Clark Fork River
The Clark Fork, or the Clark Fork of the Columbia River, is a river in the U.S. states of Montana and Idaho, approximately 310 miles (500 km) long. The largest river by volume in Montana, it drains an extensive region of the Rocky Mountains in western Montana and northern Idaho in the watershed of the Columbia River. The river flows northwest through a long valley at the base of the Cabinet Mountains and empties into Lake Pend Oreille in the Idaho Panhandle. The Pend Oreille River in Idaho, Washington, and British Columbia, Canada which drains the lake to the Columbia in Washington, is sometimes included as part of the Clark Fork, giving it a total length of 479 miles (771 km), with a drainage area of 25,820 square miles (66,900 km2). In its upper 20 miles (32 km) in Montana near Butte, it is known as Silver Bow Creek. Interstate 90 follows much of the upper course of the river from Butte to Saint Regis. The highest point within the river's watershed is Mount Evans at 10,641 feet (3,243 m) in Deer Lodge County, Montana along the Continental Divide.
| Clark Fork Original name given by Lewis and Clark expedition: Clark's River | |
|---|---|
The Clark Fork at Missoula, Montana | |
Map of the Clark Fork, its main tributaries and downriver connection to the Columbia River via the Pend Oreille River. | |
| Location | |
| Country | United States |
| State | Montana, Idaho |
| Cities | Butte, Missoula |
| Physical characteristics | |
| Source | Silver Bow Creek |
| • location | Butte, Silver Bow County, Montana |
| • coordinates | 46°4′32″N 112°27′56″W |
| • elevation | 6,882 ft (2,098 m) |
| 2nd source | Warm Springs Creek (Montana) |
| • location | Flint Creek Range, Granite County, Montana |
| • coordinates | 46°15′39″N 113°8′12″W |
| • elevation | 7,466 ft (2,276 m) |
| Source confluence | |
| • location | Deer Lodge County, Montana |
| • coordinates | 46°11′12″N 112°46′18″W |
| • elevation | 4,795 ft (1,462 m) |
| Mouth | Lake Pend Oreille |
• location | Bonner County, Idaho |
• coordinates | 48°11′0″N 116°16′9″W |
• elevation | 2,064 ft (629 m) |
| Length | 310 mi (500 km) |
| Basin size | 22,905 sq mi (59,320 km2) |
| Discharge | |
| • location | Whitehorse Rapids near Cabinet, ID |
| • average | 21,930 cu ft/s (621 m3/s) |
| • minimum | 762 cu ft/s (21.6 m3/s) |
| • maximum | 195,000 cu ft/s (5,500 m3/s) |
| Basin features | |
| Tributaries | |
| • left | Bitterroot River |
| • right | Blackfoot River, Flathead River, Bull River |
The Clark Fork is a Class I river for recreational purposes in Montana from Warm Springs Creek to the Idaho border.