Passage is controlled by a lock keeper. The lock is situated immediately to the west of the Tuel Lane Tunnel, and boat crews are advised to wait beyond the tunnel until passage into the lock is clear, as the tunnel is subject to turbulence when the lock is emptying. Before the opening of Tuel Lane Lock, the deepest lock in Britain was Bath Deep Lock, on the Kennet and Avon Canal. This is numbered 8/9, because it replaces two original locks. In this case, a road widening scheme necessitated one lock which has a fall of .