Transport for NSW acknowledges that, as with any major infrastructure project, the construction of the Parramatta Light Rail will involve some disruption.
Why was micro tunnelling used in the Parramatta CBD?
Micro tunnelling was used to build drainage and stormwater capacity underneath Parramatta’s Church Street, including ‘Eat Street’. The use of micro-tunnelling machines helped to minimise construction impacts in comparison to traditional pipeline construction at street level.
This reduced the chances of impacting other pipes, electrical wires and utilities, and minimised noise, dust and vibration on Church Street. While micro-tunnelling work was underway, businesses and the community continued to access public spaces such as Centenary Square.
What is micro tunnelling?
Micro tunnelling is an innovative method of construction used to create a tunnel under the ground. The machine is remotely operated and similar to a tunnel-boring machine but smaller in diameter (approx. 1.5 metres).
How will micro tunnelling work for the light rail?
A micro-tunnelling machine dug six metres underneath Church Street, from Centenary Square to Lennox Bridge. Launched from a pit in Centenary Square, pipes of concrete were pushed behind the machine to cut the tunnel, and continued to a retrieval pit at Lennox Bridge.
A second, smaller micro-tunnel machine drilled across Centenary Square to a second pit outside Parramatta Town Hall, connecting to an existing pipe to extend stormwater capacity.
In total, nearly 600 metres of micro tunnelling was undertaken on the Parramatta Light Rail project.
What were the benefits of micro tunnelling?
- Minimised the impact of construction through built-up environments like Parramatta’s Church Street.
- Reduced road and footpath excavations, as it is limited to a launch and retrieval pit.
- Smaller construction sites compared to trenching Church Street at street level then laying down a new pipe.
- Quicker and safer compared to traditional excavation methods.
- Work could be undertaken 24 hours a day with minimal impact on the community.
Micro tunnelling is a discreet construction approach that will be used to create drainage underneath Parramatta’s Church Street in the CBD.
'Elizabeth' micro-tunnelling machine tracker