It is a lift bridge that has a clearance of 17.3 feet LWD when down. The last bridge before the lock is the International Railroad Bridge, 3.1 miles from the south channel entrance. It is a swing bridge which has a clearance of 17 feet LWD when closed. The signal for requesting the opening of this bridge is one long. The schedule for pleasure craft calls for the locking of downbound craft on the hour and upbound craft on the half-hour.
Commercial traffic has priority, however, regardless of the pleasure craft schedule.
For safety reasons, at no time will pleasure craft be allowed in the lock with tankers or large commercial vessels. In the absence of commercial traffic, the lockmaster may alter the schedule for the convenience of the small boater. As you approach the Black Rock Lock, you must inform the lock operators of your desire to pass and they, in turn, will indicate to you when it is safe to proceed into the lock. There are several methods of communication with the lock personnel, as follows. Channels 12 and 14 are working channels.