Coolum Demonstration Wetlands Project

Project summary

Wetlands are one of nature’s ways of cleaning water, filtering and trapping sediment and recycling nutrients. Unitywater has identified that using wetlands in conjunction with existing sewage treatment processes may provide a cost effective, environmentally sustainable augmentation solution.

At the Coolum Sewage Treatment Plant (STP), Unitywater has planted trial wetlands to demonstrate their value.
The demonstration wetlands are being used to polish effluent from the existing treatment process, reducing impacts on the receiving waters. Increasing the standard of treatment provided will result in a healthier Maroochy River for the community. The trial wetlands also provide a habitat for native flora and fauna.

Information gathered on the performance of the demonstration wetland will be used to design low cost, environmentally sustainable treatment solutions for the future augmentation of the Coolum STP. This augmentation is required to increase the capacity of the treatment plant from 6 to 9 million litres a day, which will cater for anticipated growth in the region.

The demonstration wetland project has four phases:

1. Construction and commissioning (complete)
2. Establishment and monitoring period (complete)
3. Mature wetland monitoring period and performance assessment (starting September 2016 for 3 years)
4. Use of data to support the design of the treatment plant augmentation.

At the conclusion of the demonstration project, Unitywater plans to work in partnership with Sunshine Coast Regional Council to develop full scale wetlands that could rehabilitate up to 165,000 m2 of disused cane land beside the existing treatment plant.

The Coolum STP serves the catchments between North Marcoola and South Peregian and includes the suburbs of Coolum Beach, Mt Coolum, Yaroomba, Coolum Ridges and Peregian Springs.


Fast facts

Location Marsh Road, Coolum.
Completion dates

Construction of the demonstration wetlands was completed in August 2013. An establishment and maturation period followed to August 2015.
The performance of the wetland will be monitored continuously for a further three years to determine the configuration of the full scale wetland. The trial is due to finish in August 2019.


The demonstration wetland project will:

  • improve the level of treatment at the Coolum STP
  • assess wetland treatment performance
  • reduce the impact on the environment and improve the quality of water discharged to the Maroochy River
  • provide site specific data for the design of full scale wetlands for the future sewage treatment plant augmentation
  • facilitate the development of environmentally friendly, cost efficient treatment options.

Donnan (Qld) Pty Ltd

Funding $2.4M (wetlands only)


More information

If you have any questions or would like more information, please contact us.

 Coolum Demonstration Wetlands

  Coolum Demonstration Wetlands

 Coolum Demonstration Wetlands

 Coolum Demonstration Wetlands

    Did You Know
  • A garden hose can use 15 litres of water per minute. That's 150 litres of water in just 10 minutes!