Public water system · MT0004368
ActiveRyans Lot
At a glance
Ryans Lot (PWSID MT0004368) is an active community water system in Missoula County, Montana. It reports serving 34 people through 15 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, one is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
34
Service connections
15
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Ryans Lot compare with other water systems in Missoula County?
By EPA's size categories, Ryans Lot is a very small system (500 people or fewer). Missoula County has 244 active public water systems. Its population served is well below the county average of 576 people per system, and accounts for less than 0.1% of the 140,505 people reported by systems filed under the county. Across Montana, the 2,378 active systems average 489 people each. Nationally, the average active community water system reports serving 6,703 people, so Ryans Lot is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Montana has 853 active community water systems, 36% 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 Ryans Lot?
EPA lists Ryans Lot 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. 201 of the 244 active systems in Missoula County (82%) are also privately owned.
Does Ryans Lot have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in July 2025. The violations listed here began between July 2019 and July 2025. By type: 6 monitoring and reporting, 5 public notice, recordkeeping or other and 1 required treatment not met. The contaminant or rule involved most often is Groundwater Rule (6 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2024-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-08-30 | Required treatment not metFailure To Address Deficiency · code 45 | Groundwater Rulecode 0700 | Yes | Resolved |
| 2023-06-01 | Public notice, recordkeeping or otherFailure to Consult with State · code 20 | Groundwater Rulecode 0700 | No | Resolved |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2022-06-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2022-05-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2021-07-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2021-05-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2020-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2019-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | 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.
Ryans Lot: frequently asked questions
Who runs Ryans Lot?
Ryans Lot (PWSID MT0004368) is a community water system privately owned. It is regulated by the MT state drinking water program.
How many people does Ryans Lot serve?
Ryans Lot reports serving 34 people through 15 service connections in Missoula County, Montana.
Where does Ryans Lot 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 Ryans Lot 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 July 2025. 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 Ryans Lot'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 July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the MT state drinking water program.
Where can I find Ryans Lot's water quality report?
As a community water system, Ryans Lot must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Missoula County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Missoula Water | Missoula | 68,200 | Community | Groundwater |
| University of Montana | Missoula | 15,000 | Non-transient non-community | Purchased groundwater |
| Lolo Water and Sewer Dist | Missoula | 3,315 | Community | Groundwater |
| Town Pump Bonner 1 | Missoula | 2,460 | Non-transient non-community | Groundwater |
| Clearwater Junction Rest Area | Missoula | 2,002 | Transient non-community | Groundwater |
| Seeley Lake Water District | Missoula | 1,575 | 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, “Ryans Lot, PWSID MT0004368, Montana”, https://aquacensus.com/water-systems/montana/ryans-lot-mt0004368 (data as of October 1, 2026).