Monongahela River Locks and Dam no. 3 Demolition

Elizabeth, PA
DemolitionMarine ConstructionStructures
  1. Home
  2. Monongahela River Locks and Dam no. 3 Demolition
Location: Elizabeth, PA
Owner: US Army Corps of Engineers, Pittsburgh District
Construction Company: Fay, S&B USA Construction
Project Status: Construction began April 2024
This project consists of work associated with Monongahela River Locks and Dam no. 3 demolition, establishment of the new navigable channel and stabilization of the monoliths to remain after construction. Fay will breach the existing dam for pool equalization; demolish several structures, including dam no. 3, the middle wall, the river wall, the upper guard wall cells, and the river chamber extension cells; then place stability berms within the land chamber adjacent to the land wall and left dam abutment. Afterwards, Fay will install permanent stabilization measures for the flume way, land wall, upper guide walls and dam abutment.
Mon Locks & Dam project image 1
The existing concrete dam will be removed through a series of 14 blast events.
Mon Locks & Dam project image 2
One of the biggest challenges Fay faces on this project will be the unfavorable river conditions, as can be seen in this picture.
Mon Locks & Dam project image 3
Fay will provide environmental protection by allowing enough time for mussels along the banks of pool 3 to migrate to the new water elevation prior to construction.
Mon Locks & Dam project image 4
It is our goal to process and reuse as much demolition material as possible.

Impacting Local Communities


Upon completion, this project will have a positive impact on local businesses that rely on the river to conduct business. With the lock and dam eliminated, boats and barges will be able to move unrestricted through a longer stretch of river, enabling them to make deliveries faster. The larger pool will provide greater stability of river elevations, which is also a positive impact to local businesses.
 

New Navigable Channel


This project will include the construction and opening of the new navigable channel. Once the Monongahela River Locks and Dam no. 3 has been demolished, Fay will survey 300 ft upstream and 600 ft downstream of the removed dam to locate material above the required demolition elevation. If any high spots are located, Fay will dredge the new channel to remove them. Once the new navigable channel is open, the land and river chambers will be permanently closed for the demolition of the river and middle wall. We will finish this project with the placement of stability berms on the river face of the land wall, filling the flume way and placing a new concrete cap on the esplanade.  
 

Scope of Work


This project will demolish several structures at Monongahela River Locks and Dam no. 3, including the dam, the middle wall, the river wall, the upper guard wall cells, and the river chamber extension cells. Fay will also establish the new navigable channel and refurbish the land wall.
 

Project Timeline


Fay started work in late April. This summer, our first blast is scheduled for July 8, 2024, and complete dam removal and opening of the new navigation channel is expected to happen by December 4, 2024. Afterwards, Fay will continue to remove the middle and river walls, fill the flume way, place the stability berm along land wall and new concrete cap on the esplanade. All contract work is scheduled to be complete by November 20, 2026.