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 D.

Data sources: EPA SDWIS EPA ECHO EWG Tap Water Database Utility CCRs ⓘ How did we get these ratings?
State average grade
D
65/100
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.

BOISE
F 264,978
Boise
C 235,000
CALDWELL
D 74,000
COEUR D ALENE
D 54,115
IDAHO FALLS
D 69,450
MERIDIAN
D 147,340
NAMPA
D 100,200
POCATELLO
C 58,231
TWIN FALLS
D 56,121

Grade distribution

A
0 (0%)
B
0 (0%)
C
5 (56%)
D
4 (44%)
F
0 (0%)

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 74 C
#2 POCATELLO CITY OF POCATELLO 58,231 72 C
#3 COEUR D ALENE CITY OF COEUR D ALENE 54,115 67 C
#4 CALDWELL CITY OF CALDWELL 74,000 66 C
#5 MERIDIAN WATER DEPT MERIDIAN 147,340 65 C
#6 IDAHO FALLS CITY OF IDAHO FALLS 69,450 63 D
#7 NAMPA CITY OF NAMPA 100,200 60 D
#8 TWIN FALLS CITY OF TWIN FALLS 56,121 60 D
#9 VEOLIA WATER IDAHO BOISE 264,978 59 D