An ersatz diversion structure within the overflow portion of the Garrison Creek Sewer (1885). The small egg shaped pipe is the Asylum Stream sewer (1891), which in dry weather is routed through a metal duct into the pipe mounted on the right side of the main conduit, which runs south to Wellington Street where it connects with the beginning of the Low-Level Interceptor (1912).

Garrison Creek Sewer (overflow)
The overflow portion of the Garrison Creek Sewer

What is now exclusively an overflow was simply the lowest reach of the Garrison Creek Sewer when the city buried the Garrison Creek in the mid-1880s, and served in this capacity for twenty-five years until Toronto finally constructed an interceptor sewer system in 1910-1912.

In the relief sewer, west of Trinity-Bellwoods. The square ducts on the left wall come from an adjacent overflow chamber, where a tributary sewer that runs from Brockton Village can overflow into the relief.

Garrison Creek Relief Sewer
Arched sewer built c.1912 to relieve the original Garrison Creek Sewer south of Dundas St.

There are great, arched, empty spaces beneath the old City of Toronto, and the Garrison Creek Relief Sewer is one of them. Completed around 1912 along with the city's first interceptor network and the new Garrison Creek Sewer to the north, it served to expand the capacity of the existing Garrison sewer system by providing a second outlet for the watershed during periods of high flow.

A beautiful junction where small round red brick pipes from Hamilton's downtown core transition to the large concrete arch that typifies the Wellington St. Sewer's downstream reach.

The Duke of Wellington

Winding beneath Hamilton's downtown core, the Duke of Wellington, the brick and concrete Wellington St. Sewer, is arguably the ark of Hamilton drains.
Red brick and concrete arch tunnels lead from downtown Hamilton to steel plant harbour

Winding beneath Hamilton's downtown core before straightening beneath Wellington Street to head for an outfall in the harbour, the Duke of Wellington, the Wellington Street Sewer, is the Ark of Hamilton drains. Documented in Hamilton Spectator articles in both 1923 and 1973, the conduit is easily one of the most beautiful sewers in Ontario, built competently in a range of styles and materials.

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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.