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Public water system · MT0001820

Active

Lone Mountain Guest Ranch

At a glance

Lone Mountain Guest Ranch (PWSID MT0001820) is an active non-transient non-community water system in Gallatin County, Montana. It reports serving 75 people through 25 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 December 2024.

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

Population served

75

Service connections

25

Primary source

GW

Groundwater

System type

NTNCWS

Non-transient non-community water system

System record

PWSIDMT0001820
System typeNon-transient non-community water system
Activity statusActive
Population served75
Service connections25
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyMT state drinking water program
City servedBig Sky
StateMontana
ZIP—
CountyGallatin County

How does Lone Mountain Guest Ranch compare with other water systems in Gallatin County?

By EPA's size categories, Lone Mountain Guest Ranch is a very small system (500 people or fewer). Gallatin County has 207 active public water systems. Its population served is well below the county average of 713 people per system, and accounts for less than 0.1% of the 147,534 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 Lone Mountain Guest Ranch 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 Lone Mountain Guest Ranch?

EPA lists Lone Mountain Guest Ranch 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. 180 of the 207 active systems in Gallatin County (87%) are also privately owned.

Does Lone Mountain Guest Ranch have drinking water violations?

Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in December 2024. The violations listed here began between January 2020 and December 2024. By type: 12 monitoring and reporting. The contaminants or rules involved are Lead and Copper Rule, Groundwater Rule, Beryllium and Dinoseb. 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
2024-12-30Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved
2022-12-01Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31Groundwater Rulecode 0700NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Berylliumcode 1075NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Dinosebcode 2041NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Nickelcode 1036NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Antimonycode 1074NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Hexachlorobenzenecode 2274NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Xylenes, Totalcode 2955NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03cis-1,2-Dichloroethylenecode 2380NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Picloramcode 2040NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 03Mercurycode 1035NoResolved
2020-01-01Monitoring and reportingMonitoring, Regular · code 031,2,4-Trichlorobenzenecode 2378NoResolved

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.

Lone Mountain Guest Ranch: frequently asked questions

Who runs Lone Mountain Guest Ranch?

Lone Mountain Guest Ranch (PWSID MT0001820) is a non-transient non-community water system privately owned. It is regulated by the MT state drinking water program.

How many people does Lone Mountain Guest Ranch serve?

Lone Mountain Guest Ranch reports serving 75 people through 25 service connections in Gallatin County, Montana.

Where does Lone Mountain Guest Ranch 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 Lone Mountain Guest Ranch 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 December 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 Lone Mountain Guest Ranch'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 December 2024. For current results, consult EPA ECHO, or the MT state drinking water program.

Where can I find Lone Mountain Guest Ranch's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. Lone Mountain Guest Ranch 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 Gallatin County

Water systemCountyPopulation servedTypeSource
Bozeman City ofGallatin56,000CommunitySurface water
Montana State University BozemanGallatin19,200Non-transient non-communityPurchased surface water
Belgrade City ofGallatin10,460CommunityGroundwater
West Yellowstone Town ofGallatin9,899CommunityGroundwater
North Star Zoot WaterGallatin4,323CommunityGroundwater
River Rock County Water and Sewer DistGallatin4,200CommunityGroundwater

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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, “Lone Mountain Guest Ranch, PWSID MT0001820, Montana”, https://aquacensus.com/water-systems/montana/lone-mountain-guest-ranch-mt0001820 (data as of October 1, 2026).