Maribyrnong River Main to North Western Sewer Connection project

In Melbourne, a safe, clean and healthy environment is essential to our way of life. Our city is always changing with more people wanting to call Melbourne home. Without improvements and innovations, our sewerage network would reach capacity and our waste would impact on the health of our environment.

That’s why we’re building a new 1.2 kilometre sewer in the suburb of Maidstone to accommodate Melbourne’s growing population. Keeping our city healthy is essential to our way of life today, tomorrow and for generations to come.

Why this project is important

This sewer is one of the main sewers in Melbourne Water’s sewerage network. The new sewer will:

• Provide a secure and reliable sewerage service for more than 86,000 people over the next 100 years
• Transport sewage to the Western Treatment Plant, located in Werribee
• Protect the Maribyrnong River by containing sewage flows.

What are we doing?

The new sewer will be built over stages, using a combination of construction techniques.

We have completed the first stage between Hampstead Road and Medway Golf Course in Maidstone.

This work included:

• Tunnel boring machine (TBM) – excavation of launch shaft to install TBM for 800 metres of sewer to be fed underground at approximately 30-40 metres deep
• Open cut trenching – the remaining section of the sewer will be constructed underground at a depth of 2-4 metres

Stage 2 to connect the new pipeline to the Maribyrnong Main Sewer is currently on hold.
We are reviewing the proposed pipe-bridge design and an alternative tunnel option to carry the new sewer across the Maribyrnong River using the new flood modelling, to ensure there are no adverse impacts to the flood plain.

More information will be available in October 2025.

Timeline