Look back on our year of tunnelling

In 2021, Cross River Rail embarked on its year of tunnelling – an ambitious task that saw two massive Tunnel Boring Machines dig twin tunnels beneath the Brisbane River and CBD.

The two 1350-tonne mega machines – named after trailblazing engineer Professor Else Shepherd and pioneering feminist Merle Thornton – began their journey from the Woolloongabba station box at the start of the year and made their 3.8km journey underground, both emerging from the project’s northern portal at Normanby before Christmas.

Meanwhile, two 115-tonne roadheaders excavated the almost 900 metres of twin tunnels south from Woolloongabba to Boggo Road.

At the peak of tunnelling, more than 450 people were working on Cross River Rail’s twin tunnels, while 80 tunnel workers were able to complete an apprenticeship or traineeship.

Check out the video below, which summarises 12 months of tunnelling beneath Brisbane in under four minutes, as told through the lens of some of the media coverage the project’s milestone received throughout the year.

With tunnelling complete, the project’s focus shifts towards station fitout, with permanent station structures starting to take shape, and mechanical and electrical equipment installation commencing.


Cross River Rail tunnelling fast facts:

  • At the end of last year, TBMs Merle and Else broke broke through at Cross River Rail’s northern portal, having each excavated 3.8km of tunnel since launching from Woolloongabba in early 2021.
  • TBMs excavate the bulk (3.8km) of Cross River Rail’s 5.9km twin tunnels, with the rest excavated by roadheaders.
  • The TBMs have excavated 310,000 cubic metres of spoil and installed approximately 27,000 concrete segments to line the tunnel’s walls, each weighing about 4.2 tonnes.
  • At their deepest point, the TBMs tunnelled 58 metres below the surface of Kangaroo Point, and 42 metres below the Brisbane River.
  • Each TBM weighs 1,350 tonnes and is 165 metres long.
  • A crew of up to 15 people work in a TBM at any one time.
  • TBMs work at a rate of 20 to 30 metres a day.
  • Roadheaders excavated 85,000 cubic metres of spoil while tunnelling almost 900 metres from Woolloongabba to Boggo Road.
  • The roadheaders are 22-metres long and weigh 115-tonnes.