Public water system · CA4810003
ActiveCity of Fairfield
At a glance
City of Fairfield (PWSID CA4810003) is an active community water system in Solano County, California. It reports serving 120,377 people through 32,910 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
120,377
Service connections
32,910
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does City of Fairfield compare with other water systems in Solano County?
By EPA's size categories, City of Fairfield is a very large system (more than 100,000 people). Solano County has 63 active public water systems, and City of Fairfield is the 2nd-largest of them by population served. Its population served is about 16 times the county average of 7,509 people per system, and accounts for 25% of the 473,083 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 Fairfield is about 18 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 609 California systems (8.1%) list surface water as their primary source.
Who owns and regulates City of Fairfield?
EPA lists City of Fairfield 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. 19 of the 63 active systems in Solano County (30%) are also owned by a local government.
Does City of Fairfield have drinking water violations?
EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in October 2024. The violations listed here began between May 1999 and October 2024. By type: 1 reporting, 1 required treatment not met, 1 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Lead and Copper Rule Revisions (2 of them). EPA lists 2 as unaddressed and 2 as resolved. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. 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 |
|---|---|---|---|---|
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2007-12-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 1999-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 4 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 Fairfield: frequently asked questions
Who runs City of Fairfield?
City of Fairfield (PWSID CA4810003) 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 Fairfield serve?
City of Fairfield reports serving 120,377 people through 32,910 service connections in Solano County, California.
Where does City of Fairfield get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does City of Fairfield have any drinking water violations?
EPA's records list 4 violations for this system; 2 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 Fairfield'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 4 violations for this system; 2 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 Fairfield's water quality report?
As a community water system, City of Fairfield 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 Solano County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Vallejo | Solano | 121,420 | Community | Surface water |
| City of Vacaville | Solano | 99,650 | Community | Surface water |
| Suisun-Solano Water Authority | Solano | 29,105 | Community | Surface water |
| City of Benicia | Solano | 27,131 | Community | Surface water |
| California Water Service Co.-Travis Afb | Solano | 18,111 | Community | Purchased surface water |
| City of Dixon | Solano | 12,540 | 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, “City of Fairfield, PWSID CA4810003, California”, https://aquacensus.com/water-systems/california/city-of-fairfield-ca4810003 (data as of October 1, 2026).