Youghiogheny Sluice Gate Design

The US Army Corps of Engineers (USACE) owns and operates Youghiogheny Dam on the Youghiogheny River in southwestern Pennsylvania. The reservoir impounded by the embankment dam enables flood control, low-flow augmentation of the river, and a privately-operated 12-megawatt powerhouse. The project originated in 1943, and the USACE determined that the vertical lift gates that isolate the tunnel upstream of powerhouse were at the end of their service life. In 2022, the USACE enlisted Schnabel to design replacement lift gates that would comply with current USACE requirements and interface with the control tower’s existing fixed features.

Three 4-foot-wide, 20-foot-tall sluice gates operate on parallel branches of the outlet tunnel at the control section. These steel fixed-wheel gates operate under full head of 137 feet, and are positioned using an eyebar chain assembly in combination with a dogging device and wire rope hoist located in the control tower.

As part of an A/E IDIQ contract with the USACE Huntington District, the Aterra-Schnabel Joint Venture team designed replacement sluice gates and eyebar chains using contemporary materials and fabrication processes. Replacement gates and eyebar chains match the controlling dimensions of their existing counterparts. This interchangeability allows for flexibility in procurement and installation sequencing.

The project also involved the creation of BIM models of the gate and eyebar chain, and the preparation of technical and contract documents for their fabrication and delivery. The design project is complete and the replacement gates and eyebar chains are currently being fabricated.