Industrial context
Idaho's PFAS exposure is limited compared to more industrialized states, with documented impacts concentrated near Mountain Home Air Force Base and former Cold-War-era military fire-training sites.
By State · ID
PFAS in Idaho water
Based on EPA UCMR 5 testing of 41 public water systems with PFAS detected in Idaho.
See Idaho on the national heatmap Systems tested in state
41 With PFAS detected
41 Above EPA limits
3 (7%) State totals reflect systems with at least one PFAS detection in UCMR 5 (the canonical EPA dataset). The 6,151 national total includes ~123 additional systems in US territories and on tribal lands not browsable as state pages.
Most contaminated in Idaho
3 Idaho water systems tested above EPA PFAS limits. The most severe is GARDEN CITY WATER AND SEWER SYSTEM, where PFOS measured 28.2 ppt — 7.0× the federal limit.
State context
How PFAS shows up in Idaho
Regulatory stance
Idaho follows the federal EPA framework with no state-level PFAS MCL.
Notable sites
Mountain Home AFB is on the DoD's list of PFAS-contaminated installations.
Editorial summary compiled from public DoD, EPA, and state agency disclosures. Not a comprehensive site inventory — for the authoritative list of PFAS investigation locations in Idaho, consult your state environmental agency.
Most Commonly Detected PFAS in Idaho
Systems with detections · EPA UCMR 5 (2023–2025)
lithium 39 systems
PFPeA 6 systems
PFHxA 6 systems
PFBS 5 systems
PFHxS 4 systems
PFOS 3 systems
Check your Idaho ZIP code
Get specific results for your neighborhood's water utility.
Browse Idaho by city
7 citiesCity overviews aggregate every utility and ZIP code in the area. Don't see your city? Use the ZIP lookup above — every Idaho ZIP has a result.
Water Systems in Idaho (41)
| Water System ↕ | PWSID | PFAS Detected ↕ | Above MCL ↕ | Risk |
|---|---|---|---|---|
| CAPITOL WATER CORP Groundwater | ID4010022 | 8 | 3 | High Risk |
| GARDEN CITY WATER AND SEWER SYSTEM Groundwater | ID4010066 | 8 | 2 | High Risk |
| MERIDIAN WATER DEPT Groundwater | ID4010097 | 3 | 1 | High Risk |
| LEWISTON CITY OF Groundwater | ID2350014 | 4 | 0 | Low Level |
| MOUNTAIN HOME AIR FORCE BASE Groundwater | ID4200054 | 4 | 0 | Low Level |
| PAYETTE CITY OF Groundwater | ID3380009 | 3 | 0 | Low Level |
| RATHDRUM CITY OF Groundwater | ID1280152 | 2 | 0 | Low Level |
| SHELLEY CITY OF Groundwater | ID6060071 | 2 | 0 | Low Level |
| GRANGEVILLE WATER DEPT Groundwater | ID2250023 | 1 | 0 | Low Level |
| KOOSKIA WATER DEPT Groundwater | ID2250032 | 1 | 0 | Low Level |
| POTLATCH CITY OF Groundwater | ID2290030 | 1 | 0 | Low Level |
| LEWISTON ORCHARDS IRRIGATION DIST Groundwater | ID2350015 | 1 | 0 | Low Level |
| CALDWELL CITY OF Groundwater | ID3140013 | 1 | 0 | Low Level |
| MIDDLETON CITY OF Groundwater | ID3140074 | 1 | 0 | Low Level |
| NAMPA CITY OF Groundwater | ID3140080 | 1 | 0 | Low Level |
| EMMETT CITY OF Groundwater | ID3230012 | 1 | 0 | Low Level |
| WEISER CITY OF Surface Water | ID3440011 | 1 | 0 | Low Level |
| Veolia Water ID Groundwater | ID4010016 | 1 | 0 | Low Level |
| Veolia Eagle Groundwater | ID4010049 | 1 | 0 | Low Level |
| KUNA CITY OF Groundwater | ID4010085 | 1 | 0 | Low Level |
| EAGLE, CITY OF (EASTERN ZONE) Groundwater | ID4010201 | 1 | 0 | Low Level |
| STAR SEWER AND WATER DIST WATER SYSTEM Groundwater | ID4010220 | 1 | 0 | Low Level |
| EAGLE, CITY OF (WESTERN ZONE) Groundwater | ID4010222 | 1 | 0 | Low Level |
| KETCHUM CITY OF Groundwater | ID5070028 | 1 | 0 | Low Level |
| BURLEY WATER DEPT Groundwater | ID5160008 | 1 | 0 | Low Level |
| JEROME CITY OF Groundwater | ID5270011 | 1 | 0 | Low Level |
| HEYBURN CITY OF Groundwater | ID5340006 | 1 | 0 | Low Level |
| RUPERT CITY OF Groundwater | ID5340017 | 1 | 0 | Low Level |
| BUHL CITY OF Groundwater | ID5420007 | 1 | 0 | Low Level |
| TWIN FALLS CITY OF Groundwater | ID5420058 | 1 | 0 | Low Level |
| CHUBBUCK CITY OF Groundwater | ID6030008 | 1 | 0 | Low Level |
| POCATELLO CITY OF Groundwater | ID6030043 | 1 | 0 | Low Level |
| BLACKFOOT CITY OF Groundwater | ID6060007 | 1 | 0 | Low Level |
| MORELAND COUNTRY COURT Groundwater | ID6060049 | 1 | 0 | Low Level |
| AMERICAN FALLS CITY OF Groundwater | ID6390001 | 1 | 0 | Low Level |
| AMMON CITY OF Groundwater | ID7100004 | 1 | 0 | Low Level |
| FALLS WATER COMPANY INC Groundwater | ID7100030 | 1 | 0 | Low Level |
| IDAHO FALLS CITY OF Groundwater | ID7100039 | 1 | 0 | Low Level |
| ST ANTHONY Groundwater | ID7220067 | 1 | 0 | Low Level |
| RIGBY CITY OF Groundwater | ID7260032 | 1 | 0 | Low Level |
| REXBURG CITY OF Groundwater | ID7330022 | 1 | 0 | Low Level |
No water systems match your search. Try a different name or PWSID.
Click any row to see ZIP-level details. Click PWSID to see the full utility page.
Test your water
How to get your Idaho water tested for PFAS
EPA UCMR 5 tested 41 public water systems in Idaho — but at the utility entry point, not your tap. Aging pipes and indoor plumbing can change what reaches your home, and private wells aren't covered by UCMR 5 at all. To find out what's actually in your water, test it with a certified lab.
- 01 →
How PFAS water testing works
EPA Method 537.1 in plain English — what a certified lab actually measures
- 02 →
Order a certified mail-in test kit
PFAS mail-in kits from about $85 (Cyclopure, Tap Score)
- 03 →
On a private well in Idaho?
Wells aren't covered by EPA testing — your own testing guide
Idaho testing resources
- PFAS limits
- Idaho follows the federal EPA limits and is pursuing state primacy for the 2024 federal PFAS rule (monitoring by April 2027).
- State help
- Idaho Health & Welfare offers free private-well testing, but its panel does not include PFAS. Program details →
Compiled from official Idaho state sources. Programs and eligibility change — confirm current details with the agency.