Digging done as second massive machine wraps up tunnel work on Mississauga LRT line

The second of two massive tunnel-boring machines tasked since 2022 to dig out the underground portion of a new light-rail transit line in east Mississauga and Toronto has completed its job to mark the latest milestone in the major public transit project.

Having set out on the journey from its launch shaft in Mississauga to begin the daily digging job in April 2022, the TBM dubbed Renny emerged from the fully-dug tunnel on May 22 in west Toronto to move the Eglinton Crosstown West Extension LRT initiative one step closer to completion.

Renny’s subterranean partner, Rexy — the two were named as a nod to areas in Mississauga and Toronto — completed its earth-moving trip on April 26. Though it was launched into action some three months after Renny in late July/early August of 2022, Rexy was first to complete the task.

“Renny the tunnel-boring machine has broken through the final wall to complete a two-year tunnelling journey,” project leaders with provincial agency Metrolinx said in a post to social media last week.

Officials said the TBMs, built in Germany and brought to Canada in early 2022 before going into the ground a few months later, each travelled 6.3 kilometres in finishing their underground work.

The massive TBMs measure 131 metres long and weigh 750 tonnes, according to Metrolinx. They moved eastward from Mississauga at 10 to 15 metres per day.

The digging machines will now be disassembled, said Metrolinx officials, who initially hoped the TBMs would reach their final destination late in 2023 or earlier in 2024.

The names Renny and Rexy reference Renforth Station in east Mississauga and the Rexdale neighbourhood in northwest Toronto located adjacent to the ECWE.

Map shows the route taken by the two TBMs.

The Eglinton Crosstown West Extension is a 9.2-kilometre above ground/underground LRT route that will take the Eglinton Crosstown LRT in Toronto farther west and “bring much-needed rapid transit to Etobicoke and Mississauga,” project leaders said.

When completed in roughly seven years, it will link east Mississauga and likely Pearson Airport as well with parts of west Toronto. With project completion anticipated by 2030-31, the new route will bring the Eglinton Crosstown LRT line from Toronto west to Renforth Drive in east Mississauga.

A proposal to extend the ECWE an additional 4.7 kilometres from Renforth Drive to Pearson Airport in Mississauga is also being strongly considered.

When finished, the ECWE will operate underground from Renforth Drive to just west of Scarlett Road in Toronto, where it will then transition to a 1.5-km elevated section that runs east of Jane Street before heading underground again and connecting to the future Mount Dennis Station.

The new LRT line is expected to cut greenhouse gas emissions by some 39,000 tonnes each year, project leaders say.