The massive tunnel boring machine that will be used to dig the tunnels at Waterview has been officially handed over to the companies working on the project. When looking at pictures, it can be hard to realise just how big this thing will be. The machine is enormous, with the cutting head measuring 14.5m wide and the entire machine just under 100m in length. The NZTA say it is the 10th largest of its kind every built. I’m hoping that we well get a chance to have a look at it up close before it starts eating its way underground.
You can read more about it in the NZTAs press release.
And another image of it
I know that many people that read this blog aren’t supportive of new motorways however I do like the project. I can see the new connection being very useful for a lot of people. Perhaps more importantly I hope that long term it represents the final major motorway project in the city, after which we can properly focus all of our efforts on improving alternative options.
I know some have also questioned if the TBM can be used for other projects, like the CRL. The answer to that is no. After a project these machines are normally worn out. Also the Herald reports this morning that the NZTA have sold the machine back to the manufacturer after the project for 20% of its purchase price of ~$50m and they will reuse some of the parts. There is another factor too, this machine is much larger than what we need for the CRL where the TBMs are proposed to be around 7m in diameter. Even digging two tunnels, like what is proposed for the CRL, it would likely be much cheaper than than using one giant one due to there being less than half the amount of rock to have to deal with. The image below shows the surface area of the Waterview TBM in blue with the proposed the CRL tunnels in grey.
And finally, if you don’t know how these machines work, here is a video