Future Scenarios for Greater Sydney’s Drinking Water Catchments

Secure water supplies are essential for modern cities amidst future uncertainty. Megatrends such as climate-change, shifting demographics and technological advancements will impact drinking water catchments, including those providing water for the 5 million people in Greater Sydney. As such, how can water authorities prepare today to protect drinking-water for tomorrow, even under previously unexperienced conditions? To address this question, the UTS Institute for Sustainable Futures partnered with WaterNSW to develop narrative scenarios of potential future directions and apply spatial modelling techniques to given physical changes for each scenario. 

Alternate future scenarios were informed by the megatrend's literature and UTS-ISF expert knowledge. Collaborative workshops allowed the incorporation of on-ground knowledge provided by WaterNSW staff, further refining the scenarios. These science-based narrative exercises were translated into future land use projections via a spatial model built from 30 years of historical catchment land use transitions. The modelling provided a tangible and interactive representation of what Greater Sydney’s drinking water catchments could look like in 2040 and 2060. 

Whilst no future scenario can be expected to eventuate exactly as described, they are useful tools for considering previously unexperienced conditions and testing potential solutions. As a result of the project, WaterNSW is already acting on one scenario addressing a carbon positive catchment. This involves investigating ways to generate revenue from carbon sequestration, biodiversity regeneration and supporting the low-carbon transition through renewable energy generation, transmission and storage projects. Across the scenarios the outputs are aiding planning and decision-making by water authorities today to protect drinking-water for future generations.