6 is the remnant of a historic lock and dam complex located along the Ohio River at Industry, Pennsylvania, United States.

Construction began at the site on June 2, 1892, several years before many of Pennsylvania's other Ohio River dams were started.

[3] The complex was named for William Emery Merrill,[3] an officer of the United States Army Corps of Engineers who had been responsible for the earliest successful Ohio River dam in Pennsylvania.

In the early 1920s, the engines in the powerhouse were converted from coal-burning to oil-burning; this was a purely interior change and had no effect on the exterior of the building.

[2] The lock master's residence, located downstream of the powerhouse,[7] was removed at some point after the property was listed on the Register.