He has worked with urban water, wastewater, stormwater, and related energy and greenhouse gas issues since 1990. His work addresses urban water security, water-energy nexus, and circular economy . He creates collaborations, tools, models and knowledge to address all flows of water – and related energy - into, out of, and within cities. This enables evaluation and management of key concepts such as: (i) net zero carbon water cycle, (ii) hybrid, decentralised and integrated systems performance, and (iii) sustainable urban design and planning.