The New South Wales government has scrapped one of the largest and most expensive water security projects in the state and the decision has drawn condemnation from Lachlan Shire.

In 2019, a Government proposal was approved to raise the Wyangala Dam wall by ten metres and in turn, increase storage capacity by 53 per cent. Wyangala Dam, near Cowra, was named as part of a jointly funded $1 billion plan to deliver new or upgraded dams in NSW.

At the time, the government said the project aimed to secure water supply and provide flood mitigation in the Lachlan Valley. Construction was expected to take four years.

Water Minister, Rose Jackson blamed cost blowouts and environmental issues for abandoning the plans that have already cost $74 million in pre-planning.

"Robust investigations show that while raising the wall by 10 metres is technically feasible, it could cause substantial and irreversible environmental impacts," Ms Jackson said.

"Hydrological modelling also found raising the wall, with a five-metre flood mitigation zone, was also likely to have devastating impacts on the internationally significant downstream environment, resulting in excessive biodiversity offset costs."

This reasoning "doesn't hold water" for Lachlan LGA with Mayor of Lachlan Shire Council, Cr John Medcalf joining other Mayors and communities of Central NSW to express his disappointment in the announcement by the NSW State Government that the project will not proceed.

“The Lachlan Valley has the most insecure water supply of any catchment in NSW. At the same time, flooding in the Lachlan Valley has been extreme over the past decade," Mr Medcalf said.

"Climatologists are predicting more severe droughts and storms due to climate change. Therefore, increased storage to improve water security for the Lachlan will enhance outcomes for our communities and provide protection from drought and flood.”

It's a matter of flood mitigation plus water security for Lachlan Shire residents. IMAGE: Condobolin flood November 2022. Facebook

Cost blowout

 Ms Jackson said the final cost of delivering this project was likely to be over $4 billion dollars which was 600 times some of the original estimates.

"Terms like significant, catastrophic, irreversible are used repeatedly in the expert business cases, it's just not foreseeable that a project with that level of environmental impact was ever going to receive planning approval. The beneficiaries of this project were likely to be less than 1,000 landholders and for $4 billion and catastrophic environmental impact that’s just not justifiable."

"While Wyangala is not viable, I recognise the challenges of water security, reliability and flood mitigation for Lachlan communities do not go away. We know there's a drought knocking on our door threatening the water security of towns across NSW which is why we are reviewing our strategies as a priority.

Mr Medcalf said council has known for some time that more storage is needed to secure towns and other productive water users in Central NSW.

"I support recommendations made in the NSW Government’s Business Case for raising the wall of Wyangala Dam that an expansion of the regional water grid is required. However, I am concerned that the Business Case did not fully consider the benefit of avoiding the cost of closing towns down due to water shortfall in their cost benefit analysis," he said.

Flooding near Condobolin in 2022

Feedback sought for new plan

The NSW Government will be seeking feedback on how it plans to address these issues in the draft Lachlan Regional Water Strategy, which will go on public exhibition from 20 September to 12 November 2023.

Minister Jackson said the decisions are made about the future of water in the Lachlan region will be based on evidence and state-of-the-art climate modelling.

"We want to support economic growth and balance different water needs, ensuring there's the right amount of water for the right purpose at the right time," she said. "I encourage everyone across the Lachlan region to provide their input when the draft strategy goes on exhibition, because feedback from councils, industry and the community will play a vital role in helping us determine the best way forward."

Mr Medcalf said an assumption that towns ‘will not run out of water’ is an oversight which is at odds with the lived experience of many water users in Lachlan shire.

"The region needs to continue to work with the NSW Government to ensure the full costs to our communities are considered during development of options to improve water security for the Lachlan,” he said