Abstract: Employees #1 through #5 and three coworkers were removing and replacing steel roadway gratings and supporting beams on a leaf of a bascule bridge from which the machinery had been removed. The leaf could not be locked in the down position. The leaf was held in the closed position only by maintaining balance on the trunnions and by a single wire rope that ran from the rear of the counterweight to an uplift beam. The leaf suddenly and unexpectedly lifted, causing the employees to fall along or jump from the uplifting leaf. Employees #1, #2, and #3 were crushed and killed by the falling roadway grating. Employees #4 and #5 were injured either by jumping or being thrown from the rising leaf.