The U.S. Army Corps of Engineers Pittsburgh District is adding navigation safety signs and buoys upstream and downstream of Monongahela River Locks and Dam 3 to warn boaters and industry of hazardous conditions during upcoming demolition of a 107-year-old dam. The signs will be in place on the river 1,500 feet upstream and downstream of the fixed-crest dam by June 21. The first demolition to breach the dam is scheduled for July 10. (U.S. Army Corps of Engineers Pittsburgh District graphic by Dan Jones)