Alamosa River

Alamosa River
The river at Capulin.
Etymology"of cottonwood"
Location
CountryUnited States
StateColorado
Physical characteristics
Source 
  coordinates37°21′44″N 106°37′12″W / 37.36222°N 106.62000°W / 37.36222; -106.62000
MouthRio Grande
  location
arid land south of Alamosa
  coordinates
37°23′54″N 106°50′20″W / 37.39833°N 106.83889°W / 37.39833; -106.83889
Length64 mi (103 km), west-east
Basin size148 sq mi (380 km2)

The Alamosa River is a river in the southern part of the U.S. state of Colorado. It is about 64 miles (103 km) long, flowing roughly east through the San Luis Valley. Its watershed comprises about 148 square miles (380 km2).

The river's name means "shaded with cottonwoods" in Spanish.

The river was affected by the Summitville mine disaster, the worst cyanide spill in United States history.