Public water system · MT0001748
ActiveCuster School Dist No 15
At a glance
Custer School Dist No 15 (PWSID MT0001748) is an active non-transient non-community water system in Yellowstone County, Montana. It reports serving 100 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as owned by a state government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
100
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Custer School Dist No 15 compare with other water systems in Yellowstone County?
By EPA's size categories, Custer School Dist No 15 is a very small system (500 people or fewer). Yellowstone County has 119 active public water systems. Its population served is well below the county average of 1,422 people per system, and accounts for less than 0.1% of the 169,240 people reported by systems filed under the county. Across Montana, the 2,378 active systems average 489 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Custer School Dist No 15 is well below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Montana has 319 active non-transient non-community water systems, 13% of the state's 2,378 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,994 Montana systems (84%) list groundwater as their primary source.
Who owns and regulates Custer School Dist No 15?
EPA lists Custer School Dist No 15 as owned by a state government. The MT state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 6 of the 119 active systems in Yellowstone County (5%) are also owned by a state government.
Does Custer School Dist No 15 have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2024. The violations listed here began between July 2016 and October 2024. By type: 9 monitoring and reporting, 2 monitoring and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Lead and Copper Rule (6 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 |
|---|---|---|---|---|
| 2024-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2022-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2021-09-29 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2020-07-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2019-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2018-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2017-12-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2016-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2016-07-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | 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.
Custer School Dist No 15: frequently asked questions
Who runs Custer School Dist No 15?
Custer School Dist No 15 (PWSID MT0001748) is a non-transient non-community water system owned by a state government. It is regulated by the MT state drinking water program.
How many people does Custer School Dist No 15 serve?
Custer School Dist No 15 reports serving 100 people through 1 service connection in Yellowstone County, Montana.
Where does Custer School Dist No 15 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 Custer School Dist No 15 have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 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 Custer School Dist No 15'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, one is health-based, and the most recent began in October 2024. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Custer School Dist No 15's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Custer School Dist No 15 is a non-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 Yellowstone County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Billings City of | Yellowstone | 114,000 | Community | Surface water |
| Billings Heights Co Water Dist of | Yellowstone | 12,000 | Community | Purchased surface water |
| Laurel Municipal Water System | Yellowstone | 6,339 | Community | Surface water |
| Lockwood Water and Sewer District | Yellowstone | 5,900 | Community | Surface water |
| Rocky Mountain College | Yellowstone | 5,700 | Non-transient non-community | Purchased surface water |
| Montana State University Billings | Yellowstone | 2,999 | Non-transient non-community | Purchased surface water |
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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, “Custer School Dist No 15, PWSID MT0001748, Montana”, https://aquacensus.com/water-systems/montana/custer-school-dist-no-15-mt0001748 (data as of October 1, 2026).