Public water system · CA4910006
ActivePetaluma, City of
At a glance
City of Petaluma (PWSID CA4910006) is an active community water system in Sonoma County, California. It reports serving 60,781 people through 20,511 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 2 violations for this system; none is health-based, and the most recent began in January 2005.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
60,781
Service connections
20,511
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of Petaluma compare with other water systems in Sonoma County?
By EPA's size categories, City of Petaluma is a large system (10,001 to 100,000 people). Sonoma County has 441 active public water systems, and City of Petaluma is the 2nd-largest of them by population served. Its population served is about 56 times the county average of 1,092 people per system, and accounts for 13% of the 481,435 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 Petaluma is about 9.1 times 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 Petaluma?
EPA lists City of Petaluma 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. 58 of the 441 active systems in Sonoma County (13%) are also owned by a local government.
Does City of Petaluma have drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in January 2005. The violations listed here began between April 1989 and January 2005. By type: 1 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved is Haloacetic acids (HAA5). EPA lists 1 as resolved and 1 as archived. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2005-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 1989-04-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
All 2 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 Petaluma: frequently asked questions
Who runs City of Petaluma?
City of Petaluma (PWSID CA4910006) 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 Petaluma serve?
City of Petaluma reports serving 60,781 people through 20,511 service connections in Sonoma County, California.
Where does City of Petaluma 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 Petaluma have any drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in January 2005. 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 Petaluma'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 2 violations for this system; none is health-based, and the most recent began in January 2005. 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 Petaluma's water quality report?
As a community water system, City of Petaluma 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 Sonoma County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Santa Rosa, City of | Sonoma | 175,396 | Community | Groundwater |
| Rohnert Park, City of | Sonoma | 43,821 | Community | Groundwater |
| Windsor, Town of | Sonoma | 25,561 | Community | Groundwater |
| Valley of the Moon Water District | Sonoma | 23,107 | Community | Groundwater |
| Sonoma, City of | Sonoma | 11,725 | Community | Groundwater |
| Sonoma State University | Sonoma | 10,986 | 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, “Petaluma, City of, PWSID CA4910006, California”, https://aquacensus.com/water-systems/california/petaluma-city-of-ca4910006 (data as of October 1, 2026).