Wednesday afternoon traffic was moving slowly through the intersection of Route 8 and Mercer Road in Center Township after two tractor-trailers took out power lines for the five traffic signals at the busy crossroads. A truck pulling an oversized load north on Route 8 hit a signal causing other lines to sag, said Greg Brewster, township street department foreman. A second truck struck one of the sagging lines when it turned left from Route 8 north to Mercer Road, Brewster said. The accidents didn't cause a general power outage, but power to the signals was shut off for a while.