The U.S. Army Corps of Engineers Pittsburgh District continues demolition and excavation within the dewatered river chamber at Charleroi Locks and Dam on the lower Monongahela River in Pennsylvania, Oct. 19, 2021. The Pittsburgh District recently finished building the new lock chamber walls and has emptied it of approximately 20 million gallons of water, a process called dewatering, to allow contractors to begin adding the mechanical inner works of the chamber. The new lock chamber is 84 feet wide by 720 feet long, which will allow a nine-barge tow to lock through in 25 minutes, something that would take more than two hours using the older, smaller lock chamber. (U.S. Army Corps of Engineers Pittsburgh District photo by Michel Sauret)