South Fork Clearwater River

The South Fork Clearwater River is a 62-mile (100 km)[2] long river in north-central Idaho in the United States. Draining about 1,175 square miles (3,040 km2), the South Fork joins with the Middle Fork Clearwater River to form the Clearwater River, a major tributary of the Snake River.

South Fork Clearwater River
The river at the Chief Looking Glass Village site near Kooskia
South Fork Clearwater River is located in Idaho
South Fork Clearwater River
Location of the mouth of the South Fork Clearwater River in Idaho
South Fork Clearwater River is located in the United States
South Fork Clearwater River
South Fork Clearwater River (the United States)
Location
CountryUnited States
StateIdaho
Physical characteristics
SourceConfluence of American and Red Rivers
 • locationNear Elk City, Nez Perce National Forest
 • coordinates45°48′30″N 115°28′29″W / 45.80833°N 115.47472°W / 45.80833; -115.47472[1]
 • elevation3,901 ft (1,189 m)
MouthClearwater River
 • location
Kooskia, Idaho County
 • coordinates
46°08′45″N 115°58′57″W / 46.14583°N 115.98250°W / 46.14583; -115.98250[1]
 • elevation
1,224 ft (373 m)
Length62 mi (100 km)[2]
Basin size1,175 sq mi (3,040 km2)[3]
Discharge 
 • locationStites, about 4 mi (6.4 km) from the mouth[4]
 • average998 cu ft/s (28.3 m3/s)[4]
 • minimum44 cu ft/s (1.2 m3/s)
 • maximum13,800 cu ft/s (390 m3/s)
Basin features
Tributaries 
 • leftRed River (Idaho), Crooked River (Idaho County)
 • rightAmerican River (Idaho)

The South Fork has been entirely free flowing since the demolition of the Grangeville Dam in 1963.

Course edit

The river is formed by the confluence of the American River and Red River in the Nez Perce National Forest at an elevation of 3,901 ft (1,189 m). The roughly 20-mile (32 km) American River rises at 5,200 ft (1,600 m) and flows generally south to the confluence, while the northwest flowing Red River, rising at 6,100 ft (1,900 m), is about 25 mi (40 km) long. The American River is sometimes considered part of the main stem.[1] From the confluence the South Fork flows west through a canyon followed by Idaho State Highway 14, receiving the Crooked River from the left and Newsome Creek from the right before reaching Golden, where it receives Tenmile Creek from the left. Further west the river receives Johns Creek from the left, Meadow Creek from the right and Mill Creek from the left, and the gorge deepens to a maximum of some 2,000 ft (610 m) as the river swings north near Grangeville. From there the river flows generally north, past Harpster and Stites, before reaching its mouth on the Clearwater at Kooskia, at an elevation of 1,224 ft (373 m).[2]

Grangeville (Harpster) Dam was built on the South Fork in 1910 for hydroelectricity generation. In 1963, the dam was demolished,

Grangeville Dam edit

The Grangeville Dam, alternatively called the Harpster Dam, was located on the South Fork Clearwater River 5 miles (8.0 km) east of Grangeville. The 56-foot-tall (17 m), 440-foot-long (130 m) arched concrete hydroelectric dam was constructed by the Washington Water Power Company in 1910 and 1911. A wooden fish ladder had been installed but it collapsed in 1949. By the 1960s the dam's hydropower facilities had become obsolete. The decision was made to demolish the dam in the interest of fish passage, particularly that of Chinook salmon and steelhead trout.

The dam was destroyed by dynamite at 6:35 PM on August 19, 1963, following two prior detonations that day which had failed to collapse the structure.[5] At the time, the dam was the largest ever to be removed, a record which stood for decades.[6] Today, the entire South Fork and its headwater tributaries are free flowing and unobstructed by dams or major diversions.[7]

References edit

  1. ^ a b c "South Fork Clearwater River". Geographic Names Information System. United States Geological Survey, United States Department of the Interior. 1979-06-21. Retrieved 2013-06-13.
  2. ^ a b c USGS Topo Maps for United States (Map). Cartography by United States Geological Survey. ACME Mapper. Retrieved 2013-06-13.
  3. ^ "Clearwater River, South Fork Subbasin". Idaho Department of Environmental Quality. State of Idaho. Retrieved 2013-06-13.
  4. ^ a b "USGS Gage #13338500 on the South Fork Clearwater River at Stites, ID" (PDF). National Water Information System. U.S. Geological Survey. 1912–2012. Retrieved 2013-06-13.
  5. ^ Winter, Brian D. (April 1990). "A Brief Review of Dam Removal Efforts in Washington, Oregon, Idaho and California" (PDF). National Oceanic and Atmospheric Administration. Retrieved 8 September 2023.
  6. ^ McCully, Patrick (1996). "Getting Old: Dam Aging and Decommissioning". International Rivers. Zed Books. Retrieved 8 September 2023.
  7. ^ "Protecting Rivers: Dam Removal in Idaho". Idaho Rivers United. Archived from the original on April 3, 2012. Retrieved 2013-06-13.