

System type

CWS

Community water system

System record

PWSIDCA4710002

System typeCommunity water system

Activity statusActive

Population served1,707

Service connections1,187

Primary water sourceGroundwater

Owner typeLocal government

Primacy agencyCA state drinking water program

City servedDunsmuir

StateCalifornia

ZIP—

CountySiskiyou County

How does City of Dunsmuir compare with other water systems in Siskiyou County?

By EPA's size categories, City of Dunsmuir is a small system (501 to 3,300 people). Siskiyou County has 69 active public water systems. Its population served is about 188% above the county average of 593 people per system, and accounts for 4.2% of the 40,908 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 Dunsmuir 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. 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 City of Dunsmuir?

EPA lists City of Dunsmuir 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. 21 of the 69 active systems in Siskiyou County (30%) are also owned by a local government.

Does City of Dunsmuir have drinking water violations?

EPA's records list 10 violations for this system; 6 are health-based, and the most recent began in October 2024. The violations listed here began between August 1992 and October 2024. By type: 4 required treatment not met, 2 contaminant level above the legal limit, 2 monitoring and reporting, 1 reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 8 as resolved and 2 as addressed. 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. Addressed means the violation is not resolved or archived and is covered by formal enforcement.

Began	Violation	Contaminant or rule	Health-based	Status
2024-10-17	ReportingLSL Reporting · code 4G	Lead and Copper Rule Revisionscode 5200	No	Addressed
2024-10-17	Required treatment not metLSL Inventory · code 2E	Lead and Copper Rule Revisionscode 5200	Yes	Addressed
2019-04-01	Required treatment not metTreatment Technique, Level 1 Assessment (RTCR) · code 2A	Revised Total Coliform Rulecode 8000	Yes	Resolved
2019-03-01	Required treatment not metTreatment Technique, Level 1 Assessment (RTCR) · code 2A	Revised Total Coliform Rulecode 8000	Yes	Resolved
2016-01-10	Required treatment not metTreatment Technique No Certif. Operator · code 12	Stage 1 Disinfectants and Disinfection Byproducts Rulecode 0400	Yes	Resolved
2015-10-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
2012-02-01	Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31	Groundwater Rulecode 0700	No	Resolved
2012-02-01	Public notice, recordkeeping or otherNotification, Public · code 06	Not reported	No	Resolved
2012-02-01	Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25	Total coliform bacteria (TCR)code 3100	No	Resolved
1992-08-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved

All 10 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 Dunsmuir: frequently asked questions

Who runs City of Dunsmuir?

City of Dunsmuir (PWSID CA4710002) 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 Dunsmuir serve?

City of Dunsmuir reports serving 1,707 people through 1,187 service connections in Siskiyou County, California.

Where does City of Dunsmuir 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 Dunsmuir have any drinking water violations?

EPA's records list 10 violations for this system; 6 are health-based, and the most recent began in October 2024. 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 Dunsmuir'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 10 violations for this system; 6 are health-based, and the most recent began in October 2024. 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 Dunsmuir's water quality report?

As a community water system, City of Dunsmuir 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 Siskiyou County

Water system	County	Population served	Type	Source
Yreka, City of	Siskiyou	7,825	Community	Surface water
Mt. Shasta, City of	Siskiyou	3,642	Community	Groundwater
Mt. Shasta Ski Park	Siskiyou	3,500	Transient non-community	Groundwater
Lake Shastina C.S.D	Siskiyou	2,790	Community	Groundwater
Weed, City of	Siskiyou	2,662	Community	Groundwater
Lake Siskiyou Campground	Siskiyou	1,800	Transient non-community	Surface water

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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, “Dunsmuir, City of, PWSID CA4710002, California”, https://aquacensus.com/water-systems/california/dunsmuir-city-of-ca4710002 (data as of October 1, 2026).