County Water Quality Report

Ada County, Idaho

3 public water systems serving 647,318 residents

Data sources: EPA SDWIS EPA ECHO EWG Tap Water Database Utility CCRs ⓘ How did we get these ratings?
County average grade
D
66/100
Utilities rated 3
Population served 647,318
Most recent test 2024
🇪🇺 Would fail EU standards 2 of 3

Top water quality concerns in Ada County

  • Arsenic significantly above health guidelinein 3 of 3 utilities
  • Haloacetic acids (HAA9) significantly above health guidelinein 2 of 3 utilities
  • Haloacetic acids (HAA5) significantly above health guidelinein 1 of 3 utilities
  • Total trihalomethanes (TTHMs) significantly above health guidelinein 1 of 3 utilities

All utilities in Ada County

Click any utility for full grade card, contaminant data, and treatment plant contact info.

C
74/100

Boise Municipal Water System

Boise · 235,000 residents

Top concern: Arsenic significantly above health guideline

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C
65/100

MERIDIAN WATER DEPT

MERIDIAN · 147,340 residents

Top concern: Arsenic significantly above health guideline

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D
59/100

VEOLIA WATER IDAHO

BOISE · 264,978 residents

Top concern: Arsenic significantly above health guideline

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