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Community Water System · PWS MT0002005

Ten Mile and Pleasant Valley Wua

Helena, Montana 59604 - drinking water served from groundwater sources to 750 people, tracked in EPA SDWIS and UCMR5.

750
People served
460
EPA violations
8
Health-based
Untested
UCMR5 result

The verdict

EPA records 460 drinking-water violations at Ten Mile and Pleasant Valley Wua, 2% of them health-based - above the Montana per-system average.

460
Total EPA violations on record
2%
Health-based (MCL / treatment failure)
750
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Ten Mile and Pleasant Valley Wua

Ten Mile and Pleasant Valley Wua is a private-owned community water system that delivers drinking water to 750 residents in Helena, Montana (Lewis and Clark County) through 310 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 460 total violations for this system , of which 8 (2%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 429 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Lead and Copper Rule, recorded in 39 violations (MR). 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, 28 of 45 UCMR5-tested systems have reported PFAS detections (62.2%).

Ten Mile and Pleasant Valley Wua's 460 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
750
Total Violations
460
Health-Based Violations
8
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
310
County
Lewis and Clark
School/Daycare
No
MCL Violations
5
Monitoring Violations
429
Treatment Tech Violations
3

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Lead and Copper Rule MR 39 2024
Consumer Confidence Rule Other 19 2023
Thallium, Total MR 9 2011
1,2,4-Trichlorobenzene MR 9 2021
Xylenes, Total MR 9 2021
Vinyl chloride MR 9 2021
trans-1,2-Dichloroethylene MR 9 2021
1,1,1-Trichloroethane MR 9 2021
Carbon tetrachloride MR 9 2021
1,2-Dichloropropane MR 9 2021
Trichloroethylene MR 9 2021
1,1,2-Trichloroethane MR 9 2021
Tetrachloroethylene MR 9 2021
Ethylbenzene MR 9 2021
Styrene MR 9 2021
E. COLI MR 9 2014
cis-1,2-Dichloroethylene MR 9 2021
DICHLOROMETHANE MR 9 2021
o-Dichlorobenzene MR 9 2021
1,1-Dichloroethylene MR 9 2021
CHLOROBENZENE MR 9 2021
Benzene MR 9 2021
p-Dichlorobenzene MR 9 2021
1,2-Dichloroethane MR 9 2021
Toluene MR 9 2021
2,4,5-TP MR 8 2011
Arsenic MR 7 2011
Fluoride MR 6 2011
Mercury MR 6 2011
Dalapon MR 6 2011

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 Ten Mile and Pleasant Valley Wua.

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 MT0002005 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
2024 Lead and Copper Rule MR 39 SDWIS / MT0002005 / 5000
2024 Lead and Copper Rule TT 3 SDWIS / MT0002005 / 5000
2023 Consumer Confidence Rule Other 19 SDWIS / MT0002005 / 7000
2021 1,2,4-Trichlorobenzene MR 9 SDWIS / MT0002005 / 2378
2021 Xylenes, Total MR 9 SDWIS / MT0002005 / 2955
2021 Vinyl chloride MR 9 SDWIS / MT0002005 / 2976
2021 trans-1,2-Dichloroethylene MR 9 SDWIS / MT0002005 / 2979
2021 1,1,1-Trichloroethane MR 9 SDWIS / MT0002005 / 2981
2021 Carbon tetrachloride MR 9 SDWIS / MT0002005 / 2982
2021 1,2-Dichloropropane MR 9 SDWIS / MT0002005 / 2983
2021 Trichloroethylene MR 9 SDWIS / MT0002005 / 2984
2021 1,1,2-Trichloroethane MR 9 SDWIS / MT0002005 / 2985
2021 Tetrachloroethylene MR 9 SDWIS / MT0002005 / 2987
2021 Ethylbenzene MR 9 SDWIS / MT0002005 / 2992
2021 Styrene MR 9 SDWIS / MT0002005 / 2996

How Ten Mile and Pleasant Valley Wua Compares

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

Metric Ten Mile and Pleasant Valley Wua Montana avg Federal benchmark
Total violations 460 131.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 8 11.5 Indicates a contaminant exceeded a federal MCL
PFAS detection None 62.2% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 750 492 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 Ten Mile and Pleasant Valley Wua water safe to drink?
Ten Mile and Pleasant Valley Wua (PWS ID: MT0002005) has 460 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 750 people using Groundwater sources.
How many people does Ten Mile and Pleasant Valley Wua serve?
Ten Mile and Pleasant Valley Wua serves 750 people in Helena, Montana. It is a Private-owned system using Groundwater water sources with 310 service connections.
What type of violations does Ten Mile and Pleasant Valley Wua have?
Ten Mile and Pleasant Valley Wua has 460 total violations: 8 health-based violations (MCL exceedances or treatment failures), 429 monitoring/reporting violations, and 3 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Ten Mile and Pleasant Valley Wua water?
No PFAS testing data is available for Ten Mile and Pleasant Valley Wua under the EPA's UCMR5 monitoring program.
What water source does Ten Mile and Pleasant Valley Wua use?
Ten Mile and Pleasant Valley Wua 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.
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.