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Public water system · ID4200076

Active

Key Mart Corner

At a glance

Key Mart Corner (PWSID ID4200076) is an active transient non-community water system in Elmore County, Idaho. It reports serving 50 people through 5 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, none is health-based, and the most recent began in November 2024.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

50

Service connections

5

Primary source

GW

Groundwater

System type

TNCWS

Transient non-community water system

System record

PWSIDID4200076
System typeTransient non-community water system
Activity statusActive
Population served50
Service connections5
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyID state drinking water program
City served—
StateIdaho
ZIP—
CountyElmore County

How does Key Mart Corner compare with other water systems in Elmore County?

By EPA's size categories, Key Mart Corner is a very small system (500 people or fewer). Elmore County has 44 active public water systems. Its population served is well below the county average of 607 people per system, and accounts for 0.2% of the 26,726 people reported by systems filed under the county. Across Idaho, the 1,961 active systems average 899 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Key Mart Corner is about 65% below that figure.

What does “transient non-community water system” mean?

A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. Idaho has 954 active transient non-community water systems, 49% 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 Key Mart Corner?

EPA lists Key Mart Corner 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. 39 of the 44 active systems in Elmore County (89%) are also privately owned.

Does Key Mart Corner have drinking water violations?

Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in November 2024. The violations listed here began between July 2016 and November 2024. By type: 7 monitoring and 5 monitoring and reporting. The contaminant or rule involved most often is Revised Total Coliform Rule (7 of them). EPA lists 12 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.

BeganViolationContaminant or ruleHealth-basedStatus
2024-11-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2024-08-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2024-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
2023-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
2021-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
2020-11-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2020-09-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2020-07-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2018-07-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2018-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
2017-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
2016-07-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved

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.

Key Mart Corner: frequently asked questions

Who runs Key Mart Corner?

Key Mart Corner (PWSID ID4200076) is a transient non-community water system privately owned. It is regulated by the ID state drinking water program.

How many people does Key Mart Corner serve?

Key Mart Corner reports serving 50 people through 5 service connections in Elmore County, Idaho.

Where does Key Mart Corner 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 Key Mart Corner 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 November 2024. 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 Key Mart Corner'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 November 2024. For current results, consult EPA ECHO, or the ID state drinking water program.

Where can I find Key Mart Corner's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. Key Mart Corner is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.

Other water systems in Elmore County

Water systemCountyPopulation servedTypeSource
Mountain Home, City ofElmore14,651CommunityGroundwater
Mountain Home Air Force BaseElmore7,500CommunityGroundwater
Glenns Ferry City ofElmore1,282CommunitySurface water
Mellen Subd Water DistElmore250CommunityPurchased groundwater
Trinity Estates Water Users AssnElmore250CommunityGroundwater
Canyon Creek Mobile Home ParkElmore243CommunityGroundwater

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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, “Key Mart Corner, PWSID ID4200076, Idaho”, https://aquacensus.com/water-systems/idaho/key-mart-corner-id4200076 (data as of October 1, 2026).