Public water system · ID5070020
ActiveGreenhorn Subd
At a glance
Greenhorn Subd (PWSID ID5070020) is an active community water system in Blaine County, Idaho. It reports serving 75 people through 29 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
75
Service connections
29
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Greenhorn Subd compare with other water systems in Blaine County?
By EPA's size categories, Greenhorn Subd is a very small system (500 people or fewer). Blaine County has 43 active public water systems. Its population served is well below the county average of 552 people per system, and accounts for 0.3% of the 23,727 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 Greenhorn Subd 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. 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 Greenhorn Subd?
EPA lists Greenhorn Subd as privately owned. 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. 27 of the 43 active systems in Blaine County (63%) are also privately owned.
Does Greenhorn Subd have drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in July 2025. The violations listed here began between January 2020 and July 2025. By type: 6 monitoring and reporting, 4 contaminant level above the legal limit, 1 reporting and 1 monitoring. The contaminant or rule involved most often is Haloacetic acids (HAA5) (4 of them). EPA lists 11 as resolved and 1 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-07-02 | ReportingNotification, Known or Potential LSL · code 4H | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2024-07-01 | Monitoring and reportingInitial, Follow-up, or Routine Source Water M/R · code 56 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2023-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-08-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2023-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2022-07-01 | Monitoring and reportingInitial, Follow-up, or Routine Source Water M/R · code 56 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2020-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2020-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2020-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2020-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
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.
Greenhorn Subd: frequently asked questions
Who runs Greenhorn Subd?
Greenhorn Subd (PWSID ID5070020) is a community water system privately owned. It is regulated by the ID state drinking water program.
How many people does Greenhorn Subd serve?
Greenhorn Subd reports serving 75 people through 29 service connections in Blaine County, Idaho.
Where does Greenhorn Subd 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 Greenhorn Subd have any drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in July 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 Greenhorn Subd'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, 4 are health-based, and the most recent began in July 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 Greenhorn Subd's water quality report?
As a community water system, Greenhorn Subd 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 Blaine County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Hailey Water and Sewer | Blaine | 8,000 | Community | Groundwater |
| Ketchum City of | Blaine | 3,555 | Community | Groundwater |
| Sun Valley Water and Sewer Dist | Blaine | 3,400 | Community | Groundwater |
| Bellevue City of | Blaine | 2,747 | Community | Groundwater |
| Bald Mountain | Blaine | 1,000 | Transient non-community | Groundwater |
| Carey Water and Sewer | Blaine | 993 | 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, “Greenhorn Subd, PWSID ID5070020, Idaho”, https://aquacensus.com/water-systems/idaho/greenhorn-subd-id5070020 (data as of October 1, 2026).