The hard to find Outfall 904, gateway to the short, weird tunnel that is the Bluffer's Park Overflow.

Bluffer's Park Overflow Sewer

Cliffside/Cliffcrest CSO

Construction Details:
Small arched conduit of unknown age; 2000mm oddly-shaped RCP installed c. 1974 when the first phase of Bluffer's Park was built from artificial fill by Metro Toronto. The launch facilities and marinas were added in the 1980s.

Also Known As:
Ninj's Bluff

This is a small overflow sewer beneath the Scarborough Bluffs that carries a bit of groundwater or retained stormwater but based on the smell and look of the water must serve as an overflow point for a combined sewer on top of the Bluffs.

Back in 2004, the late, great Ninjalicious pointed me in the direction of this outfall. At the time, he was no longer exploring drains. He was happy to tell me where to find this one, although his enthusiasm was tempered by the fact that it appeared to be within the area of the city served by combined sewers. Undaunted, I figured out how to take the bus out to the top of the Bluffs, and headed down the hill to the strange mix of giant pickups towing speedboats and family picnickers that is Bluffers Park.

The outfall is surprisingly difficult to spot, despite the tell-tale chainlink "outfall fence" that encloses it on the landward side. Scrambling down to the shoreline, one finds that the short channel leading from the portal to the lake is choked/protected by an army of rough-hewn concrete slabs. The opening itself was barred, but a couple of those bars had conveniently fallen out of their frame, making Outfall 904 a reasonable squeeze.

The concrete tunnel inside is a perfectly normal RCP, but the for some reason the actual opening has a strange "flattened egg" shape. Rounding a couple bends, you quickly reach a small access chamber that marks the transition between the round concrete pipe, put in during the mid-1970s when Metro Toronto used landfill to create this park, and the older, smaller arch tunnel upstream. In 2004, this chamber and access shaft was also notable for missing its manhole collar (the lid strangely was there), though I imagine the intervening years have seen that oversight or theft rectified.

For some reason, back in those days I was actually willing to push through a ridiculously tight space like that present in the arched conduit, a stoop made worse by the metal brackets attached to the ceiling that had once held in place an electrical or telephone cable. Those brackets, left in place after the cable was removed, now reach dangerously down towards anyone foolish enough to stumble through this tunnel. At the end, there's an impassable drop shaft raining CSO mist down through the darkness into the dark conduit -- not exactly a pot of gold or a pirate ship.

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