Woodman Point Wastewater Treatment Plant upgrade (video transcript)

This animated video explains the upgrade plans for the Woodman Point Wastewater Treatment Plant, to make sure the plant continues to support the growing population in the catchment area.

Woodman Point Wastewater Treatment Plant is the largest wastewater treatment plant in Western Australia. It treats wastewater for a population of more than half a million people living south of the Swan River in the Perth metropolitan area.

The plant currently treats some 140 million litres of wastewater every day. 

To make sure the plant continues to support the growing population in the catchment area, an upgrade is needed.

Upgrade overview

The Woodman Point Wastewater Treatment Plant upgrade will increase the plant’s treatment capacity to 180 million litres a day. To allow the plant to remain operational during the expansion works, the upgrade will take place in 3 phases.

Upgrade – Phase 1

Phase 1 will see the construction of all structures, plant and equipment necessary for the upgrade works, with the exclusion of the Sequencing Batch Reactor conversion.

This phase will include the construction of:

  • a new grit removal facility
  • a new flow distribution channel and expansion of the existing odour collection and treatment system to accommodate 4 new primary sedimentation tanks, and
  • 8 new Secondary Sedimentation Tanks – while the overall upgrade only requires the construction of 6 new secondary sedimentation tanks, an additional 2 are required to ensure the plant maintains treatment levels during the retrofit of the sequencing batch reactor. Four secondary sedimentation tanks will be used as high-rate aeration tanks, while the other 4 will be used as secondary sedimentation tanks.

Following the completion of Phase 1 construction, the new assets will be commissioned as a temporary 150 million litre a day plant allowing for the sequencing batch reactor to be taken offline for conversion.

Upgrade – Phase 2

Phase 2 of the project will see the sequencing batch reactor converted to a permanent continuous aeration facility.

This includes the construction of:

  • baffle walls 
  • mixed liquor return duct and mixed liquor outlet weir structures within each of the 4 reactor basins
  • the installation of 3 submersible mixers
  • 5 submersible mixed liquor return pumps and
  • 1 submersible drain pump in each reactor basin.

Upgrade – Phase 3

Phase 3 will see the commissioning of all structures, plant and equipment to achieve the final plant configuration to treat 180 million litres a day.

This will involve diversion of flow to its final configuration into the converted sequence batch reactor, and then after treatment in this permanent continuous aeration facility, through to the 6 operational secondary sedimentation tanks.

The 2 additional secondary sedimentation tanks will aid with future expansions.

Once the effluent has been clarified through the secondary sedimentation tanks, the final effluent will be discharged into the Sepia Depression Ocean Outlet Line for disposal.

Once complete, the upgraded Woodman Point Wastewater Treatment Plant will have an operating capacity of 180 million litres and will be able to accommodate a population of more than 900,000. This vital upgrade will ensure that we can continue to provide essential wastewater treatment services for the growing population of Perth.