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RankingsIdahoCleanest air

Counties with the Cleanest Air in Idaho

The top 20 of 20 Idaho counties on GIS Map, ranked by lowest median Air Quality Index, counting only counties that host an EPA air monitor.

#CountyMedian AQI
1Custer County
6
2Boundary County
17
3Blaine County
19
4Bonneville County
22
5Franklin County
22
6Twin Falls County
23
7Kootenai County
24
8Latah County
27
9Nez Perce County
29
10Bonner County
32
11Canyon County
36
12Lemhi County
37
13Valley County
37
14Bannock County
39
15Butte County
42
16Idaho County
42
17Benewah County
43
18Ada County
44
19Shoshone County
46
20Boise County
48

Source: EPA Air Quality Index annual summary (2024). All counties with data are ranked. Estimates carry margins of error.

Citing this page: GIS Map, “Counties with the Cleanest Air in Idaho”, https://gismap.land/rankings/idaho/cleanest-air-counties. Figures from EPA Air Quality Index annual summary (2024).

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