9 October 2024

ALAN HAYES

 

THERE are three key issues in desalinating salt water - high energy use leading to carbon emissions, creation and disposal of toxic brine waste, and possible chemical contamination from plant operations. Yet the inherent problems of desalination seem to have escaped Council bureaucracy, who, for the past four years, and have been unaccountable for their actions, ignore the reasons why desalination was previously rejected by an elected council.

 

The draft Central Coast Water Security Plan is geared for overpopulation and a push for a desalination plant at Toukley and an outfall and intake in the Norah Head area.

 

Using short term and long term forecasts of rainfall, as noted in the NARClim Report (NSW and ACT Regional Climate project (page 12 and 13), it does not suggest less rainfall overall into the future or that we will be entering into a drought period. There will be, instead, dramatically more rain in thirty-years-time as the effects of climate change become apparent. It is this document that Central Coast Council has use for their modelling. So, why do they maintain the Central Coast will be drought effected?

 

It is negligent for Council to suggest that there will be less average rainfall overall to the year 2039 to justify moving forward with desalination.

 

So, why is Council opting for the construction of a desalination plant that will not come into operation by 2039? Why is it Council’s plan to begin construction on the desalination plant ‘ocean inlet’ in the next 2 to 5 years? And why will ratepayers be expected to ‘kick the can’, for what could likely be an extra $3600.00 on their annual rates bill, just to satisfy the whims of council bureaucracy?

 

Council staff argue that they already have approval, allegedly granted in 2006, to build a desalination plant – this is untrue. When the Central Coast was in severe drought at the time, the councillors' of the day investigated building desalination plants but the proposal was ultimately rejected because of the small amount of water that is produced against the enormous cost of running the plant – there was no approval to construct a desalination plant.

 

Council claim that the storage capacity of the three dams servicing the Central Coast Region fell during the bushfire drought (2017 to 2020, and highlights the climate dependence and vulnerability of the supply.

 

In January 2020 the total water storage on the Central Coast dropped to 50 percent but was quickly replenished by the Mardi-Mangrove pipeline, which quickly climbed to 75 percent by March 2021, with total water storage at 98 per cent by July 2022. The current total water storage is 89 per cent.

 

During the severe drought period in the early part of the new century, Mangrove Creek Dam still had sufficient water to provide for the Central Coast for several years, and that was when water levels dropped to around 43 percent.

 

Since the Mardi-Mangrove pipeline construction, to guarantee the future water security of the Central Coast, the Mangrove Dam has always stored high levels of water. The Mayor of the day Bob Graham was able to secure $80.3 million from the Commonwealth toward the cost of the pipeline's construction. The remaining $40 million was borne by ratepayers, which they are still paying for. There is no doubt that this worthy project has served the Coast very well and will continue to do so.

 

In 2023, Central Coast Council’s own records revealed that demand on water supply has decreased, despite a population growth of 50,000 people, which was attributed to improved water conservation, education and policy changes.

 

Council claims don’t stack up

 

The new Water Security Plan, according to Council, promotes desalination upon the need to counter forecasted climate change conditions, yet their own figures don’t stack up. It only stacks up if it’s assumed that their forecast of 52,000 new homes to be built in the next 30 years, and more than 120,000 new people in that short time, is correct and that we enter severe drought conditions. But this assumption contradicts the rainfall and climate conditions as outlined in the NARClim Report for the Central Coast region.

 

It is an overpopulation forecast, not climate, that the Council staff and State Government is relying upon to stretch all our resources of water, green space, waterways and forests, roads and services beyond sustainability.

 

A far less expensive option to guarantee water security into the future would be to raise the wall of Mangrove Creek Dam. Even without modifications to the dam wall, a recent engineers report has confirmed that Mangrove Dam can now increase its holding capacity.

 

Desalination is not only a cost to be borne by ratepayers – capital construction outlay and running and maintenance costs; it is the harmful environmental impact and, most important, the adverse impact on human health.

 

According to the Productivity Commission, Australia’s Urban Water Sector: Productivity Commission Inquiry Report, Australian Government, 2011, page XXIII, desalination should be a last resort because of its adverse impacts - high cost and environmental degradation – and only considered where water is scarce due to drought.

 

Desalination presents a grim future

 

Desalination plants are complex systems, with pre-treatment filters, high pressure pumps, energy recovery devices and chemical cleaning systems, and have high capital costs, significant maintenance requirements and shorter operating life than traditional water treatment plants. The saltier the water the more expensive it is to desalinate.

 

Because desalination requires a lot of energy, the plants are very expensive to maintain. Energy is reported to be the largest single expense for desalination plants, accounting for as much as half of the costs to make drinking water from the sea viable. According to a report from Pacific Institute, “Desalination plants on average use about 15,000 kilowatt- hours of power for every 4.5 million litres of fresh water that’s produced.” And these high energy requirements raise concerns about emissions.

