Region
Abū Ẓaby (Emirate)
1
Alaska
2
Albert Pike Recreation Area
1
Albuquerque
3
Alviso Region
1
Amargosa Desert (Nev. and Calif.)
1
Arctic Ocean
1
Arikaree Aquifer
2
Arizona
3
Arkansas
3
Arkansas River Watershed
1
Arnold Air Force Base
1
Arnold Air Force Base (Tenn.)
1
Assateague Island (Md. and Va.)
1
Atlantic Coast (South Atlantic States)
1
Barnstable
1
Barstow
1
Baton Rouge
2
Beaufort Sea
1
Big Cypress National Preserve
1
Big Sioux Aquifer
1
Big Sioux Aquifer (S.D.)
2
Birch Creek (Lemhi County-Butte County)
1
Biscayne Aquifer (Fla.)
1
Bremerton
1
Breton Sound
1
Breton Sound (La.)
1
Broward County
1
Bushy Park Reservoir (S.C.)
1
California
14
Cape Cod
1
Cape Lookout National Seashore
1
Cape Lookout National Seashore (N.C.)
1
Cape May County
1
Carraízo Reservoir Watershed
1
Carraízo Reservoir Watershed (P.R.)
1
Carson River Watershed
2
Cascadia Subduction Zone
1
Cattaraugus Indian Reservation
1
Cedar Rapids
1
Cedar River Watershed (Minn. and Iowa)
1
Central Oklahoma Aquifer
1
Charleston Region
1
Chattahoochee River National Recreation Area
1
Chattahoochee River National Recreation Area (Ga.)
1
Chesapeake Bay Watershed
1
China
1
Chukchi Sea
1
Citizen Potawatomi Nation, Oklahoma
1
Clark County
1
more ...