Public water system · 083090302
ActiveDayton School
At a glance
Dayton School (PWSID 083090302) is an active non-transient non-community water system in Montana. It reports serving 74 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as Native American-owned. EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in April 2012.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
74
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Dayton School compare with other water systems in Montana?
By EPA's size categories, Dayton School is a very small system (500 people or fewer). 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 Dayton School 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 Dayton School?
EPA lists Dayton School as Native American-owned. The EPA Region 08 is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act.
Does Dayton School have drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in April 2012. The violations listed here began between July 2008 and April 2012. By type: 1 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 2 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2012-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 2 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.
Dayton School: frequently asked questions
Who runs Dayton School?
Dayton School (PWSID 083090302) is a non-transient non-community water system Native American-owned. It is regulated by the EPA Region 08.
How many people does Dayton School serve?
Dayton School reports serving 74 people through 1 service connection in Montana.
Where does Dayton School 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 Dayton School have any drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in April 2012. 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 Dayton School'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 2 violations for this system; 1 is health-based, and the most recent began in April 2012. For current results, consult EPA ECHO, or the EPA Region 08.
Where can I find Dayton School's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Dayton School 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 Montana
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Billings City of | Yellowstone | 114,000 | Community | Surface water |
| Missoula Water | Missoula | 68,200 | Community | Groundwater |
| Great Falls City of | Cascade | 60,000 | Community | Surface water |
| Bozeman City of | Gallatin | 56,000 | Community | Surface water |
| Butte Silverbow Water Dept | Silver Bow | 33,000 | Community | Surface water |
| Helena Water System | Lewis and Clark | 32,091 | Community | 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, “Dayton School, PWSID 083090302, Montana”, https://aquacensus.com/water-systems/montana/dayton-school-083090302 (data as of October 1, 2026).