Region
United States
17
Colorado
11
California
5
Florida
5
Chesapeake Bay Watershed
3
Florida Keys
3
Indiana
3
Mississippi River Watershed
3
North Carolina
3
Oregon
3
Pennsylvania
3
Arizona
2
Chesapeake Bay (Md. and Va.)
2
Connecticut
2
Great Lakes (North America)
2
Iowa
2
Long Island
2
Marion County
2
New Jersey
2
New York (State)
2
Poland
2
Rio Grande Valley (Colo.-Mexico and Tex.)
2
Shasta County
2
Southern States
2
Texas
2
Alaska
1
Black Mesa (Navajo County and Apache County)
1
Black Mesa (Navajo County and Apache County, Ariz.)
1
Burlington
1
Canada
1
Champlain, Lake
1
Chester County
1
Colorado River Watershed (Colo.-Mexico)
1
Columbia River Watershed
1
Conestoga River Watershed
1
Currituck Sound
1
Gauteng
1
Georgia
1
Gila River (N.M. and Ariz.)
1
Gila River Watershed (N.M. and Ariz.)
1
Gwinnett County
1
Hendricks County
1
Illinois
1
Iron Mountain Mine (Calif.)
1
Johnson Creek Watershed (Clackamas County and Multnomah County)
1
Kanawha River
1
Kanawha River (W. Va.)
1
Kissimmee River
1
Klamath Mountains (Calif. and Or.)
1
Louisiana
1
more ...