PITTSBURGH – Scooping up rocks and soil from the river may seem simple. After all, who hasn’t played with dirt, shovels or excavating toys on the beach when they were kids?
Except, dredging the bottom of the Monongahela River isn’t anything like playing on the beach, and it’s no child’s play. It is hard work requiring laser-focused coordination, planning, soil testing and precision.
“Our contractor has been doing a great job,” said Sgt. 1st Class Jonathan Baker, the quality assurance representative validating the work daily for the U.S. Army Corps of Engineers Pittsburgh District.
The Pittsburgh District contracted a crew to dredge the Monongahela River between the towns of Elizabeth and Charleroi. The work began in mid-September 2024. Dredging clears the way for industries to transport bulk commodities through the southern region of Pittsburgh.
“Without it, navigation on the river would be severely hampered. The industry understands the need for this work, and so do we,” said Art Innamorato, the contractor’s construction manager. “This work is challenging but rewarding. No two days are ever the same.”
Dredging became necessary when the pool level dropped approximately two feet in the summer of 2024 after the Pittsburgh District removed the navigation dam near Elizabeth due to its aging infrastructure and costly lock maintenance repairs. The removal of the navigation facility created 33 miles of unobstructed riverway.
However, lowering the pool exposed shallow areas upstream of Elizabeth. The district is responsible for maintaining at least a nine-foot draft for larger vessels transporting goods such as coal or construction material.
The contractor has been operating two dredging crews six days a week since the channel restoration began. So far, crews have removed more than 314 barges of sediment, totaling 166,000 tons of soil, rock, and debris from the river bottom.
The Pittsburgh District plans to lower the channel another foot to a final elevation of 723.1 feet, but only after careful assessment of the impact on shoreside industries, navigation, and other stakeholders.
Dredging is complex and meticulously planned operation. Each rig is outfitted with a port-sized excavator, a barge capable of holding over 500 tons of material, and a towboat to maneuver their setup into position. Crews use state-of-the-art radar and sonar mapping systems to create 3D contour maps of the riverbed, which ensure precise execution of dredging where needed. These maps, generated using millions of data points, allow operators to track depth changes and real time validation of their work.
As a safety measure, the towboat captains rely on a “Rose Point” navigation system to monitor nearby vessels. When commercial towboats pass through the dredging zone, crews pull their spuds – vertical anchors that stabilize their rigs – and momentarily pause operations to allow safe passage. Once the vessel clears, dredging resumes without significant delays.
Despite their high-tech capabilities, crews have faced heavy challenges – literally. On a few occasions, the excavator clam grabbed hold of boulders too heavy to lift. One boulder was the size of a dining room table. It was too heavy to remove from the water. Instead, the crew dragged the boulder out of the channel’s navigation path toward the riverbank to keep vessels safe.
“Some boulders are just too big to remove, so we have to work around them,” Innamorato said.
In 2000, the Pittsburgh District performed a dredging contract in the Monongahela River specifically to remove sediment and material that did not meet environmental standards. That material was taken to a commercial facility authorized to receive those types of wastes.
The current dredging consists of mostly sands and gravel, transported daily to a site known as “Victory Hollow” owned and operated locally by the U.S. Army Corps of Engineers. All the material disposed here has been tested and determined to meet Pennsylvania’s Management of Fill Policy.
“When conducting Lower Mon dredging, we do annual checks for any changes in the environment or spills in the areas that may affect the locations where we will be,” said Bobbi Jo McClain, the Pittsburgh District’s chief of the environmental section.
Additionally, the contractor inspects the machinery regularly to minimize any leaks from the excavator’s hydraulic lines. The contractor checks the bucket at the beginning and end of each 12-hour shift, as well as once during the shift to mitigate any negative impact to aquatic life.
“We monitor it closely,” Innamorato said.
The contractor performing the work is a company with extensive experience in river dredging and salvage work. The same contractor previously contributed to pier repairs at Montgomery Locks and Dams and performed emergency operations at Dashields Locks and Dams. They are experts in handling floating heavy equipment vital to the project’s success. Their work extends beyond dredging; they also specialize in raising sunken barges, installing massive lock gates, and providing salvage services when extreme weather causes breakaways.
But the contractor does not do it alone. The Pittsburgh District oversees and has planned the dredging efforts since day one.
“Our job is to validate the contractor’s work,” said Baker, whose role involves meticulously time-stamping operations from morning to evening, ensuring compliance with contract specifications. “The contractor has been doing a fantastic job. Outside of Mother Nature’s interruptions, they’ve been nonstop.”
Beyond excavation, coordination plays a crucial role in the operation. Dredging any river near a populated city requires extreme caution. Before digging begins, crews must identify underwater utilities such as power lines, gas mains and communication cables. In one instance, the contractors discovered a fiber-optic line and a high-pressure gas main within the dredging zone. They formulated a plan to complete the work without causing costly damage to critical infrastructure.
Data management is another crucial component. The Army Corps supplies contractors with detailed files containing extensive latitude, longitude, and depth data to provide their dredging guidance. The contractor’s operators rely on this data to maintain accurate depths while ensuring minimal environmental and industrial impact.
For the crew members, the work is more than just a job – it’s a complex puzzle requiring skill, adaptability, and teamwork. One worker described the daily satisfaction of tackling unique challenges, from maneuvering large rigs around tight river bends to safely relocating oversized debris.
“You never know what you’re going to pull up from the river,” Innamorato said. “We’ve found everything from massive boulders and trees to old sheet piling left over from decades ago.”
Contractors expect dredging to continue into late spring and possibly summertime. Afterward, the Pittsburgh District will reassess the river’s conditions before deciding on the next steps. Until then, the crews remain focused on their mission: ensuring the Monongahela River remains a navigable and vital artery for commerce, industry, and the communities that rely on it.