Scientists say system to treat contaminated wastewater offers a model for ensuring food security in a fast-warming climate

All it took to turn the murky, heavily polluted waters of South Africa’s Stiebeuel River into a resource clean enough for irrigating a community’s vegetable plots was a collection of stones, heat-treated wood and sand.

Without chemicals and using renewable energy, researchers from the University of Cape Town are cleaning 36,000 litres of water, polluted by sewage, chemicals, and traces of drugs and medication, every day to make it usable for growing food in a fast-expanding informal settlement along the course of the river.

Successful legal challenge raises questions about hundreds of floodplain harvesting licences issued by former Coalition government

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The New South Wales water regulator has cast doubt over its ability to prosecute potential water theft due to uncertainty about the validity of licences governing billions of litres of water entitlements in the state’s north.

It follows a successful legal challenge brought by a group of irrigators in the state’s north-west which found 11 floodplain harvesting licences issued by the former Coalition government were invalid.