Strange pipe elbows in the Vault, probably connections from the adjacent industrial building at 606 Aberdeen.

The Vault

Disused tunnel once carried Chedoke Creek tributary, now only drains creek's former draw

Something of a relic, the creek drain we call The Vault was built early in the last century to facilitate residential development and the construction of the old ELCO/Hamilton Metals building on Aberdeen. At the time, the drain would have enclosed a Chedoke Creek tributary at the eastern edge of Chedoke Golf Course. Later, Public Works engineers must have found it necessary to provide more capacity for this creek (perhaps because enclosure and development on the Mountain had unleashed larger storm flows down the ravine upstream of here).

The lower set of stairs, about a hundred metres inside the outfall of the Chedoke-Aberdeen Creek Sewer

Stairway to Paradise

Fascinating creek sewer includes two enormous flights of concrete spillway stairs

The Stairway to Paradise as we call it, or the Chedoke Creek Diversion Sewer, is an incredible drain that runs downhill from the Chedoke Radial Trail into the Chedoke Creek Valley and the creek's now-canalized main stream, with the mouth of the drain visible to tens of thousands of commuters passing everyday on the 403 Highway that now occupies the valley. Having to contend with a large elevation change between the base of the Niagara Escarpment, where the drain begins, and the bottom of the valley, the sewer's builders included a pair of massive staircases within it.

Access chamber, probably beneath the York University common. Note the unusual placement of a chain across the downstream pipe -- there is no drop or other hazard here.

Tentanda Via

Small concrete storm sewer drains the 1960s portion of the York University campus

There isn't much to say about the main storm sewer beneath the York University campus. Built c. 1963 to drain what would soon become Toronto's second major university, it's a round concrete pipe that is never larger than about 1800mm, and soon shrinks to more uncomfortable diameters. Running roughly west-southwest from the vicinity of Winters College, it passes beneath Vari Hall and the Ross Building before outfalling into the east side of Stong Pond.

The hidden outfall of this storm trunk almost seems cut from an earlier age in Toronto's building history, embellished as it is with engraved depth markers in roman numerals.

Roman Numerals

1970s concrete storm sewer drains fuel terminals and industrial park E. of York University

Found deep in an overgrown floodplain southwest of North York's G. Ross Lord Reservoir and Dam, the outfall for the Dufferin Creek storm sewer is one of the city's more ornate drainmouths. Surrounded on two sides by industrial parks and on a third by the grounds of the City of Toronto's Chesswood Drive Transfer Station (and former incinerator), the outfall is also perhaps one of the more difficult to find in the city, a mystique that is heightened by the roman numerals engraved on a retaining wall beside the opening.

This junction chamber is where the Morningside and Malvern storm trunks meet before running down into the Morningside Creek ravine.

Wimpey Morningside

1970s large-diameter RCP trunk storm sewer network in outer Scarborough

Wimpey Morningside takes its name from the builders' marks on pipe segments throughout the storm conduit -- two conduits actually, "Wimpey Morningside" and "Wimpey Malvern," which come together before running east into the ravine of Morningside Creek.

An access chamber deep inside the North Toronto Storm Trunk Sewer, which drains the area of Glen Park, Lytton Park, and Lawrence Manor.

North Toronto Storm Trunk Sewer
Another Metro-built trunk storm sewer from the 1960s

The North Toronto Storm Trunk Sewer is another Metro project installed during the 1960s and 1970s. Like many of the others, it helped to improve sewerage along the route of the planned Spadina Expressway, but like the North York Storm Trunk Sewer further west, its main purpose was to allow partial sewer separation in boroughs served by smaller sewage treatment plants, and to open up additional land for residential development.

Looking towards the outfall in the Wilson Heights Storm Trunk, beneath the slopes of Earl Bales Park

Depths of Salvation

Northernmost of the Spadina Expressway storm sewers built by Metro

The Wilson Heights Storm Trunk Sewer and its sewershed stretches from the W. R. Allen Road (formerly the Spadina Expressway) and the Downsview Airport lands east to the West Don River at Earl Bales Park.

The corrugated metal section of this drain is coated with a thick, rubbery tar, apparently intended to increase the lifespan of what is by now a notoriously bad material for building large sewers.

Westview Greenbelt
Large conduit built 1960s by Metro to relieve sewers near the Spadina Expressway

The North York Storm Trunk Sewer is an extensive sewer built by Metro in the late 1950s and early 1960s to relieve combined sewers in the southwest corner of North York and to drain a portion of the Spadina Expressway. It had the effect of redirecting a large portion of stormwater from this area, which would have previously flowed southeast into Don River tributary creeks, into the Black Creek and Humber River system. Its construction was contemplated as early as 1949.1

  1. 1. Gore & Storrie. 1949.

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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.