Public water system · MT0003509
ActiveGranite Water Works
At a glance
Granite Water Works (PWSID MT0003509) is an active non-transient non-community water system in Granite County, Montana. It reports serving 27 people through 1 service connection. 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 January 2005.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
27
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Granite Water Works compare with other water systems in Granite County?
By EPA's size categories, Granite Water Works is a very small system (500 people or fewer). Granite County has 21 active public water systems. Its population served is well below the county average of 380 people per system, and accounts for 0.3% of the 7,984 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 Granite Water Works 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 Granite Water Works?
EPA lists Granite Water Works as privately owned. 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. 12 of the 21 active systems in Granite County (57%) are also privately owned.
Does Granite Water Works have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2005. The violations listed here began between January 2005 and January 2005. By type: 12 monitoring and reporting. The contaminants or rules involved are Nitrate-Nitrite, 1,2,4-Trichlorobenzene, cis-1,2-Dichloroethylene and Xylenes, Total. EPA lists 11 as resolved and 1 as archived. 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. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2,4-Trichlorobenzenecode 2378 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | cis-1,2-Dichloroethylenecode 2380 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Xylenes, Totalcode 2955 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | o-Dichlorobenzenecode 2968 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | p-Dichlorobenzenecode 2969 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Thalliumcode 1085 | No | Archived |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2-Dichloroethanecode 2980 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | 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.
Granite Water Works: frequently asked questions
Who runs Granite Water Works?
Granite Water Works (PWSID MT0003509) is a non-transient non-community water system privately owned. It is regulated by the MT state drinking water program.
How many people does Granite Water Works serve?
Granite Water Works reports serving 27 people through 1 service connection in Granite County, Montana.
Where does Granite Water Works 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 Granite Water Works 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 January 2005. 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 Granite Water Works' 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 January 2005. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Granite Water Works' water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Granite Water Works 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 Granite County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Bearmouth Rest Stop Eastbound | Granite | 2,000 | Transient non-community | Groundwater |
| Bearmouth Rest Stop Westbound | Granite | 2,000 | Transient non-community | Groundwater |
| Philipsburg Town of | Granite | 1,360 | Community | Surface water |
| Fics Kwik Six | Granite | 405 | Transient non-community | Groundwater |
| Discovery Ski Area | Granite | 401 | Transient non-community | Groundwater |
| Parkers | Granite | 256 | Transient non-community | Groundwater |
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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, “Granite Water Works, PWSID MT0003509, Montana”, https://aquacensus.com/water-systems/montana/granite-water-works-mt0003509 (data as of October 1, 2026).