Inland Counties With the Greatest Flood Risk

By Evan Comen • November 4, 2025

https://climate-crisis-247-bucket.nyc3.digitaloceanspaces.com/wp-content/uploads/2025/11/04000639/County-Level-Riverine-Flooding-Risk-150x150.png

This week, a strong Pacific storm system is delivering heavy precipitation to cities on the West Coast. More than two dozen cities are forecast to receive more than three inches of rain in a 72-hour period, with some small towns forecast to receive nearly five inches. The National Weather Service has issued flood watches in a number of populous counties, covering millions of Americans.

While the coastal United States is increasingly flood-prone, flood risk extends far inland. America’s rivers regularly overflow their banks, causing billions of dollars in property damage every year. Flood risk is worst along the Mississippi River corridor, while several flood-prone pockets in the banks of the Missouri and Ohio Rivers also see regular, damaging flood activity. A closer look at the data reveals the inland counties with the greatest flood risk.

To determine the inland counties with the greatest flood risk, Climate Crisis 247 reviewed data on riverine flooding from FEMA’s National Risk Index. Counties were ranked based on composite riverine flood risk score, a function of annualized, historic flood losses from 1996 to 2014. Supplemental data on total population is from the U.S. Census Bureau.

25. Riverside County, CA

Photo by john ko on Unsplash

Score of annual losses from riverine flooding: 98.5/100
Number of riverine flood events, 1996-2019: 161 events
Largest river: Colorado River
Total population: 2,449,909
County seat: Riverside

24. Boulder County, CO

Photo by StockSnap on Pixabay

Score of annual losses from riverine flooding: 98.6/100
Number of riverine flood events, 1996-2019: 18 events
Largest river: Saint Vrain Creek
Total population: 328,317
County seat: Boulder

23. Dauphin County, PA

Photo by Andre Frueh on Unsplash

Score of annual losses from riverine flooding: 98.6/100
Number of riverine flood events, 1996-2019: 53 events
Largest river: Susquehanna River
Total population: 287,484
County seat: Harrisburg

22. Travis County, TX

Photo by Carlos Delgado on Unsplash

Score of annual losses from riverine flooding: 98.7/100
Number of riverine flood events, 1996-2019: 141 events
Largest river: Colorado River
Total population: 1,307,625
County seat: Austin

21. Larimer County, CO

Photo by Jasper Gribble on Unsplash

Score of annual losses from riverine flooding: 98.9/100
Number of riverine flood events, 1996-2019: 37 events
Largest river: Laramie River
Total population: 363,561
County seat: Fort Collins

20. Guadalupe County, TX

Photo by Justin Wolff on Unsplash

Score of annual losses from riverine flooding: 99.0/100
Number of riverine flood events, 1996-2019: 80 events
Largest river: Guadalupe River
Total population: 178,368
County seat: Seguin

19. Comal County, TX

Photo by Justin Wolff on Unsplash

Score of annual losses from riverine flooding: 99.0/100
Number of riverine flood events, 1996-2019: 103 events
Largest river: Guadalupe River
Total population: 174,552
County seat: New Braunfels

18. Cook County, IL

Photo by Ozzie Stern on Unsplash

Score of annual losses from riverine flooding: 99.0/100
Number of riverine flood events, 1996-2019: 141 events
Largest river: Fox River
Total population: 5,185,812
County seat: Chicago

17. Washington County, UT

Photo by James Hon on Unsplash

Score of annual losses from riverine flooding: 99.1/100
Number of riverine flood events, 1996-2019: 145 events
Largest river: Virgin River
Total population: 189,827
County seat: St. George

16. Bexar County, TX

Photo by Chandra Maharzan on Unsplash

Score of annual losses from riverine flooding: 99.2/100
Number of riverine flood events, 1996-2019: 190 events
Largest river: San Antonio River
Total population: 2,037,344
County seat: San Antonio

15. Hays County, TX

Photo by Efren Chavez on Unsplash

Score of annual losses from riverine flooding: 99.2/100
Number of riverine flood events, 1996-2019: 96 events
Largest river: Pedernales River
Total population: 256,429
County seat: San Marcos

