Public water system · IA6436087
ActiveGilman Water Supply
At a glance
Gilman Water Supply (PWSID IA6436087) is an active community water system in Marshall County, Iowa. It reports serving 582 people through 249 service connections. Its primary water source is purchased groundwater, and EPA lists it as owned by a local government. EPA's records list 8 violations for this system; 7 are health-based, and the most recent began in May 1999.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
582
Service connections
249
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Gilman Water Supply compare with other water systems in Marshall County?
By EPA's size categories, Gilman Water Supply is a small system (501 to 3,300 people). Marshall County has 12 active public water systems, and Gilman Water Supply is the 5th-largest of them by population served. Its population served is well below the county average of 2,802 people per system, and accounts for 1.7% of the 33,628 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 Gilman 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. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own. 156 Iowa systems (8.5%) list purchased groundwater as their primary source.
Who owns and regulates Gilman Water Supply?
EPA lists Gilman 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. 10 of the 12 active systems in Marshall County (83%) are also owned by a local government.
Does Gilman Water Supply have drinking water violations?
EPA's records list 8 violations for this system; 7 are health-based, and the most recent began in May 1999. The violations listed here began between January 1983 and May 1999. By type: 7 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Nitrate (6 of them). EPA lists 5 as archived and 3 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 |
|---|---|---|---|---|
| 1999-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1991-05-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1985-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Archived |
| 1985-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Archived |
| 1984-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 1984-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Resolved |
| 1983-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 1983-01-11 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
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.
Gilman Water Supply: frequently asked questions
Who runs Gilman Water Supply?
Gilman Water Supply (PWSID IA6436087) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Gilman Water Supply serve?
Gilman Water Supply reports serving 582 people through 249 service connections in Marshall County, Iowa.
Where does Gilman Water Supply get its water?
EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.
Does Gilman Water Supply have any drinking water violations?
EPA's records list 8 violations for this system; 7 are health-based, and the most recent began in May 1999. 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 Gilman 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; 7 are health-based, and the most recent began in May 1999. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Gilman Water Supply's water quality report?
As a community water system, Gilman 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 Marshall County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Marshalltown Water Works | Marshall | 27,680 | Community | Groundwater |
| State Center Muni Water Dept | Marshall | 1,411 | Community | Groundwater |
| Le Grand Water Works | Marshall | 910 | Community | Purchased groundwater |
| Melbourne Water Supply | Marshall | 765 | Community | Purchased groundwater |
| Sunset Village | Marshall | 528 | Community | Purchased groundwater |
| Albion Water Department | Marshall | 448 | 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, “Gilman Water Supply, PWSID IA6436087, Iowa”, https://aquacensus.com/water-systems/iowa/gilman-water-supply-ia6436087 (data as of October 1, 2026).