Charleroi Riverside Chamber Nears Completion On Lower Mon

Operational testing is taking place on the new, expanded riverside lock chamber at Lock 4 on the Monongahela River in Charleroi, Pa., with the chamber expected to be complete this summer.

Testing Underway

Currently, a functional integration system test is taking place at the facility at Monongahela Mile 41.5, making sure all the lock’s mechanisms work well together to fill and drain the chamber. By mid-March, a second, 60-day troubleshooting test period is expected to begin that will include industry running tows through the new chamber, said Stephen Frost, who is managing the project for the Pittsburgh Engineer District.

“We would expect industry would be able to use it as a normal lock through without restrictions” during that testing period, Frost said.

The riverside lock chamber is now 720 feet long and 84 feet wide. Previously it was 360 feet long and 84 feet wide, meaning it took three hours and multiple cuts for a tow to lock through. A typical commercial tow should be able to lock through the expanded chamber in about 40 minutes, Frost said.

Trumbull Corporation and Brayman were awarded the River Chamber Completion Contract at Charleroi in 2015 as a joint business venture. The chamber was emptied in 2021 to complete the work.

Renaming Ahead

Sometime in late summer or early fall, an official ribbon-cutting and name-changing ceremony will take place. As included in the Water Resources Development Act of 2022, the lock will be renamed the John P. Murtha Locks and Dam to honor the late longtime congressman and decorated Marine Corps veteran from western Pennsylvania.

Frost said functional integration system testing began around the second week of January and included filling and emptying the chamber a few times to verify that it is working safely. Representatives for the contractor have also run some of their own craft through the chamber to gain access to it to complete work.

The river chamber contract is considered 97 percent complete, Frost said. Any remaining items on the project are expected to be closed out in late June or early July. In addition to the enlargement of the riverside lock chamber, work at Charleroi has included extending the Charleroi dam stilling basin, inland river dredging and some public shoreline facility relocations.

Work At Elizabeth Next

The work at Charleroi is the second of three major projects that comprise the Lower Mon Mega Project. The first phase involved installation of a new gated dam at Braddock (Locks and Dam 2), replacing the former fixed-crest dam, before work shifted to Charleroi.

Once work at Charleroi is complete, the focus will move to the next phase of the Lower Mon Project, the demolition of Lock and Dam 3 at Elizabeth, Pa., to create a navigable pass. This will create one 30.3-mile pool instead of 12.3- and 18-mile pools between the Braddock and Charleroi locks.

Major work at Elizabeth is expected to begin the week of July 8, Frost said. Full removal of the dam and locks there is estimated to take about three construction seasons.

Joseph B. Fay was awarded the contract in August to breach the dam but cannot begin much of the site work until the fish spawn in the area is complete after June 30. The Corps is already working with the contractor on initial contract submittals, including safety and environmental plans, Frost said.

Breaching the dam will cause the water in pool 3, between Charleroi and Elizabeth, to decrease approximately 3.2 feet. Pool 2, between Elizabeth and Braddock, will rise approximately 2 feet.

Controlled demolition is being left open to the contractor’s means and methods, Frost said, and could take anywhere from three to 12 days depending on the weather and water conditions.

“The concern is that we ensure that the water levels equalize at a very controlled rate,” he said.

That rate must be carefully controlled, in part, because of mussels in the project area, he said.

No traffic will be allowed to pass between Braddock and Charleroi while the water level is equalizing, he said.

Impacts On Pool 3

Once the Elizabeth Dam is breached, industry in pool 3 may have to consider doing some dredging, Frost said.

“The lowering of pool 3 is a bigger concern for our industry stakeholders because of the access they may have to their loading and unloading facilities along the river,” he said.

The Corps has had meetings both with the general public and industry stakeholders about what to expect with the new water levels, which will vary depending on the specific location along the river, Frost said. He added that the work has included a lot of mapping and use of Geographic Information Systems (GIS) to anticipate the new water levels.

The landside chamber at Charleroi will be decommissioned once the dam at Elizabeth is breached as it will no longer be usable for navigation in its current state.

The Corps of Engineers determined it could capture 90 percent of the benefits of the project by expanding the riverside chamber and breaching the dam at Elizabeth without performing work to that chamber for now. Work to refurbish the chamber to allow navigation remains authorized by Congress, but the plan signed by the assistant secretary of the Army in 2014 defers work on the landside chamber until the 2050s.

The chamber will be made available more quickly for flushing debris or ice as conditions warrant, however, Frost said. He expected a contract to be put in place in the summer or fall of 2025 that will include placing struts across the land chamber’s downstream area and adding a stabilization berm to the downstream guidewall so that it can provide those services.

Caption for photo: A downstream view of the newly constructed lock chamber at the Monongahela River Locks and Dam 4 in Charleroi, Pa., taken on February 14. The U.S. Army Corps of Engineers is currently conducting fully integrated system tests on the new navigation chamber, which measures 84 feet wide by 720 feet long. The Pittsburgh District continues to adjust the system’s programming to prepare the lock to open for navigation later this year. The facility is part of the Lower Monongahela River Project, which includes locks and dams at Charleroi, Elizabeth and Braddock, Pa. The three locks experience the highest volume of commercial traffic on the entire Monongahela River navigation system. (U.S. Army Corps of Engineers Pittsburgh District photo by Michel Sauret)