A towboat pushes eight barges of coal along the Monongahela River south of Pittsburgh, Jan. 30, 2023. Each barge can hold the same amount of material as 70 large semi-trucks or 16 rail cars. The U.S. Army Corps of Engineers Pittsburgh District operates 23 locks and dams on the Ohio, Monongahela, and Allegheny rivers, saving industries approximately $4 billion in transportation costs annually compared to using other means such as trucks or rail. The Pittsburgh District is known as the “Headwaters District” because the Ohio River starts at the point where the Allegheny and the Monongahela rivers converge. The Pittsburgh District offers the beginning of navigation for much of the nation, both geographically and historically. (U.S. Army Corps of Engineers Pittsburgh District photo by Michel Sauret)