Recycled water key for future food security

Recycled waterUrban water utilities must prepare to provide more recycled water to food producers, according to a researcher at the Victorian Eco Innovation Lab (VEIL).

University of Melbourne Research Fellow Dr Rachel Carey said urban fringes may need to take over from rural foodbowls as the population increases and drying continues in the nation's south east.

“Places we think of as being major foodbowls – like the Murray Darling Basin – could have less water available in a more severe drying scenario,” she said. 

“We might need to look more to the peri-urban fringes of the city to be growing water-intensive products because of their potential access to recycled water.”

Carey leads Foodprint Melbourne, a collaborative project between VEIL (University of Melbourne), Deakin University and Sustain: The Australian Food Network. 

A recent project briefing paper highlights the role recycled water from urban water treatment plants, desalination plants and stormwater run-off could play in improving food security, as well as the amount of organic waste cities could provide.

Carey points to Melbourne's two main treatment plants, which produce recycled water near key vegetable-growing areas, but send 84% of that water out to sea.

“If you look at the amount of irrigation water that's recycled, it's around 1% at the moment,” Carey said. 

“I think the water industry have a real role here in terms of looking at the potential for making more recycled water available to food producers, particularly those on the fringe of cities where this infrastructure exists so close to water treatment plants.”

And Carey said urban water utilities should act now to ensure the nation's food security. 

“Utilities should be talking to farmers about what their needs are for recycled water, looking at the capacity that currently exists in the system and where that capacity might need to be extended,” she said. 

“They should also look at the infrastructure that's required to achieve that – whether that be greater storage capacity so that it's possible to store water in winter that can then be used in the growing season and looking at extending piping so that more farmers are able to access recycled water.”

It's not just longer term strategic planning that's needed, Carey said.

“It's a problem now – on the Mornington Peninsula there are farmers who are out of water who have had to stop production on their farms,” she said. 

The next phase of Foodprint Melbourne will look at policy solutions. 

The project has found it takes more than 475 litres of water to grow each person's food every day (excluding rainwater and water used in processing and manufacturing), which is roughly double the amount of water used in Melbourne homes.