Systems reaching a study comparison level
3.7%2 of 54 active community water systems with complete monitoring
All 54 systems had complete monitoring. 2 reached at least one study comparison level; 52 did not. “Study comparison level” means the dated EPA technical cutoff used in this January 2026 research release. It does not determine household exposure, health risk, or current legal compliance.
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ZIP codes are used only to route visitors to public water systems that reported serving them. Confirm the actual provider using a water bill or utility record.
Compound summary
System counts in Idaho
Each count shows how many included water systems reached the named study level.
| Study comparison | Systems reaching level | Water systems included | Percent |
|---|---|---|---|
| PFOA: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 1 | 54 | 1.9% |
| PFOS: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 2 | 54 | 3.7% |
| PFHxS: study level 15 ppt (April 2024 EPA level: 10 ppt) | 1 | 54 | 1.9% |
| PFNA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 1 | 54 | 1.9% |
| HFPO-DA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 54 | 0.0% |
| Hazard Index: study level 1.5 with at least two detected components (April 2024 EPA level: 1) | 2 | 54 | 3.7% |
System directory
Community water systems with complete monitoring
Each PWSID appears once, preventing double counting across ZIP associations.
| Public water system | PWSID | Population served | Primary source | Sampling locations | Study comparison |
|---|---|---|---|---|---|
| AMERICAN FALLS CITY OF | ID6390001 | 4,863 | Ground water | 6 | Below the study levels |
| AMMON CITY OF | ID7100004 | 17,338 | Ground water | 4 | Below the study levels |
| AVONDALE IRRIGATION DIST | ID1280008 | 8,785 | Ground water | 4 | Below the study levels |
| BLACKFOOT CITY OF | ID6060007 | 13,224 | Ground water | 7 | Below the study levels |
| BUHL CITY OF | ID5420007 | 4,518 | Ground water | 5 | Below the study levels |
| BURLEY WATER DEPT | ID5160008 | 10,345 | Ground water | 5 | Below the study levels |
| CALDWELL CITY OF | ID3140013 | 74,000 | Ground water | 15 | Below the study levels |
| CAPITOL WATER CORP | ID4010022 | 9,000 | Ground water | 4 | Reached a study level |
| CHUBBUCK CITY OF | ID6030008 | 15,842 | Ground water | 5 | Below the study levels |
| COEUR D ALENE CITY OF | ID1280053 | 54,115 | Ground water | 11 | Below the study levels |
| COUGAR BAY WATER ASSOCIATION | ID1280309 | 230 | Ground water | 2 | Below the study levels |
| EAGLE, CITY OF (EASTERN ZONE) | ID4010201 | 3,702 | Ground water | 2 | Below the study levels |
| EAGLE, CITY OF (WESTERN ZONE) | ID4010222 | 6,108 | Ground water | 3 | Below the study levels |
| EAST GREENACRES IRRIGATION DIST | ID1280064 | 11,165 | Ground water | 3 | Below the study levels |
| FALLS WATER COMPANY INC | ID7100030 | 22,650 | Ground water | 7 | Below the study levels |
| FRUITLAND CITY OF | ID3380005 | 7,458 | Surface water | 1 | Below the study levels |
| GARDEN CITY WATER AND SEWER SYSTEM | ID4010066 | 12,500 | Ground water | 8 | Reached a study level |
| GRANGEVILLE WATER DEPT | ID2250023 | 3,151 | Ground water | 5 | Below the study levels |
| HAILEY WATER AND SEWER | ID5070022 | 8,000 | Ground water | 5 | Below the study levels |
| HAYDEN LAKE IRRIGATION DIST | ID1280087 | 9,375 | Ground water | 6 | Below the study levels |
