United States 125 California 17 Wyoming 12 New York (State) 5 New Jersey 4 Texas 4 Canada 3 Delmarva Peninsula 3 Maryland 3 New Zealand 3 San Joaquin River Watershed 3 Washington (State) 3 Delta Region 2 Developing countries 2 Florida 2 Great Britain 2 Illinois 2 India 2 Long Island 2 Middle West 2 Nebraska 2 North America 2 North Dakota 2 Pennsylvania 2 Platte River 2 Sacramento River Watershed 2 Santa Ana River Watershed 2 Tennessee 2 Tropics 2 Alabama 1 Alamo River 1 Albany County 1 Anacostia River Watershed (Md. and Washington, D.C.) 1 Appalachian Region 1 Beaver Creek Watershed 1 Beaver Creek Watershed (Caroll County, Tenn.) 1 Berkeley County 1 Campbell County 1 Carbon County 1 Carroll County 1 Central America 1 Central Valley (Valley) 1 Clackamas River Watershed 1 Clarke County 1 Colorado 1 Columbia Plateau 1 Columbia River Watershed 1 Converse County 1 Costa Rica 1 Croton River Watershed 1 more ...