Public water system · ID3140074
ActiveMiddleton City of
At a glance
City of Middleton (PWSID ID3140074) is an active community water system in Canyon County, Idaho. It reports serving 13,190 people through 5,135 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in December 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
13,190
Service connections
5,135
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does City of Middleton compare with other water systems in Canyon County?
By EPA's size categories, City of Middleton is a large system (10,001 to 100,000 people). Canyon County has 140 active public water systems, and City of Middleton is the 3rd-largest of them by population served. Its population served is about 8.6 times the county average of 1,527 people per system, and accounts for 6.2% of the 213,824 people reported by systems filed under the county. Across Idaho, the 1,961 active systems average 899 people each. Nationally, the average active community water system reports serving 6,703 people, so City of Middleton 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. Idaho has 765 active community water systems, 39% of the state's 1,961 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,861 Idaho systems (95%) list groundwater as their primary source.
Who owns and regulates City of Middleton?
EPA lists City of Middleton as owned by a local government. The ID state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 16 of the 140 active systems in Canyon County (11%) are also owned by a local government.
Does City of Middleton have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in December 2025. The violations listed here began between April 2009 and December 2025. By type: 11 monitoring and reporting and 1 monitoring. The contaminant or rule involved most often is Chlorine (6 of them). EPA lists 10 as archived, 1 as unaddressed and 1 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. 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 |
|---|---|---|---|---|
| 2025-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2018-05-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Archived |
| 2016-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Archived |
| 2016-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Archived |
| 2016-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Archived |
| 2016-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Archived |
| 2016-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Archived |
| 2009-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | No | Archived |
| 2009-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,1-Trichloroethanecode 2981 | No | Archived |
| 2009-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dibromo-3-chloropropane (DBCP)code 2931 | No | Archived |
| 2009-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Trichloroethylenecode 2984 | No | Archived |
The 12 most recent 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.
City of Middleton: frequently asked questions
Who runs City of Middleton?
City of Middleton (PWSID ID3140074) is a community water system owned by a local government. It is regulated by the ID state drinking water program.
How many people does City of Middleton serve?
City of Middleton reports serving 13,190 people through 5,135 service connections in Canyon County, Idaho.
Where does City of Middleton 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 City of Middleton have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in December 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 City of Middleton'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. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in December 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the ID state drinking water program.
Where can I find City of Middleton's water quality report?
As a community water system, City of Middleton 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 Canyon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Nampa City of | Canyon | 100,200 | Community | Groundwater |
| Caldwell City of | Canyon | 74,000 | Community | Groundwater |
| Parma City of | Canyon | 2,250 | Community | Groundwater |
| Wilder City of | Canyon | 1,690 | Community | Groundwater |
| Caldwell Housing Authority | Canyon | 1,100 | Community | Groundwater |
| Greenleaf City of | Canyon | 846 | Community | Groundwater |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Middleton City of, PWSID ID3140074, Idaho”, https://aquacensus.com/water-systems/idaho/middleton-city-of-id3140074 (data as of October 1, 2026).