When in Doubt, Bring a Boat

Going on a subterranean cruise inside the remnants of Montreal’s waterworks system

Have boat, will travel.

When in Doubt, Bring a Boat

Going on a subterranean cruise inside the remnants of Montreal’s waterworks system

Here’s a bit of video footage from about a month ago near the LaSalle entrance to the aqueduct. I’ve been poking around this general area for about a year now, hoping to find something interesting related to either the former or existing water supply intake pipes. I haven’t had much luck with that yet, but while walking through the woods at the edge of the aqueduct, I stumbled across a manhole cover which led to a fairly large, but half-flooded chamber.


After climbing down a very rusty ladder to a narrow ledge, I lit the chamber up with a spotlight to get a better look. A second ladder, with even rustier rungs, was almost entirely submerged from the flooding. I couldn’t see the bottom. I saw an entry point for water along the  side of the chamber facing the aqueduct. On the opposite side of the chamber, two additional channels with ceilings sloping down towards the height of the water could be seen. It was difficult to tell if they were entirely submerged, though. I thought that maybe if the water level there was low enough it might be able to get a better look down through the length of them.

Overlooking a portion of the chamber from the ledge.

Not content with being unable to see everything from the vantage point of the ledge, I returned a few days later with my good friend nel58 and (what else?) a $10 inflatable boat from Canadian Tire. Actually, a pool-toy would be a more apt term for it. Either way,  it did the job— at least up until nel58 took it for a spin. Ten minutes later it sprung a leak. Whoops.

The water level ended up coming up to the very top of the two channels I was interested in so that ended up being a bust, too. I figure they both lead into the conduit that I covered in my previous entry. If that’s the case, then there’s a good chance that most of that portion is considerably flooded as well.

A view from the “boat.” The two channels that presumably lead into the water distribution conduit can be seen beneath the far wall.

So, all we could really do was go for a little cruise around the chamber using our “disposa-boat.” I can think of worse ways to spend an evening. The acoustics were fantastic and I imagine that during warmer months it would make for a nice little subterranean swimming hole. The water seemed clean enough for it. A variety of graffiti adorning the walls indicates that local kids have used the chamber for various activities in the past, but who knows if swimming was ever one of them.

What was the chamber used for originally? My theory is that it was added after the 1913 collapse of the water conduit. Up until that point, there was only one way water could enter the tunnel- through a small intake situated close to the shoreline of LaSalle. When a new intake system was developed to bring a cleaner source of water into the aqueduct itself, it probably made sense to have that same water be conveyed towards this chamber and  into the conduit. If ever it needed to be drained for inspection or repairs, then stop-logs could be added to serve as a temporary dam.

View of one of the two walled-off inlets found near the midway point of the aqueduct’s water conduit.

Similarly, near the midway point of the conduit explored in the last entry, there is another chamber that looks as though it was added around the same time and for similar reasons. There may be others that I just haven’t come across yet. It has two inlets/outlets facing the side of the aqueduct, both of which have been permanently sealed off. There may have been simple control gates here at one point. Another slot for stop-logs runs across the middle of the conduit, dividing the two channels so that if one length of the tunnel ever needed to be taken out of service, the remaining portion could still be used.

Video footage courtesy of nel58.