Located 75 km from Melbourne, the HMAS Cerberus site occupies more than 15 km2 near Crib Point on Hanns Inlet, Western Port Bay in Victoria, with approximately 980 uniformed, defence, civilian and contracted staff working at the base.
There are also approximately 6,000 training places per year across 300 courses, which range in duration from one week to 12 months – resulting in an average of 1,100 trainees at any one time throughout the year.
Work on the new sewer mains commenced in December 2018 and job planning with Land Engineering and other contractors onsite became vital due to the purer size of the construction site. Tunnelling works were spread out over a 15-month period and the operation’s last drill shot was completed in March 2020.
Project specifications
This project consisted of approximately 30 tunnel boring machine (TBM) setups and 20 launch shafts ranging from 1.5-9 m deep. The total distance of drilling accumulated over the 15 months was 1.6 km.
Various pipe sizes were installed, including 150 mm, 225 mm and 300 mm Iplex restrain pipe, while there was also one 50 m drive that involved pipe jacking 427 mm of Hobas GRP pipe. L&D Microtunnelling says the drill provided an opportunity to design and construct a new drill head to not only suit the pipe used but the ground conditions as well.
“We encountered mostly friendly ground conditions throughout the project. Most drives were through sandy clay, but in some areas, it was a lot more challenging as we faced high plasticity clays and unstable sandy clays,” says the company.
“Groundwater was also a challenge in most of the deeper shafts as we were drilling very close to and even in a few circumstances under the water table.”
The company says it was very proud of its crew’s efforts to successfully complete its biggest project to date.
Built on experience
L&D Micro Tunnelling was established in 2015 by lifelong friends, Luke Lewis and Christopher Dean, who first began working together in 2011 as a site foreman and microtunnelling operation supervisor respectively. Mr Lewis is a qualified plumber and drainer while Mr Dean is a qualified fitter and machinist, bringing their total combined experience in the sewer and water industry to 20 years.
Both men understand the need for precision, pride themselves on building client relationships and thrive to always deliver an economic, reliable service to companies across Australia. Over the past five years, L&D Micro Tunnelling has completed 50 projects and drilled more than 11 km – with many more projects and kilometres to come.
This article was featured in the December 2020 edition of Trenchless Australasia.
For more information visit the L&D Microtunnelling website.
If you have news you would like featured in Trenchless Australasia contact Journalist Sophie Venz at svenz@gs-press.com.au