Public water system · IA9164078
ActiveNorwalk Water Supply
At a glance
Norwalk Water Supply (PWSID IA9164078) is an active community water system in Warren County, Iowa. It reports serving 14,334 people through 5,982 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in August 2011.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
14,334
Service connections
5,982
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Norwalk Water Supply compare with other water systems in Warren County?
By EPA's size categories, Norwalk Water Supply is a large system (10,001 to 100,000 people). Warren County has 14 active public water systems, and Norwalk Water Supply is the 3rd-largest of them by population served. Its population served is about 3.5 times the county average of 4,106 people per system, and accounts for 25% of the 57,488 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 Norwalk Water Supply is about twice 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 119 Iowa systems (6.5%) list purchased surface water as their primary source.
Who owns and regulates Norwalk Water Supply?
EPA lists Norwalk 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. 8 of the 14 active systems in Warren County (57%) are also owned by a local government.
Does Norwalk Water Supply have drinking water violations?
EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in August 2011. The violations listed here began between October 1990 and August 2011. By type: 7 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 of them). EPA lists 7 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 |
|---|---|---|---|---|
| 2011-08-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2003-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2003-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2001-08-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1999-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1993-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
| 1992-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1990-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 8 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.
Norwalk Water Supply: frequently asked questions
Who runs Norwalk Water Supply?
Norwalk Water Supply (PWSID IA9164078) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Norwalk Water Supply serve?
Norwalk Water Supply reports serving 14,334 people through 5,982 service connections in Warren County, Iowa.
Where does Norwalk Water Supply get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Norwalk Water Supply have any drinking water violations?
EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in August 2011. 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 Norwalk 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. EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in August 2011. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Norwalk Water Supply's water quality report?
As a community water system, Norwalk 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 Warren County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Warren Water District | Warren + 1 more | 20,095 | Community | Purchased surface water |
| Indianola Water Supply | Warren | 15,833 | Community | Groundwater |
| Carlisle Water Supply | Warren | 4,170 | Community | Groundwater |
| Milo Public Water Supply | Warren | 788 | Community | Purchased surface water |
| New Virginia Water Supply | Warren | 498 | Community | Purchased surface water |
| Martensdale Water Supply | Warren | 421 | 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, “Norwalk Water Supply, PWSID IA9164078, Iowa”, https://aquacensus.com/water-systems/iowa/norwalk-water-supply-ia9164078 (data as of October 1, 2026).