Lowering the Monongahela River Pool – Effects at Nearby River Facilities

Vessel operations along the inland waterways are hindered by low water conditions that can be created by large scale civil works projects. Demolition of Locks and Dam 3 in Elizabeth, PA began in July 2024 as the final phase of the Lower Monongahela River Project. The project is intended to provide 30 miles (48 km) of unimpeded navigation along the Monongahela River, providing more efficient transport of bulk commodities. Demolition resulted in an average river pool drop of at least 3.2 ft (1.0 m). This paper highlights the design considerations and challenges to account for upstream or downstream effects from large civil works projects, including dredging and disposal, stability of existing structures, and mooring and breasting modifications.