On my way through Calgary back in October, I'd seen some workers casting concrete and making forms in a huge pit in the ground. Under construction was a new storm sewer line- complete with a massive outfall structure, big sections of RCP, and some strange box-like chambers. From outside the flimsy construction fences, it was hard to tell exactly what the finished product would look like, and I knew I'd have to come back and check it out eventually.
Fast forward five months to another Calgary road trip. This time I had arrived with draining in mind, and the newly-minted Black Curtain was on my to-do list. Kaos and Fyrephreak were my accomplices of the day, and we'd invited Nimrod and Defective along. The five of us met atop the huge outfall, which was nearly full with ice. Kaos led the way to a secondary outfall nearby, and Fyrephreak held open the gate as we all scurried inside. This duct pipe was a wide backbreaker, and we were all bent in half as we hurried upstream. Luckily, there were frequent manhole shafts where we could stand upright for a moment before moving on to the next one.
After passing through a couple square manhole chambers, we entered a larger pipe that lead into a junction room. On the advice of Kaos, I followed an RCP up to a small manhole chamber. The bare chamber, dubbed the "Satan Room" simply because of its five-sided pentagram shape, was quite small and obviously older than the pipe we'd walked through minutes before. I shot a few photos before going back to the junction room.
Fyrephreak took the lead up another branch of RCP that quickly brought us into another, slightly smaller, junction room. The concrete walls still looked new, and I realized I was in one of the chambers I'd seen the workers building last fall. To my right, a bright spot of daylight could be seen 50m away down a large RCP. The others hurried down toward the daylight, but I stayed behind in the room for a few minutes to shoot some photos before following them.
The large RCP terminated in a narrow, rectangular skybox, with a roof of grated metal. The pipe was about two feet above the ice-covered floor, and only two other small pipes opened into the room. The place had the curious title of the "Anti-Gravity Room", which was explained shortly after I arrived. Given the placement of the huge RCP, it was possible to shoot some neat photos (see below).
After we'd goofed around and shot many photos, we retreated back into the drain. We crossed through the junction room, and followed the flowing water into the RCP on the opposite side. This pipe was also quite large (about 2400), and had a great, reverberating echo. We entered an interesting manhole room that was hooked up to a "Vortex"- some sort of stormwater cleaning structure that sat next door. Heading downstream, the air started to get colder, and eventually ice began to appear on the water's edges. The ice trails quickly grew to a thick layer that covered the bottom of the drain, and we were forced to walk across the slippery surface.
A few minutes later, we began to see faint light, which grew to blinding intensity after we rounded a corner and caught sight of the outfall. Here, the RCP slants sharply down into the river, and had it been summer, the pipe would have been flooded to a level above our heads. Thankfully, winter still had the river in its grip, and the ice was more than thick enough to support our weight as we walked to the outfall. Crouching the last dozen meters or so, we sat atop the ice in the outfall for a few minutes looking out on the river. After a few quick group photos, we scurried out into the sunlight, desparate to warm our chilled limbs.
Overall, a short but very interesting drain. Several neat features, dual outfalls, and different periods of construction combine to make this a very enjoyable drain to visit.