Idaho County Water Quality Reports

Ada County, ID: 99 Health Violations — 72/100 (2026)

2026 report: Ada County, ID scores 72/100 (Grade B). 38 ZIP codes analyzed. 554 EPA violations found. Free report with contaminant data and filter picks.

Adams County, ID: Lead Above EPA Limits — 74/100 (2026)

2026 report: Adams County, ID scores 74/100 (Grade B). 5 ZIP codes analyzed. 7 EPA violations found. Lead above EPA limits. Free report with contaminant...

Bannock County, ID: 1 Health Violation — 79/100 (2026)

2026 report: Bannock County, ID scores 79/100 (Grade B). 11 ZIP codes analyzed. 15 EPA violations found. Free report with contaminant data and filter pi...

Bear Lake County, ID: 6 Violations — 69/100 (2026)

2026 report: Bear Lake County, ID scores 69/100 (Grade C). 9 ZIP codes analyzed. 6 EPA violations found. Free report with contaminant data and filter pi...

Benewah County, ID: 1 Health Violation — 54/100 (2026)

2026 report: Benewah County, ID scores 54/100 (Grade D). 5 ZIP codes analyzed. 17 EPA violations found. Free report with contaminant data and filter picks.

Bingham County, ID: 4 Health Violations — 71/100 (2026)

2026 report: Bingham County, ID scores 71/100 (Grade B). 9 ZIP codes analyzed. 24 EPA violations found. Free report with contaminant data and filter picks.

Blaine County, ID: 4 Health Violations — 60/100 (2026)

2026 report: Blaine County, ID scores 60/100 (Grade C). 7 ZIP codes analyzed. 38 EPA violations found. Free report with contaminant data and filter picks.

Boise County, ID: 5 Health Violations — 47/100 (2026)

2026 report: Boise County, ID scores 47/100 (Grade D). 8 ZIP codes analyzed. 23 EPA violations found. Free report with contaminant data and filter picks.

Bonner County, ID: 2 Health Violations — 57/100 (2026)

2026 report: Bonner County, ID scores 57/100 (Grade C). 15 ZIP codes analyzed. 19 EPA violations found. Free report with contaminant data and filter picks.

Bonneville County, ID: 32 Health Violations — 71/100 (2026)

2026 report: Bonneville County, ID scores 71/100 (Grade B). 13 ZIP codes analyzed. 97 EPA violations found. Free report with contaminant data and filter...

Boundary County, ID: 1 Health Violation — 50/100 (2026)

2026 report: Boundary County, ID scores 50/100 (Grade D). 5 ZIP codes analyzed. 6 EPA violations found. Free report with contaminant data and filter picks.

Butte County, ID: 1 Health Violation — 65/100 (2026)

2026 report: Butte County, ID scores 65/100 (Grade C). 3 ZIP codes analyzed. 6 EPA violations found. Free report with contaminant data and filter picks.

Camas County, ID: 1 Health Violation — 47/100 (2026)

2026 report: Camas County, ID scores 47/100 (Grade D). 3 ZIP codes analyzed. 4 EPA violations found. Free report with contaminant data and filter picks.

Canyon County, ID: 1 Health Violation — 72/100 (2026)

2026 report: Canyon County, ID scores 72/100 (Grade B). 16 ZIP codes analyzed. 67 EPA violations found. Free report with contaminant data and filter picks.

Caribou County, ID: 1 Health Violation — 64/100 (2026)

2026 report: Caribou County, ID scores 64/100 (Grade C). 6 ZIP codes analyzed. 9 EPA violations found. Free report with contaminant data and filter picks.

Cassia County, ID: 8 Health Violations — 71/100 (2026)

2026 report: Cassia County, ID scores 71/100 (Grade B). 6 ZIP codes analyzed. 53 EPA violations found. Free report with contaminant data and filter picks.

Clark County, ID: 1 Health Violation — 53/100 (2026)

2026 report: Clark County, ID scores 53/100 (Grade D). 2 ZIP codes analyzed. 2 EPA violations found. Free report with contaminant data and filter picks.

Clearwater County, ID: Lead Above EPA Limits — 57/100 (2026)

2026 report: Clearwater County, ID scores 57/100 (Grade C). 5 ZIP codes analyzed. 22 EPA violations found. Lead above EPA limits. Free report with conta...

Custer County, ID: 13 Violations — 49/100 (2026)

2026 report: Custer County, ID scores 49/100 (Grade D). 6 ZIP codes analyzed. 13 EPA violations found. Free report with contaminant data and filter picks.

Elmore County, ID: 13 Health Violations — 50/100 (2026)

2026 report: Elmore County, ID scores 50/100 (Grade D). 7 ZIP codes analyzed. 53 EPA violations found. Free report with contaminant data and filter picks.

Franklin County, ID: 6 Health Violations — 76/100 (2026)

2026 report: Franklin County, ID scores 76/100 (Grade B). 7 ZIP codes analyzed. 49 EPA violations found. Free report with contaminant data and filter pi...

