Members of the Society of American Military Engineers walk up the steps of a control tower while visiting the construction site at the Monongahela River Locks and Dam 4, operated by the U.S. Army Corps of Engineers Pittsburgh District in Charleroi, Pennsylvania, March 21, 2023. The U.S. Army Corps of Engineers Pittsburgh District operates the facility and has overseen the construction project at Charleroi to improve inland navigation in the region. Many of the visitors on the tour represent firms who provided contracts for the project. The newly constructed chamber is scheduled to fill with water before the summer, and it is planned to go into full operation in 2024. Construction at Charleroi began in 2004. Over a span of 20 years, the Charleroi project required 17 contracts and 20 designers. Once complete, the Pittsburgh District will begin removing the river dam at Elizabeth, Pennsylvania, to create one continuous navigable pool between Charleroi and Braddock, Pennsylvania. (U.S. Army Corps of Engineers Pittsburgh District photos by Michel Sauret)