West Branch Susquehanna River

West Branch Susquehanna River
River
The eastern side of Williamsport, seen from the southeast on Bald Eagle Mountain. In the foreground is the West Branch of the Susquehanna River. Beyond Williamsport can be seen the higher part of the dissected Allegheny Plateau.
Country	United States
State	Pennsylvania
Regions	Cambria County, Indiana County, Clearfield County, Clinton County
Part of	Susquehanna River
Tributaries
- left	Sinnemahoning Creek, Pine Creek, Larrys Creek, Lycoming Creek, Loyalsock Creek, Muncy Creek
- right	Chest Creek, Anderson Creek, Clearfield Creek, Bald Eagle Creek, White Deer Hole Creek
Source	Allegheny Mountains
- location	Near Carrolltown, Cambria County
- coordinates	40°35′55″N 78°43′23″W / 40.59871°N 78.72311°W / 40.59871; -78.72311
Mouth	Susquehanna River
- location	Northumberland, Northumberland County
- elevation	423 ft (129 m)
- coordinates	40°52′55″N 76°47′51″W / 40.88194°N 76.79750°W / 40.88194; -76.79750Coordinates: 40°52′55″N 76°47′51″W / 40.88194°N 76.79750°W / 40.88194; -76.79750
Length	243 mi (391 km), West-east
Basin	6,847 sq mi (17,734 km2)
Discharge	for Lewisburg
- average	11,229 cu ft/s (318 m3/s)
- max	287,000 cu ft/s (8,127 m3/s)
Map of the West Branch Susquehanna River watershed

The West Branch Susquehanna River is one of the two principal branches, along with the North Branch, of the Susquehanna River in the northeastern United States. The North Branch, which rises in upstate New York, is generally regarded as the extension of the main branch, with the shorter West Branch being its principal tributary. The West Branch, which is 243 miles (391 km) long, is entirely within the state of Pennsylvania, draining a large mountainous area within the Allegheny Plateau in the western part of the state. Along most of its course it meanders along mountain ridges and through water gaps, forming a large zigzag arc through central Pennsylvania around the north end of the Allegheny Ridge. In colonial times the river provided an important water route to the Ohio River valley. In the 18th century, its lower valley became a significant industrial heartland of Pennsylvania. In the 20th century the upper reaches of the West Branch turned a yellow/orange color due to sulfurous drainage from nearby and abandoned deep bituminous coal mines.

The West Branch rises on the west side of the Alleghenies in northwestern Cambria County, just outside the borough of Carrolltown. It flows generally north, crossing the eastern corner of Indiana County at Cherry Tree, then into southern Clearfield County. Near Mahaffey it turns generally northeast and flows past Curwensville and Clearfield. In northern Clinton County it turns to the southeast to Lock Haven. At Lock Haven it turns east, flowing through the West Branch Susquehanna Valley along the foot of Bald Eagle Mountain ridge past Williamsport, the largest city on the river, then turns south at the end of the ridge. From there it winds around the Muncy, emerging from a water gap between Montour Ridge and Shamokin Mountain and joining the north (main) branch of the Susquehanna from the northwest approximately 2 miles (3 km) north of Sunbury.