Most of the original machinery used to operate the lock is also still in place. Another unique feature of the site is the Sault Canal Emergency Swing Dam (orange), the only emergency swing dam left in existence, and the only one to ever be used in an emergency.

Emergency Swing Dam, located in Ontario, Canada.
It is the last remaining structure of its kind in the world.
The dam was built in 1896 by the Dominion Bridge Company of Montréal, Québec.
Its purpose was to control water flow and allow for critical repairs to the lock if a ship were to strike the locks.
The structure is designed to swing across the canal to reduce water flow when needed.