Inner Route: The Hydroelectric Plant – From Sluice Gates to Plant Foundation

The innermost route (the one closest to shore) takes you through the Hydroelectric Plant built in the late 1800s. Water was directed from the canal into the plant’s headpond, then funneled into the turbine to create electric current for nearby transformers.

Here’s a sketch of Morrisburg’s plant with its inflow “headpond” and its outflow “tailrace” area. I have also shown the 1847 lock alongside it. At the level of the turbine, the water level drops 10-12 feet. So does the grassed area between the plant and the lock, with stairs between the two levels.


photo courtesy of

All of these areas are easily identifiable underwater if you know what to look for. The plant has been demolished and strewn about. The turbine is buried beneath the debris.

If you approach (see this post – it’s #4) by drifting close to the sloping north canal wall (that’s the one closest to the Canadian shore!) at 16-18 feet, you’ll start this section at the vertical wall leading to the gates. The arrow below marks the location.Lock Entrance Overview - My Sketch start of wall rotated 180

The end of the wall looks like a staircase up to the wall itself, which leads to the innermost sluice gate.

The three sluice gates mark the entrance to the headpond and they’ve weathered the years fairly well. With differing top boards missing, each has a distinctive look to let you know where you’re at.HE-Plant-Sluice-Gates---My-Sketch labelled-web

A walkway across large stone supports allowed workers to operate cranks fastened to the metal posts you see today. These opened the sluice gates to control water flow. The cranks are gone but they looked like this.

The cranks in these photos are located at Lock 25 in Iroquois. Much of that lock is still above water and if you wander around it you’ll see many of the mechanisms used in Morrisburg. Note the stone support structures.

Here’s a photo from showing the walkway and the cranks in Morrisburg. The upper gate of the Rapide Plat Lock is just beyond the walkway. The indentations you see in the support structures were called “drop slots”. Large wooden beams were dropped into them to provide protection from ice floes during the winter.

EPSON scanner image

Here’s what the sluice gates look like to divers today.

When you reach the gates you must go over them to get into the headpond. Use caution at the top as water flow is very strong and you come within 12-15 feet of the surface. The photos have been taken from both sides of the gates.

To get through the headpond, your next decision will be to either swim close to a wall or through the centre, ultimately reaching the funnel area where the turbines were. You’ll notice that the swim is not easy. There are fairly strong back eddies since river flow is obstructed, making it feel like you’re working against the current. Flow normalizes as you move downstream.

The stepped back ends of the support structures are easy to identify. Notice the hills of silt between them on the downstream side of the gates. If you’ve gone over the 3rd gate (southernmost), or swum over to it to approach the south wall, you’ll also see this circular item just inside. It is an important landmark because if you’ve been travelling another route and been “blown off course” it lets you know where you’ve ended up.

Choice 1: Some divers prefer to travel along the top of the north wall and then along its 45-degree angle leading to the plant.

Choice 2: Some divers prefer to swim to the south wall and follow it along the bottom until it angles to the right at the plant.

You can pull yourself along the ground. You’ll feel a bit like you’re going uphill but it’s actually all the plant debris that has been dumped into the headpond, including many bricks and boulders. Ahead of you is a concrete wall.

Power house Lock 23 old photo

The plant’s foundation rests on top of this wall with loads of bricks all around. You know you’ve reached it when you see the concrete in front of you and these capacitors lying on the ground. The photo on the right is a contemporary shot of capacitor locations in overhead wiring. Refer to the first diagram at the start of this post to see where they would have been located on land in Morrisburg.

Plant debris is strewn everywhere, including boulders and bricks on the bottom and bricks all over the walls.

Move on to the next post to see what lies beyond the plant foundations.