Toukley desalination plant planned for 2039

Mangrove Creek Dam

The community has 28 days to comment on a draft Central Coast Water Security Plan which will determine the region’s water supply through to 2051.

Highlights of the draft plan include a purified recycled water scheme at Wyong South, a major desalination plant at Toukley and upgrades to three main bore fields at Ourimbah, Mangrove Creek and Woy Woy.

The plan also entails the delay of major new infrastructure development for over a decade.

Council’s Director of Water and Sewer, Jamie Loader, said the last plan was written in 2007 and numerous things had changed since then.

“We now have an improved understanding of rainfall and stream flow trends, there have been advances in technology and changes in our regulatory environment as well as updated population and water demand forecasts,” he said.

“All of this means that it is now time to update this plan.

“The vision is to provide a resilient and sustainable water future that promotes regional health, prosperity and is supported by the community.

“We took an all options on the table approach to ensure the most effective solutions could be identified.

“Short, medium and long-term actions will ensure we can secure our water supply and manage any risks associated with future droughts.

“It also an opportunity to update Council’s current drought management plan, so we know when we need to trigger what we call our emergency enduring supply pathway, which just means that during an intense and prolonged drought we can still supply a suitable ongoing source of water.”

Loader said the draft plan had been a work in progress since 2018 when Council partnered with Hunter Water Corporation to assess potential water options that might benefit both parties.

He said development of the plan included extensive technical assessment involving engineers, economists, academics and ecologists as well as a year of meaningful conversations by various methods with the community, including Aboriginal communities.

Council collaborated with the regulator, Department of Planning, Industry and Environment, and Hunter Water.

“We undertook risk and uncertainty assessments, which considered delivery and operation of each of the options, and within the overall supply and demand balance,” Loader said.

He said the consultation showed one thing clearly.

“The community values the reliability of climate-independent supplies – they want a water supply that doesn’t just rely on rain, and they want a water supply that is sensitive to the environment and cost effective,” Loader said.

“The community also showed support for the earlier levels of water restrictions and a desire for the strengthening of water wise rules.

There are three main pillars to the plan – the first to conserve and use water efficiently.

“Secondly, we will make the most of what we’ve got and maximise the potential of our existing water supplies, so we are able to delay constructing new supplies of water until further down the track,” Loader said.

“This involves a number of administrative and regulatory actions as well as upgrades and refurbishment of under-utilised infrastructure.

“The first two pillars will buy us time and defer large expenditure but cannot sustain the Coast’s water needs forever.

“The final pillar is all about addressing the uncertainty of the future.

“While we have run simulations and developed models to create our demand forecasts, the truth of the matter is simple – we don’t have a crystal ball to tell us exactly what is going to happen – we could experience a long and severe drought in the next 10 years and no one can predict this,” he said.

“Because of this, we will develop new supplies of water, such as desalination and purified recycled water that don’t rely on rainfall, for an adaptive future.

“While these items won’t be delivered until they are needed, we need to plan for them now so we can respond appropriately in the future.”

The plan allows the Central Coast to be adaptive to future uncertainties in population and climate.

“We intend to develop our future options through the planning phase now so that we are ready to deliver those in a timely manner whenever they are needed in future.

“We aim to provide flexibility in their scale and timing wo we can respond effectively to future risks and opportunities.

“Higher than expected demand or the impacts of climate change won’t change what we need to do, only when we need to do it and that plan has been developed to be efficient to get the most our of what we already have before investing in new supplies.

“We aim to have investigated and commissioned upgrades to our three main bore fields at Ourimbah, Mangrove Creek and Woy Woy by 2035.

“We aim to have upgraded and increased utilisation of our existing recycled water schemes by 2038.

“We are planning for the delivery of a purified recycled water scheme at Wyong South waste water treatment plant by 2039.”

Construction of a desalination plant in Toukley waste water treatment plant is another long term measure.

The draft plan is open for public comment until September 28, online at yourvoiceourcoast.com and a further report will go to a Council meeting before the plan is submitted to the Department of Planning, Industry and Environment for approval.

Jackie Pearson