$600 million in sewage upgrades to cater for growing population

Coombabah Sewage Treatment Plant upgrades

A $160 million upgrade to the Coombabah Sewage Treatment Plant is in the final stages of commissioning, increasing its capacity by 30% and servicing an extra 140,000 people.

Mayor Tom Tate visited the plant, one of three that were recently upgraded to service our growing population.

“The $160 million upgrades ensure the Coombabah Sewage Treatment Plant can cater for the northern and central part of the city for many years, and now services more than 480,000 people,” Mayor Tom Tate said.

“This upgrade is part of a $600 million planned investment in upgrading sewage treatment plants to increase capacity and reduce the environmental impact.

“This is vital infrastructure as we plan for our future population which we know will grow significantly in coming years, particularly in the north.”

He said the project also included $6 million to improve the plant’s odour control unit.

The planned upgrades include:

  • Coombabah Sewage Treatment Plant – $70M – will become the centralised facility to manage and process biosolids from Coombabah, Pimpama, and Merrimac. This facility will reduce the volume and improve dryness of the product. Contract expected to be awarded in late 2025.
  • Coombabah Sewage Treatment Plant – $100M – new infrastructure includes primary sedimentation tanks for process downstream of existing preliminary treatment facility, pumping facility and other process intensification technologies. Contract expected to be awarded in 2028.
  • Pimpama Sewage Treatment Plant – $140M – doubling capacity and adding primary treatment facility (screenings and grit removal), bioreactor, two clarifiers and modifications to existing tertiary treatment facility. Contract expected to be awarded in mid-2024.
  • Merrimac Sewage Treatment Plant – $140M – can cater for 90,000 additional people. Contract expected to be awarded in late-2024.
  • Elanora Sewage Treatment Plant – $77M – increasing capacity by about 25,000 which will ensure serviceability for the next 20 years. Contract expected to be awarded in 2024.

In May, a cogeneration facility was completed at the Coombabah facility which provides about 300KW of power to the site.

This power is created using methane gas generated from the sewage treatment process to produce electricity which then supplies energy to the plant’s equipment thereby reducing Energex costs and minimises emissions and greenhouse gases.

/Public Release. View in full here.