South Fork Salmon River

South Fork Salmon River
Rafters on the South Fork Salmon River
Map showing the Salmon River basin. The South Fork is the second major tributary from left.
Location
CountryUnited States
StateIdaho
Physical characteristics
Sourcenear Monumental Peak
  locationSalmon River Mountains, Valley County
  coordinates44°28′47″N 115°41′06″W / 44.47972°N 115.68500°W / 44.47972; -115.68500
  elevation7,600 ft (2,300 m)
MouthSalmon River
  location
near Mackay Bar, Idaho County
  coordinates
45°22′40″N 115°30′47″W / 45.37778°N 115.51306°W / 45.37778; -115.51306
  elevation
2,146 ft (654 m)
Length86 mi (138 km)
Basin size1,309 sq mi (3,390 km2)
Discharge 
  locationMackay Bar
  average1,983 cu ft/s (56.2 m3/s)
  minimum318 cu ft/s (9.0 m3/s)
  maximum21,600 cu ft/s (610 m3/s)
Basin features
Tributaries 
  leftSecesh River
  rightEast Fork, Elk Creek

The South Fork Salmon River is an 86-mile (138 km) tributary of the Salmon River in Idaho and Valley Counties in central Idaho. The river drains a rugged, lightly populated wilderness watershed in the Salmon River Mountains. It is the second-largest tributary of the Salmon River, after the Middle Fork.