Australasian Science: Australia's authority on science since 1938

Water Additive on the Nose with Concrete Sewers

Research reported in Science has reported a way to save water utility companies hundreds of millions of dollars per year by reducing sewer corrosion – and the associated smell.

In research published in Science, Prof Zhiguo Yuan of the University of Queensland’s Advanced Water Management Centre reported that aluminium sulfate, a common coagulant added in the treatment of drinking water, can be a key contributor to the sulfate levels in sewage.

“This, in turn, is the primary source of hydrogen sulfide, which creates rapid concrete degradation and is the main cause of global sewer corrosion,” he said.

“This could be avoided by switching to sulfate-free coagulants at little or no extra cost compared with the large potential savings in sewer maintenance and corrosion costs.”

Coagulants are added in the drinking water treatment process to remove turbidity from the water.

Yuan said that sewer systems are one of the most critical infrastructure assets in urban societies. “Maintenance costs for these concrete sewers run into the billions of dollars a year across the world,’’ he said.