Public water system · IA4652011
ActiveOttosen Water Supply
At a glance
Ottosen Water Supply (PWSID IA4652011) is an active community water system in Humboldt County, Iowa. It reports serving 41 people through 31 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 7 violations for this system; 1 is health-based, and the most recent began in November 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
41
Service connections
31
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Ottosen Water Supply compare with other water systems in Humboldt County?
By EPA's size categories, Ottosen Water Supply is a very small system (500 people or fewer). Humboldt County has 13 active public water systems. Its population served is well below the county average of 550 people per system, and accounts for 0.6% of the 7,145 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 Ottosen 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. 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 Ottosen Water Supply?
EPA lists Ottosen 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. 11 of the 13 active systems in Humboldt County (85%) are also owned by a local government.
Does Ottosen Water Supply have drinking water violations?
EPA's records list 7 violations for this system; 1 is health-based, and the most recent began in November 2020. The violations listed here began between October 1984 and November 2020. By type: 5 monitoring and reporting, 1 monitoring and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 7 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 |
|---|---|---|---|---|
| 2020-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2014-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Diquatcode 2032 | No | Resolved |
| 1998-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1992-12-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1989-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 1984-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
All 7 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.
Ottosen Water Supply: frequently asked questions
Who runs Ottosen Water Supply?
Ottosen Water Supply (PWSID IA4652011) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Ottosen Water Supply serve?
Ottosen Water Supply reports serving 41 people through 31 service connections in Humboldt County, Iowa.
Where does Ottosen 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 Ottosen Water Supply have any drinking water violations?
EPA's records list 7 violations for this system; 1 is health-based, and the most recent began in November 2020. 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 Ottosen 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 7 violations for this system; 1 is health-based, and the most recent began in November 2020. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Ottosen Water Supply's water quality report?
As a community water system, Ottosen 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 Humboldt County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Humboldt Municipal Water Dept | Humboldt | 4,792 | Community | Groundwater under influence of surface water |
| Dakota City Water Supply | Humboldt | 769 | Community | Groundwater |
| Livermore Water Supply | Humboldt | 383 | Community | Groundwater |
| Bode Municipal Water Supply | Humboldt | 304 | Community | Groundwater |
| Renwick Munic Water Supply | Humboldt | 234 | Community | Groundwater |
| Thor Water Works | Humboldt | 181 | 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, “Ottosen Water Supply, PWSID IA4652011, Iowa”, https://aquacensus.com/water-systems/iowa/ottosen-water-supply-ia4652011 (data as of October 1, 2026).