Idaho Water Quality
According to EPA Safe Drinking Water Information System (SDWIS), Idaho has 773 active community water systems in this extract. PlainEnviro's health-based slice lists 2,331 violation records across 50 systems with at least one such row. These are historical EPA registry counts, not a statewide drinkability score.
Health-based violation records for 773 community water systems in Idaho. Source: EPA Safe Drinking Water Information System (SDWIS).
Water Systems with Most Health-Based Records
| # | Water System | Health-Based Records | Health |
|---|---|---|---|
| 1 | MISSION CREEK WATER ASSN Bonners Ferry | 203 | Yes |
| 2 | ELK CITY WATER AND SEWER ASSN Elk City | 114 | Yes |
| 3 | MEADOW LARK COURT LLC Ammon | 89 | Yes |
| 4 | JULIAETTA CITY OF Juliaetta | 81 | Yes |
| 5 | CLEARWATER WATER DIST Clearwater | 69 | Yes |
| 6 | DRAKE SUBD Caldwell | 62 | Yes |
| 7 | CEDAR SPRINGS COMMUNITY WATER Sagle | 60 | Yes |
| 8 | BIA NORTH IDAHO Lapwai | 49 | Yes |
| 9 | MCCALL CITY OF Mccall | 36 | Yes |
| 10 | ASPEN RIDGE SUBD Island Park | 35 | Yes |
| 11 | KING HILL DOMESTIC WATER AND SEWER King Hill | 34 | Yes |
| 12 | FRUITLAND CITY OF Fruitland | 31 | Yes |
| 13 | FERNAN ESTATES CORPORATION Coeur D Alene | 29 | Yes |
| 14 | RED ROCK WATER LLC Lewiston | 29 | Yes |
| 15 | INDIAN VILLAGE Nampa | 29 | Yes |
| 16 | SHOTGUN CHEROKEE SUBD 5 Island Park | 28 | Yes |
| 17 | CASTLE MOUNTAIN CREEKS OWNERS ASSN Garden Valley | 27 | Yes |
| 18 | NEW HOPE SUBD Lenore | 25 | Yes |
| 19 | FILER WATER WORKS Filer | 23 | Yes |
| 20 | RAMSEY ESTATES Coeur D'alene | 22 | Yes |
| 21 | BELLEVUE CITY OF Bellevue | 22 | Yes |
| 22 | OAKLEY VALLEY WATER CORPORATION Oakley | 22 | Yes |
| 23 | ASHTON CITY OF Ashton | 22 | Yes |
| 24 | IDAHO YOUTH RANCH HANDS OF PROMISE Caldwell | 21 | Yes |
| 25 | COUNTRY COURT COMMUNITY Grangeville | 20 | Yes |
| 26 | RIVERBEND ESTATES American Falls | 20 | Yes |
| 27 | SALMON CITY OF Salmon | 20 | Yes |
| 28 | GARDEN VALLEY RANCHETTES HOMEOWNERS Garden Valley | 18 | Yes |
| 29 | HAMMETT HAVEN APARTMENTS Mountain Home | 18 | Yes |
| 30 | WAYSIDE ESTATES Heyburn | 18 | Yes |
| 31 | SHOTGUN NORTH Island Park | 18 | Yes |
| 32 | MOUNTAIN HOME AIR FORCE BASE Mountain Home Afb | 16 | Yes |
| 33 | EATON MOBILE HOME COURT Lewiston | 14 | Yes |
| 34 | IDAHO CITY WATER DEPT Idaho City | 14 | Yes |
| 35 | LITTLE BLACKTAIL RANCH WATER DISTRICT Athol | 13 | Yes |
| 36 | GOOSE CREEK RENTALS Indian Valley | 13 | Yes |
| 37 | TERRACE LAKES WATER COMPANY New Plymouth | 13 | Yes |
| 38 | BANIDA WATER AND SEWER DIST Preston | 13 | Yes |
| 39 | BEE LINE WATER ASSN INC Bonners Ferry | 12 | Yes |
| 40 | TWENTY MILE CREEK WATER ASSN Bonners Ferry | 12 | Yes |
| 41 | FRANKLIN DOMESTIC WATER USERS Boise | 12 | Yes |
| 42 | GREENHILLS ESTATES 3 Meridian | 12 | Yes |
| 43 | MEANDER POINT SUBD Twin Falls | 12 | Yes |
| 44 | SUNBEAM WATER Rockland | 12 | Yes |
| 45 | LODGE HAVEN WATER COMPANY Sandpoint | 11 | Yes |
| 46 | REUBENS CITY OF Reubens | 11 | Yes |
| 47 | ISLAND VILLAGE MOBILE HOME PARK Boise | 11 | Yes |
| 48 | CASSANDRA HILLS OWNERS ASSN St Maries | 10 | Yes |
| 49 | SUNNYRIDGE I SUBD Nampa | 10 | Yes |
| 50 | OHIO MATCH ESTATES Rathdrum | 9 | Yes |
Most Common Contaminants in Idaho
| Contaminant | Violations | Systems Affected |
|---|---|---|
| Groundwater Rule | 635 | 137 |
| Revised Total Coliform Rule | 290 | 96 |
| Combined Uranium | 227 | 9 |
| Nitrate | 221 | 13 |
| CARBON, TOTAL | 193 | 3 |
| Arsenic | 186 | 17 |
| Total Haloacetic Acids (HAA5) | 116 | 11 |
| LEAD AND COPPER RULE REVISIONS | 98 | 61 |
| Interim Enhanced Surface Water Treatment Rule | 90 | 9 |
| Surface Water Treatment Rule | 74 | 21 |
| Coliform (TCR) | 53 | 32 |
| Lead and Copper Rule | 40 | 23 |
| Gross Alpha, Excl. Radon and U | 37 | 5 |
| TTHM | 26 | 4 |
| Di(2-ethylhexyl) phthalate | 15 | 2 |
Cities with Water Quality Issues
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About This Data
Water quality data is from the EPA Safe Drinking Water Information System (SDWIS). Health-based violations include Maximum Contaminant Level (MCL) and Treatment Technique (TT) violations. Only community water systems (CWS) in Idaho are included.
Source: U.S. Environmental Protection Agency, SDWIS Federal Reporting Services
Read our methodology - how this data is sourced, computed, and verified.