An artist's impression of the ventilation stack under construction on Great North Road as part of the Waterview Connection project.
It won’t just be the tunnels and the giant interchange at Great North Road that will attract attention when the Waterview Connection project opens to traffic in early 2017.
A giant ventilation stack to remove exhaust emissions from inside the tunnels is starting to take shape alongside Great North Road at the project’s northern end.
Instead of a conventional design, architects have designed an egg shape that sits on a ten-degree lean.
The base structure will stand 15m tall and will be finished by early October.
Bronze-coloured steel fins will then be installed to wrap around the stack.
An ever-changing kink fabricated into each fin will give the illusion of a spiral.
As well as providing an eye-catching addition to the landscape, the stack has a practical use. It will disperse vehicle emissions from inside the tunnels.
The air will be pushed by giant jet fans into a ventilation building along a 90m ventilation tunnel under Great North Road before being ejected.
This means better local air quality than the same traffic volumes using local roads.
Air quality monitoring will be carried out before the Waterview tunnels are opened to ensure they meet the air quality standards.
Find out more about the Waterview Connection project