Public water system · IA1535078
ActiveLewis Water Supply
At a glance
Lewis Water Supply (PWSID IA1535078) is an active community water system in Cass County, Iowa. It reports serving 357 people through 200 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 9 violations for this system; 7 are health-based, and the most recent began in October 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
357
Service connections
200
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Lewis Water Supply compare with other water systems in Cass County?
By EPA's size categories, Lewis Water Supply is a very small system (500 people or fewer). Cass County has 15 active public water systems, and Lewis Water Supply is the 5th-largest of them by population served. Its population served is about half of the county average of 732 people per system, and accounts for 3.3% of the 10,975 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 Lewis 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 Lewis Water Supply?
EPA lists Lewis 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 15 active systems in Cass County (53%) are also owned by a local government.
Does Lewis Water Supply have drinking water violations?
EPA's records list 9 violations for this system; 7 are health-based, and the most recent began in October 2025. The violations listed here began between December 1978 and October 2025. By type: 7 contaminant level above the legal limit and 2 monitoring and reporting. The contaminant or rule involved most often is Nitrate (6 of them). EPA lists 7 as resolved and 2 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 |
|---|---|---|---|---|
| 2025-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2025-03-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Resolved |
| 2003-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Resolved |
| 1998-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Resolved |
| 1993-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1993-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1992-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Resolved |
| 1981-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Archived |
| 1978-12-20 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Archived |
All 9 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.
Lewis Water Supply: frequently asked questions
Who runs Lewis Water Supply?
Lewis Water Supply (PWSID IA1535078) is a community water system owned by a local government. It is regulated by the IA state drinking water program.
How many people does Lewis Water Supply serve?
Lewis Water Supply reports serving 357 people through 200 service connections in Cass County, Iowa.
Where does Lewis 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 Lewis Water Supply have any drinking water violations?
EPA's records list 9 violations for this system; 7 are health-based, and the most recent began in October 2025. 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 Lewis 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 9 violations for this system; 7 are health-based, and the most recent began in October 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Lewis Water Supply's water quality report?
As a community water system, Lewis 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 Cass County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Atlantic Municipal Utilities | Cass | 7,252 | Community | Groundwater |
| Griswold Water Supply | Cass | 1,008 | Community | Groundwater |
| Anita Municipal Utilities | Cass | 972 | Community | Groundwater |
| Massena Water Supply | Cass | 364 | Community | Groundwater |
| Cumberland Water Supply | Cass | 266 | Community | Groundwater |
| Hitchcock House | Cass | 216 | 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, “Lewis Water Supply, PWSID IA1535078, Iowa”, https://aquacensus.com/water-systems/iowa/lewis-water-supply-ia1535078 (data as of October 1, 2026).