$90 million recycled water upgrade for Gold Coast
A significant milestone has been achieved on the City of Gold Coast’s (the City) Stage 1 Long Term Recycled Water Release Plan with the completion of a major upgrade of the City’s recycled water release system.
A major upgrade of the City’s recycled water release system at the Southport Seaway, including two of the longest marine pipeline crossings of their type in Australia, has been undertaken to allow for continuing Gold Coast growth.
With a project value of $90 million, upgrading this important infrastructure will increase the capacity of the existing network, which was first built 30 years ago.
Specifically, the project comprised:
- recycled water pump station upgrades at the Coombabah Sewage Treatment Plant and the Benowa e-Pump facility
- upgraded release points at the Seaway to allow for more efficient release
- new pipelines across the Nerang River and Broadwater to allow for increased volume of excess recycled water to be released at the Seaway
- upgraded pipelines on South Stradbroke Island.
A key element in of the project was the installation of 1.2 m diameter and 900m long polyethylene (PE) recycled water pipeline under the Nerang River from Southport to Main Beach, installed by Horizontal Directional Drilling (HDD).
In order to minimise the potential impact on the community and environment from stringing pipework for a large drill in a high traffic area of the city, the Project Team investigated alternative methodologies. The chosen approach was to weld 900 metres of pipe in 12 metre sections at Moondarewa Spit, just north of Sea World, and then float it down the Broadwater before pulling it into its final position in a pre-drilled bore under the Nerang River.
Logistics and solution planning for this particular part of the project took more than six months. Delivery partners included the principal contractor, John Holland, their partners Dunstans Construction Group, Marine Civil Contractors, Gem Industrial Services, the local community, Maritime Safety Queensland, Gold Coast Harbourmaster, Gold Coast Waterways Authority and the Queensland Water Police.
The final installation of the pipeline was completed over 48 hours of continuous works, with no safety or environmental issues. This is testament to the meticulous planning and execution undertaken ahead of this complex task.
Authors: Christian Truscott and Kate Paxman