One of two large stormwater detention ponds constructed between the ramps of the 427-409 highway junction


Stormwater management system added to the 427/409 interchange

The last decade saw the reconstruction of Highway 409, the short stretch of divided, multi-lane highway that connects Highways 401 and 427 with Toronto's Lester B. Pearson International Airport. It may have been during this rebuild, or sometime in the 1990s,  that two enormous stormwater detention ponds were built inside the interchange ramps at the 427-409 junction and additional tunnels added to the existing c. 1974 storm sewer that provides drainage for the portion of the 409 between the 427 and the bridge over Mimico Creek.

The large, sliding waterfall in Viceroy


Storm trunk sewer draining Highway 427 south of 401

Sitting on the east bank of Etobicoke Creek, on the very edge of Toronto, Viceroy's outfall is heavily fenced, abuts deep water, and when we explored it looked out on a show house belonging to Viceroy Homes Ltd., for which the drain is apparently named. For all I know, that housing project could very well have been completed by now, as I haven't since returned to this area.

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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.