Eastern Treatment Plant tertiary upgrade

​Construction is complete on a major upgrade of the Eastern Treatment Plant. The plant has been transformed into one of the most sophisticated large scale sewage treatment facilities in the world.

The upgrade involved building seven new structures over approximately six hectares of land within the existing Eastern Treatment Plant boundary. The new components include a tertiary supply pump station, ozone injection and ozone production buildings, biological media filters, UV system and two large chlorine contact basins.

What happened

In October 2006, the Victorian Government announced plans to upgrade the Eastern Treatment Plant to improve the quality of the treated effluent it produces.

A year of technology trials (completed in the first half of 2009) helped identify the best treatment process for upgrading the plant. Different treatment options were investigated in conjunction with world-class private sector partners.

The trials found that an advanced tertiary treatment process – Ozone and Biological Media Filtration coupled with ultraviolet and chlorine disinfection – would greatly improve the quality of treated effluent from the plant and address impacts in the vicinity of the discharge point.

In January 2010, EPA Victoria approved Melbourne Water’s application to upgrade the Eastern Treatment Plant. This followed a rigorous scientific assessment of the submission and a public consultation period that gave stakeholders and the general public the opportunity to comment on the planned upgrade.

We teamed up with Baulderstone, UGL Infrastructure, Black & Veatch and KBR to form the Eastern Tertiary Alliance to deliver the upgrade.

Why this project was important

The main benefits of the upgrade are:

  • reduced impact on marine environment at Boags Rocks, where treated water is discharged
  • more options to use treated water for non-drinking purposes (recycled water)
  • improved recycled water quality (Class A).

Specific improvements to water discharged into the marine environment will include:

  • eliminating litter
  • reducing solids, oil and grease
  • improved disinfection
  • reducing colour, odour, foam and ammonia
  • reducing the volume of water discharged to the marine environment.

Did you know?

40% of Melbourne's sewage is processed at the ETP, serving about 1.5 million people in Melbourne's south-east and eastern suburbs.


Key facts

  • Start: Mid 2010
  • Finish: December 2012
  • Cost: $418M

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