Climate Change: A Growing Threat to Wastewater Systems and Waterways in Australia

Climate change has increased Australia’s average temperatures and led to drier conditions in the southwest/ southeast, with more frequent years of below average rainfall. These changes pose significant challenges for the wastewater treatment sector, with flow-on effects to water-dependent ecological systems.

Hotter and drier conditions are predicted lead to reduced treatment plant flows, and a more concentrated wastewater. At the same time, reduced rainfall and increased evaporation will result in reduced flows in receiving waterways, and increased concentrations of “ambient background” toxicants. These changes in receiving waterways reduce the assimilative capacity of these systems generally, but particularly so for a more concentrated wastewater. Climate change is also predicted to result in increases in peak daily rainfalls, leading the potential for increased sewage overflows and associated impacts to waterways.

This presentation discusses the need for increased focus on the potential risks from treated wastewaters to receiving waterways under future climate conditions.