Public water system · IA9630012
ActiveDecorah Water Department
At a glance
Decorah Water Department (PWSID IA9630012) is an active community water system in Winneshiek County, Iowa. It reports serving 7,615 people through 2,800 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 5 violations for this system; none is health-based, and the most recent began in January 2010.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
7,615
Service connections
2,800
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Decorah Water Department compare with other water systems in Winneshiek County?
By EPA's size categories, Decorah Water Department is a medium system (3,301 to 10,000 people). Winneshiek County has 43 active public water systems, and Decorah Water Department is the largest of them by population served. Its population served is about 22 times the county average of 343 people per system, and accounts for 52% of the 14,733 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 Decorah Water Department is about 14% 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 Decorah Water Department?
EPA lists Decorah Water Department 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. 13 of the 43 active systems in Winneshiek County (30%) are also owned by a local government.
Does Decorah Water Department have drinking water violations?
EPA's records list 5 violations for this system; none is health-based, and the most recent began in January 2010. The violations listed here began between October 1995 and January 2010. By type: 5 monitoring and reporting. The contaminant or rule involved most often is Vinyl chloride (3 of them). EPA lists 5 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 |
|---|---|---|---|---|
| 2010-01-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2007-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1995-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Resolved |
| 1995-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Resolved |
| 1995-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Resolved |
All 5 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.
Decorah Water Department: frequently asked questions
Who runs Decorah Water Department?
Decorah Water Department (PWSID IA9630012) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Decorah Water Department serve?
Decorah Water Department reports serving 7,615 people through 2,800 service connections in Winneshiek County, Iowa.
Where does Decorah Water Department 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 Decorah Water Department have any drinking water violations?
EPA's records list 5 violations for this system; none is health-based, and the most recent began in January 2010. 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 Decorah Water Department'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 5 violations for this system; none is health-based, and the most recent began in January 2010. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Decorah Water Department's water quality report?
As a community water system, Decorah Water Department 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 Winneshiek County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Calmar Water Supply | Winneshiek | 1,125 | Community | Groundwater |
| Ossian Water Supply | Winneshiek | 802 | Community | Groundwater |
| Freeport Water District | Winneshiek | 775 | Community | Groundwater |
| The Country Express | Winneshiek | 515 | Transient non-community | Groundwater |
| Turkey Valley Community School | Winneshiek | 490 | Non-transient non-community | Groundwater |
| Spillville Water Supply | Winneshiek | 371 | 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, “Decorah Water Department, PWSID IA9630012, Iowa”, https://aquacensus.com/water-systems/iowa/decorah-water-department-ia9630012 (data as of October 1, 2026).