Iowa earthquake risk
Scott County has the highest earthquake risk in Iowa, scoring 75.1 out of 100 — rated "Relatively Low" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Scott County | 75.1 | Relatively Low |
| 2 | Polk County | 66.8 | Relatively Low |
| 3 | Linn County | 57.2 | Very Low |
| 4 | Des Moines County | 56.7 | Very Low |
| 5 | Lee County | 55.5 | Very Low |
| 6 | Muscatine County | 54.1 | Very Low |
| 7 | Clinton County | 45.4 | Very Low |
| 8 | Johnson County | 45.1 | Very Low |
| 9 | Henry County | 43.6 | Very Low |
| 10 | Black Hawk County | 39.1 | Very Low |
| 11 | Jefferson County | 38.1 | Very Low |
| 12 | Wapello County | 37.3 | Very Low |
| 13 | Washington County | 35.6 | Very Low |
| 14 | Story County | 34.8 | Very Low |
| 15 | Davis County | 33.3 | Very Low |
| 16 | Appanoose County | 31.5 | Very Low |
| 17 | Van Buren County | 31.2 | Very Low |
| 18 | Dubuque County | 31.1 | Very Low |
| 19 | Marion County | 30.9 | Very Low |
| 20 | Woodbury County | 30.8 | Very Low |
| 21 | Louisa County | 30.2 | Very Low |
| 22 | Mahaska County | 29.5 | Very Low |
| 23 | Jasper County | 28.5 | Very Low |
| 24 | Marshall County | 27.5 | Very Low |
| 25 | Cedar County | 27.4 | Very Low |
| 26 | Pottawattamie County | 26.9 | Very Low |
| 27 | Jackson County | 26.4 | Very Low |
| 28 | Iowa County | 26.2 | Very Low |
| 29 | Dallas County | 25.6 | Very Low |
| 30 | Poweshiek County | 25.6 | Very Low |
| 31 | Delaware County | 24.6 | Very Low |
| 32 | Cerro Gordo County | 24.2 | Very Low |
| 33 | Union County | 24.2 | Very Low |
| 34 | Lucas County | 24.1 | Very Low |
| 35 | Keokuk County | 21.9 | Very Low |
| 36 | Tama County | 21.7 | Very Low |
| 37 | Jones County | 21.5 | Very Low |
| 38 | Page County | 20.7 | Very Low |
| 39 | Webster County | 20.6 | Very Low |
| 40 | Benton County | 20.5 | Very Low |
| 41 | Warren County | 20.5 | Very Low |
| 42 | Wayne County | 20.3 | Very Low |
| 43 | Carroll County | 19.8 | Very Low |
| 44 | Hardin County | 19.7 | Very Low |
| 45 | Buena Vista County | 19.4 | Very Low |
| 46 | Fayette County | 19.1 | Very Low |
| 47 | Sioux County | 19.1 | Very Low |
| 48 | Decatur County | 18.6 | Very Low |
| 49 | Taylor County | 18.5 | Very Low |
| 50 | Madison County | 17.9 | Very Low |
| 51 | Hamilton County | 17.1 | Very Low |
| 52 | Wright County | 16.8 | Very Low |
| 53 | Buchanan County | 16.7 | Very Low |
| 54 | Boone County | 16.6 | Very Low |
| 55 | Cass County | 16.2 | Very Low |
| 56 | Montgomery County | 16 | Very Low |
| 57 | Clarke County | 14.9 | Very Low |
| 58 | Calhoun County | 14.6 | Very Low |
| 59 | Clayton County | 14.5 | Very Low |
| 60 | Monroe County | 14.5 | Very Low |
| 61 | Plymouth County | 14.4 | Very Low |
| 62 | Bremer County | 14.3 | Very Low |
| 63 | Clay County | 14.2 | Very Low |
| 64 | Monona County | 14 | Very Low |
| 65 | Dickinson County | 13.4 | Very Low |
| 66 | Fremont County | 13.3 | Very Low |
| 67 | Adair County | 12.3 | Very Low |
| 68 | Allamakee County | 12 | Very Low |
| 69 | Chickasaw County | 12 | Very Low |
| 70 | Harrison County | 11.8 | Very Low |
| 71 | Pocahontas County | 11.8 | Very Low |
| 72 | Kossuth County | 11.5 | Very Low |
| 73 | Hancock County | 11.4 | Very Low |
| 74 | Greene County | 11.1 | Very Low |
| 75 | Floyd County | 11 | Very Low |
| 76 | Winnebago County | 10.8 | Very Low |
| 77 | Cherokee County | 10.7 | Very Low |
| 78 | Winneshiek County | 10.6 | Very Low |
| 79 | Grundy County | 10.1 | Very Low |
| 80 | Sac County | 10.1 | Very Low |
| 81 | Crawford County | 9.9 | Very Low |
| 82 | O'Brien County | 9.8 | Very Low |
| 83 | Guthrie County | 9.3 | Very Low |
| 84 | Osceola County | 9.3 | Very Low |
| 85 | Butler County | 9.2 | Very Low |
| 86 | Mills County | 8.9 | Very Low |
| 87 | Humboldt County | 8.6 | Very Low |
| 88 | Ringgold County | 8.6 | Very Low |
| 89 | Adams County | 8.2 | Very Low |
| 90 | Shelby County | 7.7 | Very Low |
| 91 | Franklin County | 7.5 | Very Low |
| 92 | Lyon County | 7.5 | Very Low |
| 93 | Howard County | 6.8 | Very Low |
| 94 | Audubon County | 6.7 | Very Low |
| 95 | Palo Alto County | 6.2 | Very Low |
| 96 | Ida County | 5.8 | Very Low |
| 97 | Emmet County | 5.2 | Very Low |
| 98 | Worth County | 4.8 | Very Low |
| 99 | Mitchell County | 4.7 | Very Low |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Earthquake risk nationally:
Other hazard risks in Iowa:
Frequently asked questions
What is the highest earthquake risk county in Iowa?
Scott County, IA has the highest earthquake risk in Iowa, with a FEMA National Risk Index score of 75.1 out of 100 (rated "Relatively Low").
What causes earthquake risk in Iowa?
Earthquake risk reflects expected annual losses from ground shaking. High scores concentrate in California, the Pacific Northwest, Alaska, and the New Madrid Seismic Zone (spanning Missouri, Arkansas, Tennessee, and neighboring states). NOAA's Storm Events Database does not track earthquakes, so recorded event counts are not shown.