Lehigh River

About

Lehigh River, Pennsylvania — 1818 Lehigh Coal & Navigation, 1829 Lehigh Canal, 1965 Wild/Scenic, Jim Thorpe. The gauge at 01451000 tells the operational story: an average of roughly 1,850 CFS, with optimal paddling flows running 800 to 3,500 CFS through the gorge. The classic run drops 26 miles from White Haven to Jim Thorpe, Class II–IV through Lehigh Gorge, where Francis E. Walter Dam releases create reliable whitewater from April through October. Above White Haven the water eases to Class I–II, an upper approach; below Jim Thorpe the valley widens toward Allentown, again Class I–II. The full river runs 109 miles south and east, draining 1,355 square miles of Wayne, Lackawanna, Monroe, Carbon, and Lehigh Counties before meeting the Delaware at Easton.

The Lehigh Valley was Lenape homeland. Known in Lenape as Lechauwitank, "fork river," it sat at the center of Delaware territory in eastern Pennsylvania and supported large communities before European contact. Jim Thorpe — originally Mauch Chunk — was a major Lenape trading site long before it carried either name.

The industrial chapter began in 1818, when the Lehigh Coal & Navigation Company started operating the river as a private transportation corridor for anthracite. The Lehigh Navigation System, completed in 1829, turned the river into a coal highway carrying anthracite from the Schuylkill and Carbon County mines to Philadelphia. The canal system used 57 lift locks over 72 miles. It ran until the Lehigh Valley Railroad superseded it in the 1870s.

The river resisted the infrastructure laid across it. The catastrophic flood of 1862 swept away every dam, lock, canal boat, and village along the Upper Grand Division between White Haven and Jim Thorpe. Protection came slowly. The Lehigh earned a Wild and Scenic River designation in 1965, covering 72 miles. In 1979 the U.S. Army Corps of Engineers completed the Francis E. Walter Dam as a flood control structure upstream of Jim Thorpe, work that also created the 1,800-acre Beltzville Lake. The first comprehensive hydrological studies stretched across generations — USGS surveys in the 1870s–1890s, gauging stations established in the 1880s–1910s, state streamflow assessments through the 1930s, then water pollution control studies in the 1950s–1970s and Clean Water Act assessments from 1972 onward, all reckoning with a century of logging, agricultural, and industrial impacts.

Today the corridor centers on Lehigh Gorge State Park and the Francis E. Walter Dam recreation releases. Since 2023 the Lehigh Gorge Rail Trail — 26 miles on the former Central Railroad of New Jersey grade — has run parallel to the water, enabling paddle-and-bike combinations. Outfitters like Jim Thorpe River Adventures and Pocono Whitewater, rafting the gorge since 1980, work the same stretch the canal once served. The river that supported the Allentown, Bethlehem, and Jim Thorpe economies now carries paddlers past its own industrial scars.