Region
United States
207
Massachusetts
5
Pennsylvania
5
Alaska
4
California
4
Chester County
4
Colorado
4
Kansas
3
South Sudan
3
Venezuela
3
Wyoming
3
Big Elk Creek Watershed (Pa. and Md.)
2
High Plains Aquifer
2
Iran
2
Iraq
2
Maryland
2
Nevada
2
New Hampshire
2
Washington (State)
2
Yemen (Republic)
2
Assabet River Watershed
1
Bedrock Region
1
Belarus
1
Big Sur
1
Big Thompson River
1
Brazil
1
Burma
1
Cape Cod Bay
1
Central African Republic
1
Charles River Watershed
1
Colombia
1
Colorado River (Colo.-Mexico)
1
Connecticut River
1
Cuba
1
Dauphin County
1
Delaware
1
Delaware River Watershed (N.Y.-Del. and N.J.)
1
Dolores River (Colo. and Utah)
1
Dolores River Region (Colo. and Utah)
1
Fallon Region
1
Florida
1
Germany
1
Green River Watershed
1
Gulf States
1
High Plains (U.S.)
1
Huntington Beach
1
India
1
Japan
1
Kentucky
1
Korea (North)
1
more ...