Idaho vs Washington: Whose Tap Water Is Cleaner?
Tap Water Quality in Idaho (81.7/100) vs Washington (85.6/100) — a 5% gap between neighbors, explained with July 2026 data.
Idaho and Washington share a border, but for tap water quality they don't share much else: Idaho averages 81.7/100 (rank #32 of 51) and Washington averages 85.6/100 (rank #16) as of July 2026 — a 5% gap between neighbors.
| Idaho | Washington | U.S. benchmark | |
|---|---|---|---|
| Quality score | 81.7/100 | 85.6/100 | 84.5/100 |
| Violations per water system | 2.6 | 1.8 | 2.5 |
Idaho in context
Idaho lands mid-pack for tap water quality: a score of 81.7/100 ranks #32 of 51, though its water systems averaged 2.6 health-based violations each in 2024, worse than the U.S. average of 2.5.
Washington in context
Washington lands mid-pack for tap water quality: a score of 85.6/100 ranks #16 of 51, and its water systems averaged 1.8 health-based violations each in 2024 — better than the U.S. average of 2.5.
Full local breakdowns: Idaho · Washington · all states ranked.
Averages describe states, not your faucet. A certified home water test screens for lead, nitrates, bacteria and dozens of other contaminants — the same categories EPA regulates.
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