Public water system · IA5131033
ActiveFairfield Water Supply
At a glance
Fairfield Water Supply (PWSID IA5131033) is an active community water system in Jefferson County, Iowa. It reports serving 9,821 people through 5,250 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in January 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
9,821
Service connections
5,250
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Fairfield Water Supply compare with other water systems in Jefferson County?
By EPA's size categories, Fairfield Water Supply is a medium system (3,301 to 10,000 people). Jefferson County has 8 active public water systems, and Fairfield Water Supply is the largest of them by population served. Its population served is about 6.8 times the county average of 1,442 people per system, and accounts for 85% of the 11,535 people reported by systems filed under the county. Across Iowa, the 1,828 active systems average 1,718 people each. Nationally, the average active community water system reports serving 6,703 people, so Fairfield Water Supply is about 47% above 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. Iowa has 1,084 active community water systems, 59% of the state's 1,828 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,502 Iowa systems (82%) list groundwater as their primary source.
Who owns and regulates Fairfield Water Supply?
EPA lists Fairfield Water Supply as owned by a local government. The IA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 5 of the 8 active systems in Jefferson County (63%) are also owned by a local government.
Does Fairfield Water Supply have drinking water violations?
Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in January 2023. The violations listed here began between October 1994 and January 2023. By type: 6 required treatment not met, 5 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Surface Water Treatment Rule (6 of them). EPA lists 7 as archived and 5 as resolved. 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. 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 |
|---|---|---|---|---|
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Archived |
| 2013-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2013-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2004-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1998-07-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 1998-05-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 1997-08-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 1997-07-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 1997-06-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 1996-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Atrazinecode 2050 | No | Resolved |
| 1995-01-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1994-10-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
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.
Fairfield Water Supply: frequently asked questions
Who runs Fairfield Water Supply?
Fairfield Water Supply (PWSID IA5131033) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Fairfield Water Supply serve?
Fairfield Water Supply reports serving 9,821 people through 5,250 service connections in Jefferson County, Iowa.
Where does Fairfield Water Supply 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 Fairfield Water Supply have any drinking water violations?
Of the 12 most recent violations in EPA's records, 7 are health-based, and the most recent began in January 2023. 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 Fairfield Water Supply'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, 7 are health-based, and the most recent began in January 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Fairfield Water Supply's water quality report?
As a community water system, Fairfield Water Supply 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 Jefferson County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Jefferson County Rural Water District | Jefferson | 468 | Community | Purchased surface water |
| Batavia Water Works | Jefferson | 430 | Community | Purchased surface water |
| Libertyville Water Works | Jefferson | 304 | Community | Purchased groundwater |
| Lockridge Muni Water Supply | Jefferson | 244 | Community | Purchased groundwater |
| Fairfield Estates Mobile Home Park | Jefferson | 140 | Community | Purchased groundwater |
| Ila Campus LLC | Jefferson | 68 | Community | Purchased 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, “Fairfield Water Supply, PWSID IA5131033, Iowa”, https://aquacensus.com/water-systems/iowa/fairfield-water-supply-ia5131033 (data as of October 1, 2026).