St. Lawrence Seaway convex bronze tablet stamped #6, set vertically on the west side of the lock, in the south corner of the support wall, 4.6 m east of the water level recorder, 12.32 m east of marker 58L9021. The marker is located 7.35 m from a beacon on a signpost, 2.13 m from the first mooring bolt, 0.69 m from the water's edge, 1.09 m from the southwest end of the concrete sidewalk and 6.45 m from the south corner of the water level recorder.
