Region
United States
164
California
28
Texas
28
Arizona
26
Washington (State)
25
Indiana
19
Mississippi River
19
Missouri
19
New York (State)
18
Pennsylvania
18
England
17
North Dakota
16
Louisiana
14
Mississippi River Valley
14
Florida
13
Georgia
13
Illinois
13
Middle West
12
Ohio
12
Alaska
11
Arkansas
11
Colorado
11
Northeastern States
11
Tennessee
11
West Virginia
11
Kansas
10
Iowa
9
Minnesota
9
Missouri River Watershed
9
Oklahoma
9
Oregon
8
Southern States
8
China
7
Missouri River
7
Netherlands
7
Nevada
7
Puerto Rico
7
Alabama
6
Arkansas River
6
Glen Canyon Dam
6
Glen Canyon Dam (Ariz.)
6
Idaho
6
Johnstown (Cambria County)
6
Maryland
6
Mexico
6
Nebraska
6
New England
6
North America
6
North Carolina
6
Pakistan
6
more ...