Emsworth Locks and Dam

By United States Army Corps of Engineers - U.S. Army Corps of Engineers Digital Visual Library, Public Domain

Location:

Emsworth Locks and Dams, Pittsburgh, PA 15225

Description:

Emsworth Locks and Dam is a major river navigation facility on the Ohio River in Emsworth, Allegheny County, Pennsylvania, just downstream from Pittsburgh. It was constructed beginning in 1919–1922 to replace older wicket‑type dams and locks, forming an essential part of the slackwater navigation system that allows large commercial and recreational vessels to traverse the Ohio River reliably. The complex consists of two gated dams—one on the main channel and another on the back channel near Neville Island—as well as two locks: a large lock for commercial barge traffic (600 ft by 110 ft) and a smaller auxiliary lock (360 ft by 56 ft) for recreational craft and smaller vessels.

Architecturally and engineering‑wise, Emsworth is notable as one of the oldest gated dam systems on the Ohio River, featuring vertical‑lift gates supported by tall concrete piers and machinery that raise and lower the gates to control water levels. Between 1935 and 1938, the original fixed‑crest structure was modified to a movable‑crest dam to increase the upstream pool depth to accommodate larger modern barges. Additional major rehabilitation work took place in the early 1980s to modernize electrical and lock machinery and to resurface critical structural elements, ensuring the facility’s continued role in regional navigation.

The locks and dam remain a vital piece of inland waterway infrastructure, supporting hundreds of commercial and recreational lockages monthly and helping to maintain navigable depths for river traffic upstream toward Pittsburgh.