In the late 1700’s, the St. Lawrence River was a fast flowing waterway dotted with troublesome rapids that hindered navigation. Construction began in 1834 on a series of Canals and Lift Locks that would link the Great Lakes to the Atlantic Ocean.
This monumental task of leveling out the river from sea level to the height of Lake Ontario was an astounding 243 ft (74m), and would take more than 10 years to complete. Since then, the system has seen several upgrades and expansions, but none greater than the Seaway Project started in the early 1950’s. This included the Robert-Moses Hydro-Electric Dam in Cornwall and several water Regulatory Dams to the west, this planned inundation submerged most of the Cornwall Canal to create a Head Pond upstream. A few miles of the Old Canal still exist (unsubmerged) downstream of the dam in Cornwall, running along 2nd Street West and Water Street before spilling back into the St. Lawrence River.
The entrance to the Cornwall Canal was located across the now submerged Village of Dickinson’s Landing just west of the once mighty Long Sault Rapids and Lock 21.
Topography Chart from 1955 for The Hydro-Electric Power Commission (pre-flooding). The blue outline shows the present day water level, green is land (islands of the St. Lawrence Parks), yellow is the road and causeways of the Long Sault Parkway. These precise charts depict all the locations of the buildings and dwelling, Dickinson’s Landing shown at the left of the chart. Note that the old Highway #2 runs up onto Phillpotts Island, the pavement is still exposed and leads out of the water.
The entrance of the Canal (looking East), the ship coming upstream will soon pass the Pier Head that supports the Lighthouse (seen just above the word “River”). The outer canal wall which is shown covered with a row of trees, was formally known as the “towpath”, where sailing ships would have had to be pulled through by a team of horses. Bollards were installed along the towpath as well as the Pier Head so that ships could tie off and wait in queue before Locking through. The Lighthouse was finally added in 1865, this 22 ft high wooden structure was able to safely guide vessels in from 3 miles away.
The Pier Head was 310 ft long and 20 ft wide at the top of its limestone blocs, which were acquired from a nearby quarry.
Before the inundation, the Lighthouse was moved and now proudly sist on the shore of the St. Lawrence River inside the grounds at Upper Canada Village Park. They also have an exact, full size, replica of it at the public entrance of the park.
Navionics Boating App, bottom relief chart of the river
Showing the towpath wall from the Lock 21 dive site (upper right Dive Flag) to the canal entrance (lower left), now known as Dickinson’s Lighthouse dive site (even though the lighthouse has been removed). The limestone Pier Head wall is the skinnier end of the towpath wall at the entrance of the canal.
This vast 200 year old structure is still mostly intact, considering it wasn’t designed to be totally submerged for the last 70 years.
Note that these sketches are not to scale
The perfectly beveled nose blocs are really a marvel of hand cut masonry (in photo), “LH” (in diagram) shows approximately the location of where the Lighthouse once stood.
8 x 8” wood beams forming Cribs filled with stones and rubble which support the Pier Head’s 3 x 6 ft limestone blocs. This tightly knit wooden foundation has started to unravel in a few sections, dozens of timbers have been pushed out by the elements and are strewn about. Beware of the loose pieces!
The best way to Dive Dickinson’s Lighthouse.
Drive your vehicle west of the Lock 21 dive site onto Phillpotts Island. Turn left on the unmarked gravel road midway on the island, which leads to the Old Hwy #2 paved road that disappears in the river. (I know this reads like a Google Maps nightmare!) Park your vehicle near the water and get the gear ready.
Orange dotted line, driving to the entry site
If diving with a scooter (DPV), you may head in from this point and go south. It is a fairly shallow ride to the drop wall of the canal and you may have to contend with long weeds along the way. Crossing the canal bottom will bring you to the outer wall (towpath) where you will follow it upstream (west) until the Cribs or Blocs appear, depending on your depth.
Non-scooter divers will gear up and walk on the old pavement in the water to the tip of Vankoughnet Island, carrying your fins (red dotted line on the satellite shot). Keep in mind that there is a break in the asphalt part way in, but keep a straight line and the pavement reappears. Once you’ve reached the point, dawn your fins and back kick surface swim till you see the drop off of the canal wall. While swimming, try and steer south/west as the current will drift you east. Once you drop, head south and start to cross the canal (45-50 ft depth) to the outer wall (towpath), then follow it west to the cribs/bloc wall. Use the rocks and bottom to help pull yourself along, the current can be strong.
You can explore the full length (310 ft) of the Pier Head as well as from top to bottom, a few guide ropes have been set and can be used to pull yourself along. The most impressive part of this site is nose of the Pier, where the Lighthouse stood. The massive blocs are perfectly puzzled in place and shaped to divert fast moving water as well as withstand Canadian winter ice flows. It is now time to consider the 2 choices we have to head to the Exit point. Option 1- from the Nose, turn with the current and head east to explore the other side of the Pier Head viewed from the old river bed. After passing the last crib/blocs you can veer north to the shoreline.
Option 2- from the Nose, head north/west crossing the canal opening till you reach the inner canal wall and follow it east with the current for a bit then return to shore to the exit point.
Marc Pilon, Andrew Emard, Sam Hamed, & Jason Xenakis