| HEYBURN CITY OF | ID5340006 | 3,000 | Ground water | 3 | Below the study levels |
| IDAHO FALLS CITY OF | ID7100039 | 69,450 | Ground water | 15 | Below the study levels |
| KANIKSU SHORES ESTATES | ID1090065 | 93 | Ground water | 1 | Below the study levels |
| KETCHUM CITY OF | ID5070028 | 3,555 | Ground water | 6 | Below the study levels |
| KOOSKIA WATER DEPT | ID2250032 | 607 | Ground water | 2 | Below the study levels |
| KUNA CITY OF | ID4010085 | 32,038 | Ground water | 5 | Below the study levels |
| LEWISTON CITY OF | ID2350014 | 15,001 | Surface water | 6 | Below the study levels |
| LEWISTON ORCHARDS IRRIGATION DIST | ID2350015 | 20,000 | Ground water | 2 | Below the study levels |
| MCCALL CITY OF | ID4430033 | 4,423 | Surface water | 1 | Below the study levels |
| MERIDIAN WATER DEPT | ID4010097 | 147,340 | Ground water | 24 | Below the study levels |
| MIDDLETON CITY OF | ID3140074 | 13,190 | Ground water | 7 | Below the study levels |
| MORELAND COUNTRY COURT | ID6060049 | 60 | Ground water | 2 | Below the study levels |
| MOSCOW WATER DEPT | ID2290023 | 26,000 | Ground water | 5 | Below the study levels |
| MOUNTAIN HOME AIR FORCE BASE | ID4200054 | 7,500 | Ground water | 3 | Below the study levels |
| MOUNTAIN HOME CITY OF | ID4200032 | 14,651 | Ground water | 9 | Below the study levels |
| NAMPA CITY OF | ID3140080 | 100,200 | Ground water | 13 | Below the study levels |
| PAYETTE CITY OF | ID3380009 | 8,127 | Ground water | 7 | Below the study levels |
| PIERCE CITY OF | ID2180027 | 467 | Surface water | 1 | Below the study levels |
| POCATELLO CITY OF | ID6030043 | 58,231 | Ground water | 6 | Below the study levels |
| POST FALLS CITY OF | ID1280147 | 20,285 | Ground water | 9 | Below the study levels |
| POTLATCH CITY OF | ID2290030 | 812 | Ground water | 3 | Below the study levels |
| PRESTON CITY OF | ID6210014 | 5,591 | Ground water | 1 | Below the study levels |
| RATHDRUM CITY OF | ID1280152 | 10,358 | Ground water | 5 | Below the study levels |
| REXBURG CITY OF | ID7330022 | 40,695 | Ground water | 4 | Below the study levels |
| RIGBY CITY OF | ID7260032 | 5,400 | Ground water | 5 | Below the study levels |
| ROSS POINT WATER DIST | ID1280163 | 8,965 | Ground water | 5 | Below the study levels |
| RUPERT CITY OF | ID5340017 | 5,796 | Ground water | 3 | Below the study levels |
| SANDPOINT PUBLIC WORKS DEPT | ID1090121 | 12,284 | Surface water | 2 | Below the study levels |
| SHELLEY CITY OF | ID6060071 | 4,409 | Ground water | 4 | Below the study levels |
| ST ANTHONY | ID7220067 | 3,606 | Ground water | 2 | Below the study levels |
| STAR SEWER AND WATER DIST WATER SYSTEM | ID4010220 | 14,000 | Ground water | 4 | Below the study levels |
| UNIVERSITY OF IDAHO | ID2290042 | 8,589 | Ground water | 2 | Below the study levels |
| Veolia Water ID | ID4010016 | 264,978 | Surface water | 10 | Below the study levels |
| WEISER CITY OF | ID3440011 | 5,630 | Surface water | 1 | Below the study levels |
How the count works
What is included
Each active community water system with complete monitoring is counted once, even if it is linked with several ZIP codes. Private wells are excluded, and UCMR 5 did not comprehensively monitor every small system. This page does not apply Idaho's state-specific standards or determine compliance. Use the official state or territory drinking-water program for current regulatory information.