Is our drinking water supply threatened by Dunoon Dam?

Most people don’t know that the proposal for Dunoon Dam (the Dam) has never been part of Rous County Council’s (RCC) 40-year, adopted, strategic plan to increase water supply, resilience and security, known as Future Water Plan 2060 (the Plan).

Reasons to include the Dam were not convincing. The Dam was ‘on the table’ in 2014 along with demand management, increasing groundwater sources, recycling, and desalination.

There was an attempt to put it on the table again during the 2021 revision of the Plan, but it was again rejected.

Why was the Dam rejected twice?

It’s all about climate change. Strategic future planning for water security in a time of rapid climate change is mandated by the NSW government through the Department of Planning and Environment (DPE).

Planning is to be evidence based and the DPE does its own intensive investigations. In its latest Far North Coast Regional Strategy from July it did not find sufficient evidence to justify the Dam.

The DPE did find evidence to be wary of dams because they flood, causing damage, and they dry up, especially with increased evaporation, more heat, and longer droughts. Therefore, rainfall dependency must be significantly reduced for future water security and come from a range of sources for resilience.

Dams are susceptible to periodic microbial infestation rendering them unsuitable for drinking water, as is currently the case for Ballina Shire’s Emigrant Dam.

The Dunoon Dam was not selected after careful deliberation and exemplary consultation in
2014. The Dunoon Dam was set aside because preliminary studies (Cultural/Heritage 2011 and Terrestrial Ecology 2013) reported serious destruction to both. The DPE, in its own 2023 strategy recently classified the damage as ‘extreme’.

The Dam was not selected as it could not contribute enough new water for the estimated population growth and climate changes as well as being too expensive.

The 2021 revised plan came to the same conclusions and strongly emphasised decreasing rainfall dependency as climate change risks became better understood.

In 2021 there was a stronger emphasis on recycled water as it is substantially always there – it needs very little rain. Desalination is an unlimited supply and totally independent of rainfall, and is becoming cheaper as new technologies emerge.

Since February 2022 there have been two poor planning moves that put water security at risk.

No comprehensive brief

At the first meeting of a newly-elected RCC in February 2022 they resolved 6-3 to put the Dunoon Dam back into consideration.

There was no brief, and still isn’t. There was no explanation of why a future plan was required; no serious consideration of climate change; no mention of the critical role of rainfall – dams are totally rainfall-dependent.

It was a serious omission that has allowed inadequately informed councillors to include investigating the option of the Dunoon Dam based upon their political and personal preferences, to misinterpret evidence, and to ignore the studies that RCC had already done. The thought was that new studies would have preferred outcomes.

Focus on the Dam

This unprofessional process continues and RCC recently announced that it had a new Future Water Plan to secure our bulk future water supply until 2060.

RCC General Manager, Phillip Rudd (Letter, 27 December, 2023) named new long-term sources of water as recycled, desalination, surface water (Dunoon Dam) and ground water. He claims that every option should be on the table, and long-term supply options are ‘at the preliminary stage’ because they are new.

These claims are dangerous because none of the options are new; everything was on the table for possible selection at the beginning of consideration of a Future Water Plan 2060. All selected options already have substantial, comprehensive, science based, preliminary studies that have informed, and can inform, existing choices. The existing studies do not differentiate between short and long term – that is a RCC invention for political purposes.

The declaration of ‘preliminary’ for everything allows RCC to ignore existing evidence, ignore inconvenient expert opinion, take its time to decide what to do about other parts of the plan that it has never been interested in, whilst it gets on with its only real preferred option, the Dam. Ground water was already progressing because of earlier fears of drinking water running short in 2024.

The advertised tender for the new (third) preliminary investigation into Heritage/ Cultural and Ecology of the Dam site has just closed. Rudd claims in his letter it is ‘only to inform decision making about whether to retain or remove this option’. So, if RCC doesn’t like it, they can follow usual practice – ignore it and/or do a fourth one.

Political scare campaigns

The RCC website as late September 2023 acknowledges that there are previous studies on purified recycled water and desalination. At its December 2022 meeting RCC cancelled the pilot recycled water project in Caniaba’s Perradenya Estate (a new housing development).

This was due to the scaremongering ‘toilet to tap’ political campaign against recycled purified water in 2021 from Ballina Councillors Sharon Cadwallader and Rod Bruem.

The 2020 CWT and the Ganden reports, embedded in Hydrosphere Consulting; Rous Future Water Project 2060 are recent, comprehensive, science-based, detailed – with all pros and cons of each water option, possible sites, and construction suggestions. Development of future options can be made from these papers.

The RCC needs to improve its credibility ASAP with: An independent comprehensive brief, mandated to be continually updated; a realistic timeline for actual recycling and desalination plans based on choices and in existing scientific studies; extensive, intensive, and continuous community education and involvement; along with the public exhibition of the brief, the timeline, and whatever is the Plan now.