Canal lock in Sg.Besi

Canal locks are mostly in Europe, and there's of course the big locks in Panama Canal for the very big ships to pass through. Now I know there exist a lock in Sg.Besi.
Apparently there's a 7m difference in water level between the North & South Lakes (or is it East-West?!) so the boat from the Mines Shopping complex need to go through the lock to get to the bigger South lake & on to the Palace of Golden Horses. The 1hr round trip from the Mines Shopping Complex to the hotel and back costs RM28/per head.