While the situation on Melbourne’s streets continues to evolve, below the surface Rob Carr grapples with its own challenges, using its microtunnelling expertise to overcome any obstacle.
The sewer network in Melbourne’s CBD is approximately 120 years old and is relied upon by a rapidly expanding population, with Melbourne’s entire population now closing in on 5 million. To ensure this vital network can cope with the needs of the reliant homes and businesses, City West Water (CWW) appointed civil construction and tunnelling expert Rob Carr – in association with design partner SMEC – to complete the Lonsdale Street Sewer Upgrade.
The project is the second stage of a four-stage strategy to install a secondary 900 m long sewer line under Lonsdale Street, with Rob Carr to deliver a DN 1400 glass fibre reinforced plastic (GRP) sewer line using a microtunnel boring machine (MTBM) for its construction.
After launching the MTBM from its 23 m deep launch shaft on William Street in early 2020, Rob Carr completed its first drive of approximately 550 m. The machine has now been turned around and commenced jacking on the second line, which is to be 350 m long.
Rob Carr is also simultaneously completing a new 23 m tunnel into Elizabeth Street using a hand jack, which will be tied into an existing manhole at that location.
Above the surface
While the tunnelling operations continue to run 24 hours a day, six days per week below the surface, Melbourne’s above ground situation continues to be impacted by the COVID-19 pandemic. After briefly easing restrictions, several virus outbreaks in Victoria have forced residents to return to strict lockdowns and once again increase prevention measures.
Rob Carr and CWW have been adhering to all coronavirus prevention guidelines onsite, allowing the project to continue running at full power. Border closures have forced some interstate workers to remain in Victoria, but Rob Carr Construction Manager Andrew Scarr says everyone involved has been able to deal with the changing conditions.
“It has an effect, but we have managed to work around any of those challenges,” he says.
“Later this year we hope to complete the line we are constructing at the moment, tie into the manhole on Spencer Street and complete the manhole at the launch shaft.
“The project has had its challenges, but we’ve continued to move forward and are steadily delivering these sewer upgrades.”
Rob Carr aims to complete its works later in 2020.
This article was featured in the September 2020 edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet or mobile device, click here.
For more information visit the Rob Carr website.
If you have news you would like featured in Trenchless Australasia contact Assistant Editor Sophie Venz at svenz@gs-press.com.au