GIS Map
RankingsIowaWorst air quality

Counties with the Worst Air Quality in Iowa

The top 14 of 14 Iowa counties on GIS Map, ranked by median Air Quality Index, counting only counties that host an EPA air monitor.

#CountyMedian AQI
1Black Hawk County
47
2Clinton County
46
3Scott County
46
4Van Buren County
46
5Polk County
45
6Linn County
44
7Woodbury County
43
8Harrison County
42
9Montgomery County
42
10Palo Alto County
42
11Pottawattamie County
42
12Bremer County
40
13Johnson County
39
14Muscatine County
38

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 Worst Air Quality in Iowa”, https://gismap.land/rankings/iowa/worst-air-quality-counties. Figures from EPA Air Quality Index annual summary (2024).

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