Amiblu Supports Critical Sewer Upgrade Beneath Melbourne’s Yarra River

Country

Australia

City

Melbourne

Timeline

2023-2025

Application

Sewer

Total Length

1300 m

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One of Melbourne’s most ambitious infrastructure upgrades is making steady progress beneath the city’s iconic Yarra River. The Hobsons Bay Main Sewer Upgrade – a cornerstone in Melbourne Water’s long-term strategy to modernize aging wastewater infrastructure – is a highly complex, multi-year project designed to ensure the city’s growing population is supported by a reliable and resilient sewer network.

Originally constructed in the 1960s, the Hobsons Bay Main Sewer is responsible for transporting nearly 30% of Melbourne’s wastewater to the Western Treatment Plant. With the existing pipework nearing the end of its service life, a comprehensive rehabilitation is needed – without disrupting day-to-day operations.

Duplication and Innovation Beneath the Surface

The solution: a duplicate sewer pipeline stretching beneath the Yarra River between Westgate Park in Port Melbourne and Scienceworks in Spotswood. This newly constructed pipe will temporarily divert flow from the existing line, allowing essential rehabilitation works to be carried out safely and efficiently.

Amiblu was selected as a key supplier on this technically demanding project, providing a combination of Flowtite relining pipes DN2000 and Flowtite jacking pipes DN1700, totaling nearly 1.3 km of trenchless pipeline. With GRP’s renowned corrosion resistance, high stiffness, and lightweight structure, the material was perfectly suited to Melbourne Water’s requirements for durability and installation precision in a challenging urban environment.

Tunnelling Milestones with Precision

In November 2023, tunnel boring machine “Lucey” completed a 670-meter underground journey, marking a major milestone in the tunneling phase of the project. This microtunneling section required precise navigation beneath the Yarra River, without disturbing surface activity or compromising the sensitive river ecosystem.

In addition to tunneling, a range of essential tasks has already been successfully completed: tunnel grouting, sewer connection interfaces, spoil management, and long-term rehabilitation of legacy infrastructure.

What’s Next: A Tailor-Made Relining Solution

The next chapter of the project kicks off in 2025 with the rehabilitation of the original brick sewer, spanning 627 meters. Based on extensive inspections, this section requires relining to extend its structural integrity. Amiblu has already delivered a custom-engineered GRP relining solution, developed specifically to match the project’s unique hydraulic and geotechnical demands.

Smart Infrastructure in Action

Delivering such a project beneath a major urban waterway with zero surface disruption and full environmental compliance is no small feat. It requires cutting-edge engineering, stringent environmental management, and flawless coordination.

While the full system isn’t operational yet, the success of the tunneling stage and the planning for the next phase place this project firmly on track. Once completed, the upgraded sewer will offer increased capacity, longer service life, and greater environmental resilience – all crucial for a rapidly growing Melbourne.