De-risking water supplies in a climate-constrained future

Written by Kim Crozier, Senior Policy Advisor, Strategy & Policy
Infrastructure Victoria

The Millennium drought significantly changed water management and urgently propelled authorities to invest heavily in a desalination plant to shore up Victoria’s water supplies. It also paved the way for Victoria to use a variety of technologies and water sources, including recycled water, stormwater and groundwater.

As Australia confronts the long-term challenge of climate change, water planning and system design need to adapt to secure water supplies in the medium to long-term.

So what does this mean for Victoria’s water supply and environment, and what are the broader implications for policy makers?

As the latest report by the Intergovernmental Panel on Climate Change (IPCC) highlights, Victoria’s dams and rivers can expect less rainfall. This increases the risk of water shortages, and stormwater flooding risks that cause drainage and sewerage damage.

Likewise, more frequent and intense bushfires increase the risk of ash and debris contaminating the water supply. Droughts are also predicted to be more intense across Australia. These risks escalate under a high warming scenario.

Natural disasters on average already cost the Australian economy $38 billion per year. Deloitte Access Economics conducted modelling this year showing that even under a low emissions scenario these costs could rise to $73 billion by 2060.

This is why it’s essential the Victorian Government moves to limit the risk of climate change impacts on infrastructure and communities by taking further action to de-risk and build resilience into planning and decision-making.

Infrastructure Victoria included recommendations for the water sector to better plan and manage the state’s water supply in the updated 30-year strategy; Victoria’s infrastructure strategy 2021–2051.

Planning for climate change impacts

Current government forecasts anticipate water supply shortages could emerge in Melbourne as early as 2028 under a high population growth and high climate change scenario. But the water sector is proactively seizing opportunities to address the impacts of climate change - actively researching new technologies and exploring ways to reduce emissions while addressing implementation barriers.

Water supply planning  guidelines  take into account low, medium and high climate change scenarios coupled with the impact of population growth and water use behaviour.

While this is a great start, Infrastructure Victoria believes that undertaking a contemporary and comprehensive assessment of climate risks and the consequences for infrastructure would provide a better understanding of risk and identify options to further reduce those risks.

Considering a range of scenarios when planning and assessing infrastructure means the Victorian Government can have more confidence that projects and their supporting investment will stack up in challenging circumstances.

Looking at the role of recycled water

It is timely that the Victorian Government looks at the role of desalination, stormwater and recycled water to help fill the gap when rain isn’t falling.  Recycled water and stormwater can become major water supply augmentation options and recycled water has more predictable quality and quantity than treated stormwater. Considering all water supply options equally would ensure we provide communities with the most affordable, sustainable and efficient sources of water.

That’s why we’ve recommended that the government address barriers to the safe use of purified recycled water for drinking. This includes continuing community education to improve water literacy, commissioning studies into the safety and efficacy of using purified recycled drinking water and looking at better regulatory frameworks to manage health risks.

We would also like to see clearer lines of responsibility for the management of our urban water systems and supply to support future investment decisions.

Securing Victoria’s water supplies in a climate-constrained future will require collaborative and integrated planning, ongoing community engagement and clear investment and funding arrangements.

Ambiguous responsibilities can impede responsive and considered investment decisions, causing delays at times of ample water supply, or rushed and potentially unwise decisions when water is scarce. Assigning a body to take ownership of major system augmentation would support fit-for-purpose and transparent investment decisions.

Our research suggests that delegating investment decisions within the operating scope of public water corporations, would also support more efficient and effective long-term planning and investment.

The Victorian Government should also clearly allocate roles and responsibilities for urban water systems and major supply augmentation planning, recognising that ultimate responsibility rests with them.


Infrastructure Victoria Acting CEO Jonathan Spear will join the ‘Are We Ready? Preparation, Recovery and Changing Communities panel’ at the 2022 VicWater annual conference on Friday 11 February.

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