State Hub
Idaho Water Quality
174
Utilities in database
1.5M
Residents served
0
With open violations
56
PFAS monitored
Quick Answer
Idaho public drinking water is served by 174 EPA-tracked water systems, providing service to approximately 1.5 million residents through public utilities. No open health-based violations are currently recorded across tracked systems in the EPA federal database. 56 systems have official PFAS monitoring records from the EPA UCMR 5 program (2023–2025). About 40% of ID residents use private wells, which fall outside federal utility compliance monitoring.
No open health-based violations are currently recorded in the EPA SDWIS database for Idaho's tracked water systems. Always verify with your utility's Consumer Confidence Report for annual test results.
Drinking Water in Idaho
Idaho has 174 community water systems serving approximately 1.5 million residents. Primary water sources include groundwater. The most commonly reported contaminants include arsenic, nitrates. 40% of Idaho residents rely on private wells. DEQ holds primary enforcement authority under the Safe Drinking Water Act.
Safest Large Utilities
Idaho systems with no open health violations serving 10,000+ residents.
Utilities in Idaho
126–150 of 174City of Greenleaf
ID3140041 · 846 served
Kootenai County Water Dist 1
ID1280106 · 843 served
Gem State - Spirit Lake East
ID1280176 · 843 served
E Shoshone County Water Dist Mullan
ID1400017 · 840 served
City of Oakley
ID5160035 · 821 served
City of Potlatch
ID2290030 · 812 served
Meadow Creek Property Owners Assn Inc
ID3020009 · 800 served
Hillsdale Estates Homeowners Assn
ID4010218 · 800 served
City of Mccammon
ID6030038 · 800 served
City of Inkom
ID6030025 · 792 served
Horseshoe Bend Water Supply
ID4080024 · 750 served
City of Teton
ID7220072 · 735 served
City of Clark Fork
ID1090018 · 730 served
Sagle Valley Water Dist
ID1090118 · 708 served
City of Roberts
ID7260035 · 680 served
3d Water Association
ID7100201 · 680 served
Cataldo Water Dist
ID1400012 · 680 served
Laclede Water Dist
ID1090073 · 668 served
City of Ririe
ID7260034 · 656 served
Desert View Estates Water Corp
ID4010042 · 650 served
City of Melba
ID3140070 · 648 served
Gem State - Bar Circle S Ranch
ID1280010 · 633 served
City of Downey
ID6030012 · 625 served
City of Juliaetta
ID2290018 · 624 served
Southside Water and Sewer Dist
ID1090131 · 615 served
Key Contaminant Concerns in Idaho
These contaminants appear most frequently in Idaho utility records or pose elevated risk in this region based on EPA data.
Nitrates
Nitrate (NO₃⁻) is a nitrogen-containing compound that forms naturally through the decomposition of organic matter. At elevated concentrations — almost always caused by human activity — nitrate is converted in the digestive system to nitrite, which then reacts with hemoglobin to form methemoglobin, a form of hemoglobin that cannot carry oxygen. In the body, nitrite also reacts with amines in food to form N-nitroso compounds (nitrosamines) — known carcinogens classified by the IARC as Group 2A (probable human carcinogens). The United States applies over 23 million tons of nitrogen fertilizer annually, making agricultural runoff the dominant source of nitrate contamination in U.S. groundwater.
EPA limit: 10 mg/L
Arsenic
Arsenic (As) occurs naturally in rock and soil, dissolving into groundwater through natural weathering processes. Inorganic arsenic — the form found in drinking water — is a known human carcinogen. The western United States has particularly arsenic-rich geological formations, but elevated levels have been found in 48 states. Arsenic is tasteless and odorless.
EPA limit: 10 ppb
City Water Reports in Idaho
Tap water quality pages for Idaho cities — violations, PFAS records, utility profiles, and official source links.
Idaho PFAS Watchlist — all utilities with official recordsIndependent Water Testing
Find a certified lab in Idaho
Utility compliance records show what water systems report to the EPA. An independent test from a certified laboratory confirms what's actually in your tap water. Idaho labs can test for PFAS, lead, nitrates, bacteria, and dozens of other contaminants.
Explore Water Quality in Idaho
City of Greenleaf
Violation history, PFAS records, and official source links
Kootenai County Water Dist 1
Violation history, PFAS records, and official source links
Gem State - Spirit Lake East
Violation history, PFAS records, and official source links
PFAS monitoring records — Idaho
56 water systems in Idaho with EPA UCMR 5 records
Lead in Idaho drinking water
State-specific lead data, violation utilities, and testing guidance
PFAS in Idaho drinking water
State-specific PFAS data, MCL context, and treatment options
Certified water testing labs in Idaho
Labs certified for PFAS (EPA 533/537.1), lead, and bacteria testing
Water treatment options
Reverse osmosis, activated carbon, and filtration guides with cost ranges
Data sources and methodology
How WaterUtilityReport.com sources and validates official EPA data
Common Questions About Idaho Drinking Water
Does Idaho drinking water have PFAS?
56 Idaho water systems have EPA UCMR 5 PFAS monitoring records (2023–2025)
Which Idaho water utilities have open violations?
Browse Idaho utility compliance records and violation history
How do I test my water in Idaho?
State-certified labs for PFAS (EPA 533/537.1), lead, nitrate, and bacteria testing
What treatment removes PFAS from ID tap water?
Reverse osmosis removes PFAS, lead, arsenic, and nitrates — cost, maintenance, and NSF certification explained
What do Idaho PFAS records tell me about my water?
EPA limits, health context, and what UCMR 5 detection above MRL means for your water
How is Idaho water quality data sourced here?
EPA SDWIS violations, UCMR 5 PFAS records, and CCR data — sources, accuracy notes, and limitations
Idaho Water FAQs
Data sources: Utility compliance and violation data from EPA SDWIS (Safe Drinking Water Information System). PFAS monitoring records from EPA UCMR 5 (Unregulated Contaminant Monitoring Rule 5, 2023–2025). Contaminant data from EPA and ATSDR public references. This page summarizes public records — it is not a compliance determination. Methodology →
Last updated: 2026-04-22