Record low rainfall in regional Victoria means the controversial $6.1 billion Wonthaggi desalination plant might finally be turned on.

Victorians pay $1.8 million each day for the plant to sit idle but the government is looking at using it to top up Melbourne’s storage capacity and send water to the Mallee and Wimmera.

“Using the water infrastructure that we have always said is an insurance policy against these sorts of drought like conditions – that just makes sense,” Premier Daniel Andrews told reporters.

But turning the plant on means water bills look set to go up again.

“There’s a considerable cost involved. The cost, however, of communities running out of water is obviously much much higher than that,” Mr Andrews said.

The Wimmera and Mallee regions have reportedly had their lowest rainfall on record over the past 14 months.

Opposition leader Matthew Guy said it was bizarre to go straight to turning on the desalination plant when other options were available.

“The Labor government need to look at other measures before just defaulting to the most expensive water in Australia,” Mr Guy told reporters.

Labor signed the contract for the Wonthaggi plant in 2009 and defended the need for the project even as costs blew out and the plant sat idle.

Melbourne Water’s total storage levels are at 74.3 per cent.

Greens leader Greg Barber said it would make more sense to spend money saving water around homes.

“It’d be a hugely expensive option to send desalinated water off to agricultural use,” he told reporters.

Mr Barber said water consumption per head has gone up in recent years.

By Angus Livingston