The Central Coast region of New South Wales, Australia, is making significant strides to safeguard its drinking water supply, with the region’s largest water infrastructure upgrade in a decade progressing alongside future drought-resilience planning.
Central Coast Council, in partnership with Abergeldie Complex Infrastructure and the NSW Government, is delivering the AUD 82.5 million Mardi Water Treatment Plant upgrade. Supported by an AUD 6.85 million contribution from the NSW Government’s Restart NSW Safe and Secure Water Program along with over AUD 75 million from Central Coast Council, the project is on track for completion by July 2026.
Mardi Water Treatment Plant currently supplies about half of the Central Coast’s drinking water and will, once upgraded, be capable of treating the equivalent of 64 Olympic-sized swimming pools each day—enough for more than 210,000 homes and businesses across the Central Coast region and the lower Hunter Valley.
Key works include a new Dissolved Air Flotation (DAF) clarifier and flocculation tanks to improve performance in poor raw water conditions, upgraded chemical dosing facilities, and refurbished outlet and storage systems. These enhancements will ensure the plant can reliably produce up to 160 million litres of water per day under all projected raw water quality conditions, improving resilience against algal blooms and storm impacts, and maintaining water quality for the community. Four major shutdowns have been completed without impacting customers, with a fifth scheduled for March–April 2026.
While these upgrades will strengthen the existing network, Council is also preparing for worst-case drought scenarios through the proposed Toukley Desalination Water Treatment Plant. The facility would be built beside the existing Toukley Wastewater Treatment Plant, but only constructed if needed during a future drought. It would provide up to 30 million litres of drinking water per day, independent of rainfall.
Council Director of Water and Sewer, Jamie Loader, said: “Running out of water is not an option, if a drought hits and dam levels fall, we won’t have time to start from scratch. We need to have approvals in place so we can act quickly to protect the community’s water supply.”
Mr Loader said the project had “already evolved in response to community feedback” and added: “We’ve listened to the community and made significant improvements since the original desalination proposal. This includes moving the ocean intake further offshore to reduce impacts on local beaches. Now, we’re asking nearby residents to help us identify what matters most to them when choosing the best location for the pumping station.”
Together, the Mardi upgrade and desalination planning form part of the Central Coast Water Security Plan, designed to ensure safe, high-quality drinking water for a growing population, regardless of weather conditions.
