Public water system · IA2742076
ActiveLeon Water Supply
At a glance
Leon Water Supply (PWSID IA2742076) is an active community water system in Decatur County, Iowa. It reports serving 1,830 people through 825 service connections. Its primary water source is surface water, 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 July 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,830
Service connections
825
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Leon Water Supply compare with other water systems in Decatur County?
By EPA's size categories, Leon Water Supply is a small system (501 to 3,300 people). Decatur County has 5 active public water systems, and Leon Water Supply is the 3rd-largest of them by population served. Its population served is well below the county average of 7,682 people per system, and accounts for 4.8% of the 38,411 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 Leon Water Supply 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. Iowa has 1,084 active community water systems, 59% of the state's 1,828 active systems. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 24 Iowa systems (1.3%) list surface water as their primary source.
Who owns and regulates Leon Water Supply?
EPA lists Leon 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. 3 of the 5 active systems in Decatur County (60%) are also owned by a local government.
Does Leon 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 July 2023. The violations listed here began between July 1989 and July 2023. By type: 5 monitoring and reporting, 4 contaminant level above the legal limit and 3 required treatment not met. The contaminant or rule involved most often is Surface Water Treatment Rule (3 of them). EPA lists 12 as resolved. 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 |
|---|---|---|---|---|
| 2023-07-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2022-09-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2022-08-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2022-02-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2022-02-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2018-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Resolved |
| 2016-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2016-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2016-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2016-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 1995-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Atrazinecode 2050 | No | Resolved |
| 1989-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | 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.
Leon Water Supply: frequently asked questions
Who runs Leon Water Supply?
Leon Water Supply (PWSID IA2742076) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Leon Water Supply serve?
Leon Water Supply reports serving 1,830 people through 825 service connections in Decatur County, Iowa.
Where does Leon Water Supply 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 Leon 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 July 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 Leon 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 July 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 Leon Water Supply's water quality report?
As a community water system, Leon 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 Decatur County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Rathbun Regional Water Assn (Rathbun) | Decatur + 7 more | 33,000 | Community | Surface water |
| Lamoni Municipal Utilities | Decatur | 2,029 | Community | Surface water |
| Sirwa #3 (Leon) | Decatur | 1,373 | Community | Purchased surface water |
| Garden Grove Water Supply | Decatur | 179 | Community | Purchased 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, “Leon Water Supply, PWSID IA2742076, Iowa”, https://aquacensus.com/water-systems/iowa/leon-water-supply-ia2742076 (data as of October 1, 2026).