Public water system · IA4843033
ActiveMarengo Water Supply
At a glance
Marengo Water Supply (PWSID IA4843033) is an active community water system in Iowa County, Iowa. It reports serving 2,435 people through 1,020 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, 2 are health-based, and the most recent began in August 2019.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,435
Service connections
1,020
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Marengo Water Supply compare with other water systems in Iowa County?
By EPA's size categories, Marengo Water Supply is a small system (501 to 3,300 people). Iowa County has 15 active public water systems, and Marengo Water Supply is the 3rd-largest of them by population served. Its population served is about 175% above the county average of 884 people per system, and accounts for 18% of the 13,265 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 Marengo Water Supply is about 64% 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. 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 Marengo Water Supply?
EPA lists Marengo 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. 7 of the 15 active systems in Iowa County (47%) are also owned by a local government.
Does Marengo Water Supply have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in August 2019. The violations listed here began between April 1990 and August 2019. By type: 9 monitoring and reporting, 2 contaminant level above the legal limit and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 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 |
|---|---|---|---|---|
| 2019-08-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2019-08-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2016-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2006-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2001-05-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2000-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 1997-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1995-12-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1992-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1991-04-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1991-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1990-04-01 | 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.
Marengo Water Supply: frequently asked questions
Who runs Marengo Water Supply?
Marengo Water Supply (PWSID IA4843033) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Marengo Water Supply serve?
Marengo Water Supply reports serving 2,435 people through 1,020 service connections in Iowa County, Iowa.
Where does Marengo 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 Marengo Water Supply have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in August 2019. 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 Marengo 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, 2 are health-based, and the most recent began in August 2019. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Marengo Water Supply's water quality report?
As a community water system, Marengo 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 Iowa County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Williamsburg Public Water Supply | Iowa | 3,345 | Community | Groundwater |
| Poweshiek Water Association (Iac) | Iowa | 2,490 | Community | Groundwater |
| Amana Society Water System North | Iowa | 1,248 | Community | Groundwater |
| North English Water Department | Iowa | 1,065 | Community | Groundwater |
| Victor Municipal Water Dept | Iowa | 875 | Community | Groundwater |
| Kinze Manufacturing Inc. | Iowa | 710 | Non-transient non-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, “Marengo Water Supply, PWSID IA4843033, Iowa”, https://aquacensus.com/water-systems/iowa/marengo-water-supply-ia4843033 (data as of October 1, 2026).