Ontario, Toronto to build new electricity transmission line to power city's downtown

Toronto is getting a third electricity transmission line to help power the city's downtown and replace aging infrastructure. 

The project will help support the city's growth and major transit expansions like the Ontario Line while making the city's electricity grid more reliable, said Stephen Lecce, minister of energy and mines, at a news conference Wednesday morning.

"Today is about planning ahead, about doing the hard work to make sure Toronto has the energy infrastructure needs, not just for today, but for decades to come," Lecce said. 

Toronto's electricity demand is expected to roughly double by 2050, with the greatest need coming from the downtown core, the province said in a news release. 

"That's not just because we're building new homes or the Ontario Line. It's because of the electrification of vehicles, of heating and industry," Lecce said. 

"It's because this city is a magnet for towers and investment and economic growth."

3rd line needed to keep up with demand 

Ontario's Independent Electricity System Operator (IESO) has determined that the city will need a third transmission line in order to keep up with demand. 

The city currently gets its electricity through two transmission supply paths: one from the west at Manby Transmission Station near Kipling Road and Dundas Street, and one from the east at Leaside Transformer Station near Overlea Boulevard and Millwood Road.

Those transmission lines will start to reach their capacity in the early 2030s, the news release says. 

The IESO is expected to make its final recommendation to the government on where the third transmission line should be built by August, after which the Ontario government will determine when construction on the project could begin. 

The transmission line could take between seven to 10 years to complete, Lecce said. 

The IESO has identified three potential options for where the new transmission line could be built: 

• An overland route from Pickering to Leaside in Toronto.

• An overland route from Pickering to the Port Lands in Toronto.

• An underwater cable from Darlington or Pickering to the Port Lands in Toronto.

The IESO will be consulting with the City of Toronto, Indigenous communities, key stakeholders and the public over the summer before it makes its final recommendation on the best option for the project, the news release says.