Shovels in hand, people contracted by the city will soon perform a complex and costly rescue deep under the streets of Toronto.

They won’t be freeing a raccoon from a sewer. Instead, it’s a “micro-tunnelling boring machine” stuck underground for nine months after accidentally chewing into buried construction waste.

If this was a Pixar film, the digger would have a cute name, a backstory rife with challenges, and a harrowing account of how its big break — tunnelling a storm sewer to help protect homes from basement flooding — went so awry.

Not only did it veer off course, it got stuck and dangerously destabilized the earth above it.

The city is just hoping to get the device above ground, finish the tunnel and learn from a $9-million reminder that the soil under Toronto is rife with unseen construction material, as well as utility cables, creeks and more.

The boring machine — cylindrical, about five metres long with a 1.5-metre-diameter “cutting wheel head” — was lowered into the ground a year ago at Old Mill Drive at Riverside Drive for a 282-metre grind route to just north of Bloor Street.

Being installed right behind it was a storm sewer to divert excess rainfall from homes in the Old Mill area, one of several flood-proofing projects being undertaken by the city as aging infrastructure is overwhelmed by increasingly intense storms.

The digger, tethered by cables, stayed mostly on course, chewing its way under the Line 2 subway tunnel to seven metres short of its destination when, on June 9 it hit “tie-backs” — steel wires left from foundation work on nearby condo buildings.

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