Fremont County, ID: 1 Health Violation — 56/100 (2026)

2026 report: Fremont County, ID scores 56/100 (Grade C). 8 ZIP codes analyzed. 8 EPA violations found. Free report with contaminant data and filter picks.

Gem County, ID: 1 Health Violation — 80/100 (2026)

2026 report: Gem County, ID scores 80/100 (Grade B). 2 ZIP codes analyzed. 3 EPA violations found. Free report with contaminant data and filter picks.

Gooding County, ID: 9 Violations — 64/100 (2026)

2026 report: Gooding County, ID scores 64/100 (Grade C). 4 ZIP codes analyzed. 9 EPA violations found. Free report with contaminant data and filter picks.

Idaho County, ID: 11 Health Violations — 56/100 (2026)

2026 report: Idaho County, ID scores 56/100 (Grade C). 13 ZIP codes analyzed. 47 EPA violations found. Free report with contaminant data and filter picks.

Jefferson County, ID: 3 Health Violations — 69/100 (2026)

2026 report: Jefferson County, ID scores 69/100 (Grade C). 6 ZIP codes analyzed. 14 EPA violations found. Free report with contaminant data and filter p...

Jerome County, ID: 1 Health Violation — 81/100 (2026)

2026 report: Jerome County, ID scores 81/100 (Grade B). 3 ZIP codes analyzed. 34 EPA violations found. Free report with contaminant data and filter picks.

Kootenai County, ID: 6 Health Violations — 63/100 (2026)

2026 report: Kootenai County, ID scores 63/100 (Grade C). 15 ZIP codes analyzed. 27 EPA violations found. Free report with contaminant data and filter p...

Latah County, ID: Lead Above EPA Limits — 59/100 (2026)

2026 report: Latah County, ID scores 59/100 (Grade C). 12 ZIP codes analyzed. 57 EPA violations found. Lead above EPA limits. Free report with contamina...

Lemhi County, ID: 5 Health Violations — 46/100 (2026)

2026 report: Lemhi County, ID scores 46/100 (Grade D). 9 ZIP codes analyzed. 10 EPA violations found. Free report with contaminant data and filter picks.

Lewis County, ID: 1 Health Violation — 98/100 (2026)

2026 report: Lewis County, ID scores 98/100 (Grade A). 3 ZIP codes analyzed. 8 EPA violations found. Free report with contaminant data and filter picks.

Lincoln County, ID: 1 Health Violation — 81/100 (2026)

2026 report: Lincoln County, ID scores 81/100 (Grade B). 3 ZIP codes analyzed. 6 EPA violations found. Free report with contaminant data and filter picks.

Madison County, ID: 3 Health Violations — 82/100 (2026)

2026 report: Madison County, ID scores 82/100 (Grade B). 4 ZIP codes analyzed. 40 EPA violations found. Free report with contaminant data and filter picks.

Minidoka County, ID: 2 Health Violations — 73/100 (2026)

2026 report: Minidoka County, ID scores 73/100 (Grade B). 4 ZIP codes analyzed. 34 EPA violations found. Free report with contaminant data and filter pi...

Nez Perce County, ID: 7 Health Violations — 91/100 (2026)

2026 report: Nez Perce County, ID scores 91/100 (Grade A). 6 ZIP codes analyzed. 50 EPA violations found. Free report with contaminant data and filter p...

Owyhee County, ID: 5 Health Violations — 77/100 (2026)

2026 report: Owyhee County, ID scores 77/100 (Grade B). 5 ZIP codes analyzed. 43 EPA violations found. Free report with contaminant data and filter picks.

Payette County, ID: 9 Health Violations — 67/100 (2026)

2026 report: Payette County, ID scores 67/100 (Grade C). 3 ZIP codes analyzed. 21 EPA violations found. Free report with contaminant data and filter picks.

Power County, ID: 7 Health Violations — 61/100 (2026)

2026 report: Power County, ID scores 61/100 (Grade C). 4 ZIP codes analyzed. 21 EPA violations found. Free report with contaminant data and filter picks.

Shoshone County, ID: 11 Violations — 60/100 (2026)

2026 report: Shoshone County, ID scores 60/100 (Grade C). 13 ZIP codes analyzed. 11 EPA violations found. Free report with contaminant data and filter p...

Teton County, ID: 1 Health Violation — 74/100 (2026)

2026 report: Teton County, ID scores 74/100 (Grade B). 4 ZIP codes analyzed. 9 EPA violations found. Free report with contaminant data and filter picks.

Twin Falls County, ID: 12 Health Violations — 76/100 (2026)

2026 report: Twin Falls County, ID scores 76/100 (Grade B). 9 ZIP codes analyzed. 83 EPA violations found. Free report with contaminant data and filter ...

Valley County, ID: 6 Health Violations — 54/100 (2026)

2026 report: Valley County, ID scores 54/100 (Grade D). 5 ZIP codes analyzed. 38 EPA violations found. Free report with contaminant data and filter picks.

Washington County, ID: 8 Violations — 80/100 (2026)

2026 report: Washington County, ID scores 80/100 (Grade B). 3 ZIP codes analyzed. 8 EPA violations found. Free report with contaminant data and filter p...