CAUTION - LIFTING TRAIN BRIDGE CLEARANCES
Bridge span is normally in open position, displaying flashing green signals for water traffic movement. As a train approaches, signals go to flashing red, siren gives four blasts, pauses, and repeats four blasts, etc. After eight (8) minutes delay, the bridge lowers and locks if scanning equipment reveals nothing under the bridge. When the train has cleared, the bridge span raises and signals go to flashing green for water traffic. For lifting bridges, whose spans do not open to a full upright orvertical position, unlimited vertical clearance is not available for the entire charted horizontal clearance.