 

The costs of desalination are not just monetary but environmental as well. Beyond the links to cost and climate problems, marine biologists warn that widespread desalinisation could take a heavy toll on ocean biodiversity; sea life can get sucked into desalination plants, inadvertently kill millions of plankton, fish eggs, fish larvae and other microbial organisms that constitute the base layer of the marine food chain. There is also concern of what happens to the separated salt, which is left over as a very concentrated brine. Pumping this super salty water back into the ocean can harm local aquatic life.

 

According to Jeffrey Graham of the Scripps Institute of Oceanography’s Centre for Marine Biotechnology and Biomedicine, the salty sludge leftover after desalinisation for every 4.5 litres of freshwater produced, another 4.5 litres of doubly concentrated salt water must be disposed of, which can quickly wreak havoc on marine ecosystems if dumped willy-nilly offshore.

 

“For some desalinisation operations,” says Graham, “it is thought that the disappearance of some organisms from discharge areas may be related to the salty outflow.”

 

A desalination plant on the Central Coast would cost, based on current figures, beyond $500 million to build - $300 million up on the original estimate three years ago, and cost annually at least $20 million permanently every year to operate, beyond the capital cost to build it - this will increase exponentially over time. The monetary costs of building the desalination plant begins with at least $3000 or more per household. A huge impost on the Region’s ratepayers.

 

The impact on human health

 

In 2018, scientists established a link between the consumption of desalinated water in Israel and a 6% higher risk of suffering from heart-related diseases and death by a heart attack.

 

The review found that “healthy” water in terms of electrolyte balance is as important as “pure” water in promoting public health. It considered that the growing use of desalination (demineralization) technologies in drinking water treatment, which often results in tap water with very low concentrations of sodium, potassium, magnesium and calcium Ingestion of such water, can lead to electrolyte abnormalities marked by hyponatremia, hypokalaemia, hypomagnesemia and hypocalcaemia. These abnormalities are among the most common and recognizable features in cancer patients.

 

The review also found that causal relationships between exposure to demineralized water and malignancies are poorly understood. It  highlights some of the epidemiological and in vivo evidence that link dysregulated electrolyte metabolism with carcinogenesis and the development of cancer hallmarks. It discussed how ingestion of demineralized water can have a procarcinogenic effect through mediating some of the critical pathways and processes in the cancer microenvironment such as angiogenesis, genomic instability, resistance to programmed cell death, sustained proliferative signalling, cell immortalization and tumorigenic inflammation.

 

An unnecessary financial burden

 

The Central Coast community should be concerned about Council’s rush into desalination. Council Director of Water and Sewer, Jamie Loader, said that this plan will ensure there is enough water on the Coast for all residents until 2051. The desalination plant would not be operational until 2039, which is at odds with the NARClim Report.

 

Mr Loader also claimed in an email in 2021 to the Grapevine that a representative sample of the Central Coast community was taken on a journey to learn about their water values and educate them on the different water supply and demand options being considered.

 

“Three phases of community consultation consisting of deliberative forums and in-depth phone interviews were conducted in December 2020, and February and April 2021,” Mr Loader said.

 

“It was during the third phase that Council presented the five water portfolios – or groups of options – to the community through these forums so we could learn what a representative sample of the Coast community’s support levels on each were.”

 

Investigations by the Grapevine have discovered that only 308 surveys were completed, 116 people participated in forums and 230 stakeholders were kept up to date - hardly representative of the Central Coast community and has no value upon which to make a decision that will impact on a population of around 327,000 people.

 

During the consultation process, however, members of the community raised concerns about how construction and operation of the project would be funded as a Council asset – the project was then presented as a capital expenditure cost of $200 million and running costs of $12 million. Yet, not surprisingly, Council have now said that the total cost of the project would be determined when construction was triggered – a sobering thought for ratepayers.

 

Far more disturbing is Council staff claims that the desalination plant could be funded through a combination of Federal and State Government grants – despite no guarantee or commitment that this will occur or funding having been evaluated. Then comes the kicker: funding through future Independent Pricing and Regulatory Tribunal (IPART) determinations – a government body pretending to be independent for the benefit of ratepayers.

 

So, why the urgency to go down a path of desalination, which has proven to be a plan of last resort?

 

And why the urgency to push through a project that was previously rejected by Wyong Council because it was unsustainable and before our elected Councillors have had the time to adequately assess and vote on the project?

 

In August 2022, when Mangrove Dam was at 100 per cent capacity, the first time ever, Council Administrator Rik Hart, on the same day, was on ABC Radio discussing the desalination plant. He assured Jilliby resident Mike Campbell, during the talk back program, that the desalination project “would never be built in our lifetime".

 

Desalination plants are costly to build, expensive to run and maintain, cause unacceptable destruction to the environment and will see water become very expensive!

 

When Wyong Council looked at desalination 18 years ago, they sank the idea where it belongs, in the rubbish basket.

 

What has changed? Absolutely nothing!

Name (First & Last):

Email:

Submitting Form...

The server encountered an error.

Subscription received.

SUBSCRIBE