14. San Bernardino County, CA

Photo by Daryan Shamkhali on Unsplash

Score of annual losses from riverine flooding: 99.2/100
Number of riverine flood events, 1996-2019: 302 events
Largest river: Colorado River
Total population: 2,187,816
County seat: San Bernardino

13. Linn County, IA

Photo by Joel Drzycimski on Unsplash

Score of annual losses from riverine flooding: 99.3/100
Number of riverine flood events, 1996-2019: 60 events
Largest river: Iowa River
Total population: 229,463
County seat: Cedar Rapids

12. Montgomery County, TX

Photo by Obed Esquivel-Pickett on Unsplash

Score of annual losses from riverine flooding: 99.3/100
Number of riverine flood events, 1996-2019: 44 events
Largest river: West Fork San Jacinto River
Total population: 654,722
County seat: Conroe

11. Somerset County, NJ

Photo by Lexi Zotomayor on Unsplash

Score of annual losses from riverine flooding: 99.4/100
Number of riverine flood events, 1996-2019: 165 events
Largest river: Passaic River
Total population: 346,203
County seat: Somerville

10. Wayne County, MI

Photo by Doug Zuba on Unsplash

Score of annual losses from riverine flooding: 99.5/100
Number of riverine flood events, 1996-2019: 61 events
Largest river: Huron River
Total population: 1,773,767
County seat: Detroit

9. Ascension Parish, LA

Photo by Joshua J. Cotten on Unsplash

Score of annual losses from riverine flooding: 99.5/100
Number of riverine flood events, 1996-2019: 16 events
Largest river: Mississippi River
Total population: 128,593
County seat: Donaldsonville

8. Kern County, CA

Photo by Fabio Sasso on Unsplash

Score of annual losses from riverine flooding: 99.5/100
Number of riverine flood events, 1996-2019: 132 events
Largest river: Kern River
Total population: 910,433
County seat: Bakersfield

7. Jefferson County, AL

Photo by Lance Asper on Unsplash

Score of annual losses from riverine flooding: 99.6/100
Number of riverine flood events, 1996-2019: 95 events
Largest river: Black Warrior River
Total population: 669,744
County seat: Birmingham

6. Washoe County, NV

Photo by Daniel Akre on Unsplash

Score of annual losses from riverine flooding: 99.7/100
Number of riverine flood events, 1996-2019: 33 events
Largest river: Truckee River
Total population: 491,770
County seat: Reno

5. Davidson County, TN

Photo by Mike Gattorna on Unsplash

Score of annual losses from riverine flooding: 99.7/100
Number of riverine flood events, 1996-2019: 94 events
Largest river: Cumberland River
Total population: 709,846
County seat: Nashville

4. Livingston Parish, LA

Photo by Jp Valery on Unsplash

Score of annual losses from riverine flooding: 99.7/100
Number of riverine flood events, 1996-2019: 13 events
Largest river: Amite River
Total population: 145,583
County seat: Livingston

3. Lafayette Parish, LA

Photo by Nicole Herrero on Unsplash

Score of annual losses from riverine flooding: 99.8/100
Number of riverine flood events, 1996-2019: 44 events
Largest river: Bayou Teche
Total population: 245,075
County seat: Lafayette

2. Shelby County, TN

Photo by Joshua J. Cotten on Unsplash

Score of annual losses from riverine flooding: 99.9/100
Number of riverine flood events, 1996-2019: 129 events
Largest river: Mississippi River
Total population: 922,195
County seat: Memphis

1. East Baton Rouge Parish, LA

Photo by Vladimir Oprisko on Unsplash

Score of annual losses from riverine flooding: 99.9/100
Number of riverine flood events, 1996-2019: 31 events
Largest river: Mississippi River
Total population: 452,821
County seat: Baton Rouge

Finding a fiduciary financial advisor doesn't have to be hard. SmartAsset's free tool matches you with up to 3 financial advisors that serve your area in 5 minutes.
Each advisor has been vetted by SmartAsset and is held to a fiduciary standard to act in your best interests. Get on the path toward achieving your financial goals!