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

Bluffer's Park Overflow Sewer

Pipe leads to small arched conduit leads to CSO dropshaft

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.

Rosedale Creek Sewer Overflow

The concrete tunnel pictured on the cover of Ondaatje's "In the Skin of a Lion"

Pictured on the cover of Michael Ondaatje's extraordinary novel In the Skin of a Lion, the overflow tunnel for the Rosedale Creek Sewer remains unexplored.

The Parkside Relief Sewer begins at abandoned stand-by tanks in the northeast corner of High Park, which once served to provide temporary storage relief for the High Park and Earlscourt Trunk Sewers.

Parkside Drive Relief Sewer
Built c. 1910-1912 to relieve sewers in Earlscourt and north of High Park, the Parkside Relief Sewer continues to serve as the western-most overflow sewer for both the High-Level and the MTI. While overflows from Parkside are now intercepted by the Western Beaches Storage Tunnel, the recent sewage overflow into Budapest Park calls into question the success of that expensive infrastructure addition.
Built c. 1910 to provide relief for the High Park Storage Tanks

The Parkside Drive Relief Sewer was built c. 1910-1912 to relieve the west end of Toronto's High Level interceptor (built concurrently) and the High Park, Junction and Earlscourt neighbourhoods that lie upstream in the sewershed. While active use of the stand-by (storage) tanks at the top of the sewer was discontinued in the 1970s with the construction of the Mid-Toronto Interceptor, the Relief Sewer continues to serve as the top-most overflow sewer for both the High-Level and the MTI.

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Michael Cook is available to speak to your organization about infrastructure history, lost creeks, current conditions, and opportunities for change in our management of and communication about urban watersheds, and to work with teams proposing or implementing such change. Get in touch.