Metrolinx underpinning explained

The station at Yonge and Eglinton for the new Crosstown LRT is going to be the largest built on the new transit line.

But the biggest challenge, is the subway that will be passing overhead, while workers dig below.

There are no plans to halt the subway, so engineers have come up with an under-pinning system, that keeps the subway tunnel and track in place to within 3mm, or about the height of a piece of rice laying on its side.

When completed, at 269 metres, the station will have the largest excavated footprint of any other station on the line.