Melbourne dam levels are nearing 80 per cent as $77m worth of desal water keeps pouring in

Water storage levels at Melbourne’s dams are nearing 80 per cent ahead of the wettest month of the year, with questions mounting about a $77 million desal order now flowing into catchments.

A $77 million desalinated water order placed by the Andrews Government has begun pouring into dams even as storage levels approach 80 per cent — and the wettest month of the year is still to come.

Fresh questions have been raised about the Andrews Government’s decision to pay for 125 billion litres of desal water this year, despite population stagnation and healthy dam levels.

Melbourne’s storage levels are now 10 per cent higher than the same time last year, with decent rainfall expected up until October – traditionally the wettest month of the year.

Acting Water Minister Richard Wynne defended the order as part of a bigger plan to keep storages at “healthy levels” and future-proof against drought.

But opposition water spokeswoman Steph Ryan said the decision was “embarrassing” when some dams were already at 100 per cent capacity and more rainfall was forecast.

“They are pushing unnecessary costs back on to households at a time they can least afford it by ordering desal water when it is not needed,” she said.

“Every drop of water ordered from the plant costs more money.”

Debate over the order – which Mr Wynne told a parliamentary inquiry was worth about $30 per household on average – comes as the Bureau of Meteorology forecasts wet months ahead for eastern Australia.

Inside Victoria's desalination plant. Picture: Jake Nowakowski

Over the past few years the government has placed large desal orders, arguing that population growth and long-term drier weather from climate change meant storages would dip again.

Mr Wynne said without desal water from recent years, storages would be at 59 per cent.
“We don’t just pray for rain, we manage our supplies to avoid water restrictions and prepare for drought, while still continuing to have the lowest water bills of any capital city in the country,” he said.

Mr Wynne recently told a parliamentary inquiry that the desal plant, which costs about $650 million to maintain even if no water is ordered, is viewed by government as “fundamental to our water security going forward”.

Liberal Democrats MP David Limbrick said at the hearing he understood the long-term strategy but couldn’t comprehend why this year’s order was so large, at 125 billion litres.

The government can order between zero and 150 billion litres every year.

Storages are currently 77.5 per cent full, with annual trends suggesting they could rise to 85 per cent full before summer.

Several smaller dams are full, while the biggest — the Thomson reservoir — is at 77 per cent.

Mr Wynne said desal was part of a “four-pronged attack” to deal with historically low catchment flows.

Other prongs included upgrading farming and irrigation systems and pipelines, using more recycling and stormwater to ease the burden on drinking water, and encouraging households to minimise water use.

“The desal has become a normal part of the water supply to keep storages at a healthy level,” he said.

“Population growth, clearly, and climate change are putting increasing pressures on our water supply.”