Region
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South Dakota
6
West (U.S.)
6
Buffalo Creek (Logan County)
5
Columbia River Watershed
5
Glen Canyon National Recreation Area
5
Glen Canyon National Recreation Area (Utah and Ariz.)
5
Houston
5
Kentucky
5
Mississippi River Watershed
5
Saint Francis Dam (Calif.)
5
Santa Clara River
5
Utah
5
White River (Ind. : River)
5
White River (River)
5
Colorado River (Colo.-Mexico)
4
Grand Canyon
4
Guyana
4
Los Angeles
4
Maine
4
Mississippi
4
Montana
4
New Mexico
4
Ohio River
4
Red River of the North
4
Red River of the North Watershed
4
Rhode Island
4
South Carolina
4
Wisconsin
4
Wyoming
4
Appalachian Region
3
Atlantic Coast (U.S.)
3
Bangladesh
3
Baton Rouge
3
Buffalo Creek
3
California, Southern
3
Central Valley
3
Connecticut
3
Dallas
3
Ellicott City
3
Gila River (N.M. and Ariz.)
3
Grand Canyon National Park
3
Grand Forks
3
Hawaii
3
Honduras
3
Italy
3
Little Missouri River
3
Manitoba
3
Massachusetts
3
New Jersey
3
New Orleans
3
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