As part of the Expansion Project, Trans Mountain is constructing a 2.6-kilometre tunnel to connect Burnaby Terminal and Westridge Marine Terminal.

The start of tunneling is a milestone for the Expansion Project and represents one of the major components of construction in the Lower Mainland. Tunneling began at the Westridge Marine Terminal on May 26, 2021, following a year of preparatory activities and more than six years of planning, design and regulatory processes related to this portion of the Project.

The new tunnel, at more than four metres in diameter, will contain three 30-inch delivery pipelines to load vessels at Westridge Marine Terminal.

The tunnel boring machine was manufactured specifically for Trans Mountain from Herrenknecht in Germany. There will be seven workers operating the machine, and the tunnel boring is expected to take 200 days to bore from end to end.