Location: Melbourne, Victoria
Overview: The Sugarloaf Pipeline links Melbourne to the Sugarloaf reservoir and will deliver 75 billion tonnes of water each year. The planning, design and construction of the project fell to the Sugarloaf Pipeline Alliance incorporating John Holland, SKM and GHD. The complex project was delivered through some of Australia's most sensitive ecosystems, and required significant community relations and consultation.
Description: The Sugarloaf Pipeline is a 70 kilometre pipeline linking the Goulburn River in Melbourne’s north-east to the Melbourne Water distribution network via the Sugarloaf reservoir in the Yarra Ranges and will deliver 75 billion litres of water to Melbourne each year.
The planning, design and construction of the Sugarloaf Pipeline project was undertaken by the Sugarloaf Pipeline Alliance, an alliance between Melbourne Water with John Holland, SKM and GHD.
The Alliance was also responsible for environmental assessments, community and landowner consultation, project management, archaeological investigation and regional benefit offsets.
The Sugarloaf Pipeline was predominately constructed using trenched excavation. However, an 830 metre section within the Toolangi Forest, where steep crossfall precluded trenching, was constructed using tunnelling methods.
The construction of the tunnels utilised pipe jacking technology. The diameter of the tunnel excavation was 2.47 metres in order to accommodate a 2.0 internal diameter standard jacking pipe. A steel pipe of 1.6 metre outer diameter was then installed within the jacking pipe and grouted in.
Tunnel excavation was completed in 10 working weeks without incident and is believed to be the longest single drive for a pipejack of this size in Australia. The alignment also included a 680 metre long curve with a radius of 825 metres.
John Holland's involvement required input from a number of its business units, including the Water & Enviro, Tunnelling, Energy and Southern Region businesses.
As part of the project, Melbourne Water funded a $5 million grants program called the Regional Benefits Grants Program, for community and environmental groups in the affected region.