Region
Colorado
23
United States
10
West (U.S.)
7
California
3
New Mexico
3
Oregon
3
Colorado River (Colo.-Mexico)
2
Columbia River Region
2
Pojoaque River
2
Pojoaque River Valley (N.M.)
2
Snake River Region (Wyo.-Wash.)
2
Arizona
1
Arkansas River
1
Asia
1
Canada
1
Carson River
1
Cherry Creek Watershed
1
Colorado River Watershed (Colo.-Mexico)
1
Idaho
1
Klamath Basin
1
Middle East
1
Nevada
1
Republican River (Neb. and Kan.)
1
South Platte River (Colo. and Neb.)
1
South Platte River Watershed (Colo. and Neb.)
1
Southwest, New
1
Truckee River (Calif. and Nev.)
1
Truckee River Watershed (Calif. and Nev.)
1
Upper Klamath Lake Watershed (Or.)
1