The Beaverhead River is an approximately tributary of the Jefferson River in southwest

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columbi ...

(east of the

Continental Divide A continental divide is a drainage divide on a continent such that the drainage basin on one side of the divide feeds into one ocean or sea, and the basin on the other side either feeds into a different ocean or sea, or else is endorheic, not ...

). It drains an area of roughly . The river's original headwaters, formed by the confluence of the Red Rock River and Horse Prairie Creek, are now flooded under

Clark Canyon Reservoir Clark Canyon Dam is an earthfill dam located in Beaverhead County, Montana, about 20 miles (30 km) south of the county seat of Dillon. The dam impounds the waters of the Beaverhead River, creating a body of water known as Clark Canyon Reserv ...

, which also floods the first of the river. The Beaverhead then flows through a broad valley northward to join the Big Hole River and form the Jefferson River. With the Red Rock River included in its length, the river stretches another , for a total length of , one of the more significant drainages of south-western Montana. The name of the Beaverhead originates from

Beaverhead Rock Beaverhead Rock, also known as Point of Rocks, is a rock formation overlooking the Beaverhead River in Montana protected as Beaverhead Rock State Park. It is located on Montana State Highway 41, south of Twin Bridges, Madison County. It was ad ...

on the middle river. This rock formation was recognized by Sacajawea when the

Lewis and Clark Expedition The Lewis and Clark Expedition, also known as the Corps of Discovery Expedition, was the United States expedition to cross the newly acquired western portion of the country after the Louisiana Purchase. The Corps of Discovery was a select gro ...

passed the area in 1805. There were also many

beaver Beavers are large, semiaquatic rodents in the genus ''Castor'' native to the temperate Northern Hemisphere. There are two extant species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers ar ...

s in the area at the time, but the name does not originate from the animal. In 1805, Captain

Meriwether Lewis Meriwether Lewis (August 18, 1774 – October 11, 1809) was an American explorer, soldier, politician, and public administrator, best known for his role as the leader of the Lewis and Clark Expedition, also known as the Corps of Discovery, with ...

traveled up the Jefferson and Beaverhead first, but when the rest of the expedition came, a sign Lewis had left at the confluence of the Beaverhead and Big Hole telling them to follow the Beaverhead had been cut down by a beaver, and the expedition traveled up the Big Hole instead. As a result, the swifter current of the Big Hole swamped two of their canoes before they could travel back down to the confluence. Together with the Red Rock River, the Beaverhead forms the uppermost headwaters of the Missouri River, the longest tributary of the

Mississippi River The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it f ...

. The river is a Class I water from the Clark Canyon Dam to its confluence with the Jefferson River for the purposes of public access for recreational purposes.Stream Access in Montana

References

{{authority control Rivers of Montana Rivers of Beaverhead County, Montana Bodies of water of Madison County, Montana

See also

References