Yonge North subway alignment tweaked so that tunnel travels under fewer homes in one Toronto neighbourhood

The revised route for the Yonge North subway extension is shown. (Metrolinx)

The proposed alignment for the Yonge North subway extension has been altered in response to feedback from residents in a Thornhill neighbourhood who were concerned about the tunnel running underneath their homes.

Metrolinx CEO Phil Verster announced the changes in a statement released on Wednesday afternoon.

He says that the route will now travel underneath Bay Thorn Drive “wherever possible” rather than a corridor to the south where there are a higher number of homes.

“The previous route went under 40 homes and an additional 23 properties, whereas the new route goes under 20 homes and 15 additional properties,” Verster said.

Verster said that the changes to the proposed alignment for the eight-kilometre, $5.6 billion extension are in direct response to concerns raised by residents in the Royal Orchard neighbourhood of Thornhill.

He said that Metrolinx will also bury the tunnel deeper underground where it travels through the neighbourhood, with a minimum depth of 21 metres and a maximum depth of up to 50 metres.

“While we already expected that noise and vibration levels would not be significantly different to what residents experience today, these refinements will make them even lower,” he said in his statement. “In fact, early environmental studies based on the new route show that by using the proven technology available, noise and vibration levels from operations will be so faint in the Royal Orchard community that they’ll be practically imperceptible to human senses,”

Construction on the Yonge North subway extension is expected to begin in late 2023. The province has said that the project could be completed in 2030.