Idaho Water Quality Ratings
TapWaterSafety has rated 9 public water systems in Idaho, serving a combined 1,059,435 residents. The statewide average grade is C.
State average grade
C
Total utilities rated
9
Population served
1,059,435
Most recent test
2024
🇪🇺 Would fail EU standards
2 of 9
Top water quality concerns in Idaho
- Arsenic significantly above health guideline
- Chromium (hexavalent) significantly above health guideline
- Haloacetic acids (HAA9) significantly above health guideline
- Total trihalomethanes (TTHMs) significantly above health guideline
- Dibromoacetic acid significantly above health guideline
Cities in Idaho
Browse tap water quality reports by city. Click any city to see its grade, what's in the water, and recommended filters.
Grade distribution
All rated utilities in Idaho
Sorted by score, highest first. Click any utility to see the full grade card.
| Rank | Utility | City | Population | Score | Grade |
|---|---|---|---|---|---|
| #1 | Boise Municipal Water System | Boise | 235,000 | 83 | B |
| #2 | COEUR D ALENE CITY OF | COEUR D ALENE | 54,115 | 79 | B |
| #3 | POCATELLO CITY OF | POCATELLO | 58,231 | 78 | B |
| #4 | MERIDIAN WATER DEPT | MERIDIAN | 147,340 | 77 | B |
| #5 | IDAHO FALLS CITY OF | IDAHO FALLS | 69,450 | 74 | C |
| #6 | CALDWELL CITY OF | CALDWELL | 74,000 | 73 | C |
| #7 | NAMPA CITY OF | NAMPA | 100,200 | 69 | C |
| #8 | VEOLIA WATER IDAHO | BOISE | 264,978 | 60 | D |
| #9 | TWIN FALLS CITY OF | TWIN FALLS | 56,121 | 57 | D |