In 2018, the Department of Environment, Science and Innovation (DESI) approved Unitywater’s application to incorporate the riverbank stabilisation works as a nutrient offset.

The nutrient offset achieved from these works will offset forecast increasing nutrient discharges from the Burpengary East Sewage Treatment Plant (STP) due to population growth and development in the STP catchment.

The business case for the proposed nutrient offset works identified that establishment of the works in the lower Caboolture River is the most efficient and beneficial approach to management of nutrients.

Further to this, the business case also identified that the establishment of nutrient offset works prior to upgrade of the Burpengary East STP is a prudent investment, which will reduce the cost of treatment services by deferring investment in the performance improvement works at the STP.

 

The population growth in the Caboolture/Burpengary area will place a lot of extra pressure on both the environment and on our sewage infrastructure in the future. This project will offset the equivalent load of an additional 5500 people on our Burpengary East Sewerage Treatment Plant (STP).

Nutrient offsetting is a cost-effective option that provides flexibility in upgrading STPs. It enables Unitywater to make a positive contribution to our environment and community spaces, by actively working to improve the health of local waterways.

Unitywater has carried out other nutrient offsetting projects at its Yandina Creek Wetland and in the Upper Caboolture River at Bellmere.

 

Around 300 logs and rootballs will be used to protect the newly revegetated banks from erosion, many of which have been salvaged from clearing works along the Bruce Highway upgrade sites.

Pre-construction activities on the riverbank stabilisation will include tidal monitoring and procurement of materials and vegetation stock. Following that there will be site establishment; bulk earthworks; construction of log bank protection elements; revegetation; and establishment and maintenance of the works post-completion of construction.

 

Overview of riverbank restoration sites

Project timeline

Nov 19 - Sept 22
Design, feasibility and approvals
Mar 23 - Jan 25
Delivery (construction and establishment)
Jan 25 - Nov 25
Operationalise and handover
Nov 2025
Close and monitoring commences