Region
Texas
4
Gulf States
3
California
2
Columbia River Watershed
2
Great Basin
2
Great Plains
2
Hudson Bay Region
2
Illinois
2
Middle Atlantic States
2
Mississippi River
2
Mississippi River Valley
2
Missouri River
2
Missouri River Valley
2
New England
2
Ohio River
2
Ohio River Valley
2
Saint Lawrence River Valley
2
South Atlantic States
2
Washington (State)
2
Alaska
1
Colorado
1
Colorado River Watershed (Colo.-Mexico)
1
Columbia River Valley
1
DuPage County
1
Hawaii
1
Houston
1
Idaho
1
Indiana
1
Iowa
1
Mexico, Gulf of, Watershed
1
Mississippi River Watershed
1
New Mexico
1
Nueces River Watershed (Tex.)
1
Pennsylvania
1
Saint Lawrence River
1
Saint Lawrence River Watershed
1
Snake River Valley (Wyo.-Wash.)
1
Snake River Watershed (Wyo.-Wash.)
1