Scientists at Arizona State University say there is a goldmine in sewage waste

IT is the most unlikely of places to strike a fortune but scientists say they have found heaps of gold in sewage.

Scientists say metals including gold can be found in sewage sludge. Picture: Sebastian Derungs

IT is the most unlikely of places to strike a fortune but scientists say they have found gold in sewage. Yes, gold. In sewage.

Scientists at Arizona State University say there could be as much as $13 million worth of metals in the sludge produced by a city of one million people each year, including $2.6 million in gold and silver.

Science Mag reported metals have long been known to exist in sewage but what the good folks at ASU have done is quantify its value.

Sewage mixes toilet water with effluent from industrial manufacturing, storm run-off and anything else flushed down the drain.

The scientists took sludge samples from around America and measured the metal content with interesting results.

Lead author Paul Westerhoff said extracting the metals could prove worthwhile and that one city in Japan is already doing so. The people of Suwa in Nagano Prefecture reportedly collect two kilograms of gold from every metric tonne of ash left after burning sludge.

Yale University engineer Jordan Peccia told Science Mag there is literally a gold mine running underneath big US cities.

“We’re not going to get rid of this sewage sludge,” Peccia said. “We need to make this push where we stop thinking about it as a liability and instead we think about it as a resource. And anything we can find in sewage sludge that’s valuable, it’s good.”

The researchers next plan to determine whether extracting metals is cost-effective or technically-viable.

“We think it is,” Westeroff said.

Originally published as Scientists at Arizona State University say there is a goldmine in sewage waste