PlainWater
States → Montana

Community Water System · PWS MT0004368

Ryans Lot

Hermosa Beach, Montana 90254 - drinking water served from groundwater sources to 34 people, tracked in EPA SDWIS and UCMR5.

34
People served
788
EPA violations
80
Health-based
Untested
UCMR5 result

The verdict

EPA records 788 drinking-water violations at Ryans Lot, 10% of them health-based - above the Montana per-system average.

788
Total EPA violations on record
10%
Health-based (MCL / treatment failure)
34
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Ryans Lot

Ryans Lot is a private-owned community water system that delivers drinking water to 34 residents in Hermosa Beach, Montana (Missoula County) through 15 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 788 total violations for this system , of which 80 (10%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 677 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 64 violations (MCL, health-based). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Montana, EPA tracks 2,263 public water systems serving 1,112,267 people, with 297,270 cumulative violations and 25,922 health-based violations on record. About 95% of systems in the state carry at least one violation, and state-wide the average per system is 131.4 violations. Statewide, 5 of 45 UCMR5-tested systems have reported PFAS detections (11.1%).

Ryans Lot's 788 violations sit above the Montana average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
34
Total Violations
788
Health-Based Violations
80
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
15
County
Missoula
School/Daycare
No
MCL Violations
64
Monitoring Violations
677
Treatment Tech Violations
16

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 64 2009
Groundwater Rule MR 29 2022
Consumer Confidence Rule Other 20 2025
Benzene MR 18 2005
Toluene MR 18 2005
Ethylbenzene MR 18 2005
Styrene MR 18 2005
1,2,4-Trichlorobenzene MR 18 2005
Xylenes, Total MR 18 2005
o-Dichlorobenzene MR 18 2005
1,2-Dichloroethane MR 18 2005
1,1,2-Trichloroethane MR 18 2005
DICHLOROMETHANE MR 18 2005
p-Dichlorobenzene MR 18 2005
Vinyl chloride MR 18 2005
1,1-Dichloroethylene MR 18 2005
trans-1,2-Dichloroethylene MR 18 2005
1,1,1-Trichloroethane MR 18 2005
1,2-Dichloropropane MR 18 2005
Tetrachloroethylene MR 18 2005
cis-1,2-Dichloroethylene MR 18 2005
Trichloroethylene MR 18 2005
CHLOROBENZENE MR 18 2005
Carbon tetrachloride MR 18 2005
Groundwater Rule TT 16 2023
Lead and Copper Rule MR 12 2014
TTHM MR 10 2017
Total Haloacetic Acids (HAA5) MR 10 2017
Groundwater Rule Other 8 2023
Coliform (TCR) MR 7 2006

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Ryans Lot.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID MT0004368 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Montana Drinking Water Authority

Montana's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find MT regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2025 Consumer Confidence Rule Other 20 SDWIS / MT0004368 / 7000
2023 Groundwater Rule TT 16 SDWIS / MT0004368 / 0700
2023 Groundwater Rule Other 8 SDWIS / MT0004368 / 0700
2023 Nitrate-Nitrite MR 6 SDWIS / MT0004368 / 1038
2022 Groundwater Rule MR 29 SDWIS / MT0004368 / 0700
2017 TTHM MR 10 SDWIS / MT0004368 / 2950
2017 Total Haloacetic Acids (HAA5) MR 10 SDWIS / MT0004368 / 2456
2014 Lead and Copper Rule MR 12 SDWIS / MT0004368 / 5000
2014 Chlorine MR 3 SDWIS / MT0004368 / 0999
2009 Coliform (TCR) MCL 64 SDWIS / MT0004368 / 3100
2006 Coliform (TCR) MR 7 SDWIS / MT0004368 / 3100
2005 Benzene MR 18 SDWIS / MT0004368 / 2990
2005 Toluene MR 18 SDWIS / MT0004368 / 2991
2005 Ethylbenzene MR 18 SDWIS / MT0004368 / 2992
2005 Styrene MR 18 SDWIS / MT0004368 / 2996

How Ryans Lot Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Ryans Lot Montana avg Federal benchmark
Total violations 788 131.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 80 11.5 Indicates a contaminant exceeded a federal MCL
PFAS detection None 11.1% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 34 492 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,263 regulated public water systems in Montana.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Ryans Lot water safe to drink? ▼
Ryans Lot (PWS ID: MT0004368) has 788 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 34 people using Groundwater sources.
How many people does Ryans Lot serve? ▼
Ryans Lot serves 34 people in Hermosa Beach, Montana. It is a Private-owned system using Groundwater water sources with 15 service connections.
What type of violations does Ryans Lot have? ▼
Ryans Lot has 788 total violations: 80 health-based violations (MCL exceedances or treatment failures), 677 monitoring/reporting violations, and 16 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Ryans Lot water? ▼
No PFAS testing data is available for Ryans Lot under the EPA's UCMR5 monitoring program.
What water source does Ryans Lot use? ▼
Ryans Lot uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.