Adrian,Hickey;Lalantha,Senevirathna

Abstract Climate change is altering weather patterns, which affects water supply systems globally. More frequent extreme weather events like floods, droughts, and heatwaves are impacting the availability of raw water sources that supply cities. These events can lead to less water, higher demand, and potential infrastructure damage. Water agencies and utilities must develop resilient and adaptable systems to withstand shocks and stresses. Case studies demonstrating the impact of extreme weather on water quality are important for developing resilient water supply systems. This paper documents the challenges faced by regional New South Wales (NSW) in managing water quality and supply during extreme weather events. Effective treatment processes, such as ozone treatment and adsorption, are used to maintain drinking water standards during extreme weather. Water-efficient alternatives are provided, and critical water networks are inspected to identify leaks and reduce system demand. Local government areas must collaborate and share resources to ensure that towns can cope with future extreme weather events. Systematic investigation is needed to understand system capacity and identify surplus resources to be shared when demand cannot be met. Pooling resources could benefit regional towns experiencing both floods and droughts. With expected population growth in the area, regional NSW councils will require a significant increase in water filtration infrastructure to handle increased system loading. Continuous research, regular strategy reviews, and innovative approaches are essential to ensure a secure and reliable water supply during future extreme weather events.