GIS Map
RankingsIowaHighest hazard risk counties

Counties with the Highest Natural Hazard Risk in Iowa

The top 25 of 99 Iowa counties on GIS Map, ranked by FEMA National Risk Index score (0-100, national percentile).

#CountyRisk Index score
1Polk County
92.0
2Johnson County
87.4
3Linn County
86.7
4Scott County
84.9
5Woodbury County
83.3
6Pottawattamie County
80.4
7Black Hawk County
76.6
8Cerro Gordo County
69.6
9Story County
68.8
10Wapello County
65.3
11Clinton County
64.8
12Dubuque County
63.6
13Lee County
62.9
14Marshall County
62.5
15Crawford County
60.8
16Dallas County
60.6
17Cass County
60.1
18Webster County
60.0
19Hardin County
58.4
20Muscatine County
57.8
21Carroll County
57.6
22Des Moines County
55.8
23Sioux County
52.4
24Fayette County
50.9
25Davis County
50.3

Source: FEMA National Risk Index (December 2025). All counties with data are ranked. Estimates carry margins of error.

Citing this page: GIS Map, “Counties with the Highest Natural Hazard Risk in Iowa”, https://gismap.land/rankings/iowa/highest-risk-counties. Figures from FEMA National Risk Index (December 2025).

More Iowa rankings

Richest citiesMost expensive homesMost affordable homesHighest rentMost educatedHighest poverty rateMost densely populatedLargest by populationYoungestOldest by median ageFastest-growingFastest-shrinkingFastest-growing since 2010WarmestColdestSnowiestWettestDriestLowest hazard risk countiesHighest expected lossesHighest radon potentialWorst air qualityCleanest airWorst drought