The HE Plant Route: Best for Novices

Over the years we’ve guided novice divers through Lock 23 in a number of different spots and have generally concluded that the easiest is the innermost route leading to and through the remains of the Hydroelectric Plant.

Hydroelectric Plant

This route is best for novices for several reasons:

  • It has no current to cross over during the approach drift to the locks.
  • It has the least current within its “own” area alongside the locks.
  • It’s closest to shore, which makes the exit swim the shortest.
  • It’s the shallowest – maximum 35-38 feet.
  • It has some of the most obvious landmarks.
  • It has lots of interesting and different “stuff” to see.
Headpond, HE Plant

In this post I’d like to focus on the distinct landmarks within the headpond and up to the wall where the plant’s single turbine was located (but now buried beneath the rubble of the demolished building).

I mentioned the structure of the sluice gates in my last post. They all look the same and it doesn’t matter which you go over to get into the headpond. Notice that although the backs of the supports between gates look like staircases, they’re simply the rear structure of the supports.

back portions of sluice gate supports

(1) On the floor of the headpond at the northernmost (closest to shore) area just inside the sluice gates is one of the old cylinders from the electrical transformers, seen vaguely in this photo.

transformers HE plant

Here’s the cylinder – taken in 2016. I need to see if it’s still visible this year.

transformer cylinder
transformer cylinder location

(2) On the floor of the headpond at the southernmost area just inside the sluice gates is a larger concrete ring. I don’t have any idea what it is but it’s the only one. Thanks to Bill Wyman for the photo.

concrete ring
concrete ring location

(3) As you move through the narrowed area towards the foundations of the building housing the turbine, you’ll quickly see how the building was constructed… bricks!

bricks
bricks location

(4) In amongst the bricks (but set apart by divers so they’re more noticeable) are some capacitors/insulators normally found on the top of electrical poles like the ones shown below.  While bricks may be seen here and there… capacitors are only found in this part of the HE plant.

capacitors/insulators
today’s capacitors
capacitor location

Once you reach the wall at the end of the narrow portion of the headpond, you have found yourself at the HE plant building. You’ll ascend the wall, take a look at the brick structure, then descend and drop another 12 feet to the tailrace portion of the plant.

HE Plant building foundation

Here’s what it looked like long ago.

HE Plant circa 1850

As with all landmarks, what makes these useful is that as soon as you spot them, you know there’s only one place you can be!

Sydney