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States → Idaho

Community Water System · PWS ID4200073

Mountain Sage

Boise, Idaho 83707 - drinking water served from groundwater sources to 65 people, tracked in EPA SDWIS and UCMR5.

65
People served
140
EPA violations
18
Health-based
Untested
UCMR5 result

The verdict

EPA records 140 drinking-water violations at Mountain Sage, 13% of them health-based - above the Idaho per-system average.

140
Total EPA violations on record
13%
Health-based (MCL / treatment failure)
65
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Mountain Sage

Mountain Sage is a private-owned community water system that delivers drinking water to 65 residents in Boise, Idaho (Elmore County) through 28 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 140 total violations for this system , of which 18 (13%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 112 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 Lead and Copper Rule, recorded in 14 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 Idaho, EPA tracks 2,005 public water systems serving 1,743,912 people, with 104,850 cumulative violations and 19,965 health-based violations on record. About 96% of systems in the state carry at least one violation, and state-wide the average per system is 52.3 violations. Statewide, 40 of 60 UCMR5-tested systems have reported PFAS detections (66.7%).

Mountain Sage's 140 violations sit above the Idaho 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
65
Total Violations
140
Health-Based Violations
18
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
28
County
Elmore
School/Daycare
No
MCL Violations
15
Monitoring Violations
112
Treatment Tech Violations
3

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Lead and Copper Rule MR 14 2016
Coliform (TCR) MCL 11 2015
E. COLI MR 9 2022
Coliform (TCR) MR 8 2015
Revised Total Coliform Rule MCL 4 2025
Public Notice Other 3 2025
LEAD AND COPPER RULE REVISIONS TT 3 2024
LEAD AND COPPER RULE REVISIONS RPT 3 2024
Revised Total Coliform Rule MON 3 2022
Groundwater Rule Other 3 2018
Benzene MR 2 2025
Carbon tetrachloride MR 2 2025
1,1-Dichloroethylene MR 2 2025
cis-1,2-Dichloroethylene MR 2 2025
trans-1,2-Dichloroethylene MR 2 2025
1,2-Dichloroethane MR 2 2025
Ethylbenzene MR 2 2025
CHLOROBENZENE MR 2 2025
Styrene MR 2 2025
1,1,1-Trichloroethane MR 2 2025
Xylenes, Total MR 2 2025
Dinoseb MR 2 2025
2,4-D MR 2 2025
Nitrate MR 2 2008
Picloram MR 2 2025
p-Dichlorobenzene MR 2 2025
Trichloroethylene MR 2 2025
Dalapon MR 2 2025
1,2-Dichloropropane MR 2 2025
o-Dichlorobenzene MR 2 2025

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 Mountain Sage.

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 ID4200073 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Idaho Drinking Water Authority

Idaho'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 ID 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 Revised Total Coliform Rule MCL 4 SDWIS / ID4200073 / 8000
2025 Public Notice Other 3 SDWIS / ID4200073 / 7500
2025 Benzene MR 2 SDWIS / ID4200073 / 2990
2025 Carbon tetrachloride MR 2 SDWIS / ID4200073 / 2982
2025 1,1-Dichloroethylene MR 2 SDWIS / ID4200073 / 2977
2025 cis-1,2-Dichloroethylene MR 2 SDWIS / ID4200073 / 2380
2025 trans-1,2-Dichloroethylene MR 2 SDWIS / ID4200073 / 2979
2025 1,2-Dichloroethane MR 2 SDWIS / ID4200073 / 2980
2025 Ethylbenzene MR 2 SDWIS / ID4200073 / 2992
2025 CHLOROBENZENE MR 2 SDWIS / ID4200073 / 2989
2025 Styrene MR 2 SDWIS / ID4200073 / 2996
2025 1,1,1-Trichloroethane MR 2 SDWIS / ID4200073 / 2981
2025 Xylenes, Total MR 2 SDWIS / ID4200073 / 2955
2025 Dinoseb MR 2 SDWIS / ID4200073 / 2041
2025 2,4-D MR 2 SDWIS / ID4200073 / 2105

How Mountain Sage Compares

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

Metric Mountain Sage Idaho avg Federal benchmark
Total violations 140 52.3 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 18 10 Indicates a contaminant exceeded a federal MCL
PFAS detection None 66.7% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 65 870 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,005 regulated public water systems in Idaho.

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 Mountain Sage water safe to drink? ▼
Mountain Sage (PWS ID: ID4200073) has 140 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 65 people using Groundwater sources.
How many people does Mountain Sage serve? ▼
Mountain Sage serves 65 people in Boise, Idaho. It is a Private-owned system using Groundwater water sources with 28 service connections.
What type of violations does Mountain Sage have? ▼
Mountain Sage has 140 total violations: 18 health-based violations (MCL exceedances or treatment failures), 112 monitoring/reporting violations, and 3 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Mountain Sage water? ▼
No PFAS testing data is available for Mountain Sage under the EPA's UCMR5 monitoring program.
What water source does Mountain Sage use? ▼
Mountain Sage 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.