Watch the video below, which outlines the basic process and timeline of designing and delivering the Toowoomba tunnel.
Here’s an accompanying 3D model of the proposed tunnel that was created by the Inland Rail team. Spend a couple of minutes navigating the model to visualise what it will look like and what additional safety features it has...
One of the most complex yet common challenges in a project like this one is that rail lines have to be extremely flat. As surveyors bring their assessments in, you'll discover that the Toowoomba ranges are anything but – full of hills, valleys and floodplains, they present a significant challenge to engineers whose jobs it is to get a train moving smoothly and safely along this part of the alignment.
Check out the video below, which details why trains struggle to go up steep gradients 🚂 ⛰
If you can’t go over the hill, then your best option is to go through it. Rail tunnelling is used to effectively punch a hole through the hill at a flat alignment. This process is highly complex, and involves moving lots of materials, making cuttings, and building embankments.