The desalination process separates dissolved salts and other minerals from seawater to produce drinking water. It uses an advanced technology called reverse osmosis to remove the salt. The water produced is called permeate and is similar to distilled water. Permeate is then re-mineralised so it can be blended with other treated water or directly distributed to homes, businesses and industries in the region. Unlike the majority of drinking water produced in South East Queensland, desalination does not rely on rainfall and is a critical, climate-resilient water source during drought and flood. 

Water is a precious resource. Currently, the majority of water provided to  South East Queenslanders is dependent on rain. We live in a climate of extremes, and with a growing population and the known impacts of climate change, desalination offers an alternative source of drinking water including in times of flood and drought. 

Of course! Desalinated water undergoes a comprehensive multi-staged treatment process to meet strict public health regulation standards and the Australian Drinking Water Guidelines 2011. It is regularly tested to ensure it is clean and safe. You can find out more about the treatment process here: https://youtu.be/m90NCiRwx28?si=eQUSC6oe_I_o5TSt 

The Gold Coast Desalination Plant (GCDP) is an important climate-independent water source within the SEQ Water Grid. Unlike conventional water treatment plants, that treat water from dams, the GCDP can supplement supply into the SEQ Water Grid without relying on rainfall. The GCDP has been in operation since its introduction to the SEQ Water Grid in 2009, and its operation is ramped up and down based on demand and network requirements. The GCDP can operate during periods of drought, and when conventional water treatment plants are required to go offline due to maintenance, or flood events when water quality may become impacted.  

In 2022-23, the Gold Coast Desalination Plant produced 7,310 ML of treated bulk water to support the operation of the SEQ Water Grid, including in response to the 2022 flood events when raw water quality issues reduced production at conventional water treatment plants. In the two years prior to this, it was also used extensively as a drought response measure. 

Seawater is filtered through an inlet structure on the seabed. Desalination plants implement measures like advanced screens, water velocity control, and strategic intake locations to minimise their impact on marine life. Fish and marine animals are not able to be drawn in, as the flow in to the inlet is slower than the natural current. A protective grill is also installed on the pipe so larger fish and marine life are not able to swim into the pipe.  

For the Gold Coast Desalination Plant, Seqwater has a long-term independent marine monitoring program in place, which shows that the plant operates in compliance with licence conditions developed to prevent environmental impacts. 

Results show small plants and animal organisms are thriving on and around the underwater infrastructure. Footage shows that the sea water intake is providing a habitat for a diverse variety of marine organisms, effectively creating an artificial reef. 

Interestingly, these measures often create thriving habitats for diverse marine organisms around intake structures. 

The seawater not converted into drinking water, called brine, is returned to the ocean through an underground pipe. This process is managed in a way that minimises environmental impact. Techniques like dilution, dispersion, and use of specialised diffusers ensure controlled discharge, reducing the impact on marine ecosystems. Real-time monitoring of the quality of the brine discharged back into the ocean includes measurement of pH, chlorine, dissolved oxygen, temperature, turbidity and salinity. 

Components of a desalination plant include an intake structure located offshore, an intake pump station located at the desalination plant and a pipeline that connects the two.  

The pipeline is underground to minimise impacts. The pipeline outlet in the ocean is a suitable distance away from the beach to not impact on beach goers and water recreation.  

In the case of the GCDP, the intake structure is located approximately two kilometres from shore. 

The design of a desalination plant typically includes soundproofing materials, noise barriers, and quieter equipment to limit noise disturbances once in operation, maintaining a peaceful environment for the surrounding community. 

In line with the Queensland Government’s Energy & Jobs Plan, Seqwater is committed to a more sustainable future. 

Seqwater’s approach to Sustainability and Environment Social & Governance (ESG) is targeted towards potential opportunities to transition asset management and operations to a more sustainable future. 

Over the next five years, Seqwater’s investments in projects and initiatives will incorporate consideration of how Seqwater sources and consumes energy within its operations, as well as across its energy-related value chain.