Guiding urban water management towards 1.5 °C

Abstract

Reliable access to clean and affordable water is prerequisite for human well being, but its provision in cities generates environmental externalities including greenhouse gas (GHG) emissions. As policy-makers target opportunities to mitigate GHGs in line with the Paris Agreement, it remains vague how urban water management can contribute to the goal of limiting climate warming to 1.5 °C. This perspective guides policy-makers in the selection of innovative technologies and strategies for leveraging urban water management as a climate change mitigation solution. Recent literature, data and scenarios are reviewed to shine a light on the GHG mitigation potential and the key areas requiring future research. Increasing urban water demands in emerging economies and over-consumption in developed regions pose mitigation challenges due to energy and material requirements that can be partly offset through end-use water conservation and expansion of decentralized, nature-based solutions. Policies that integrate urban water and energy flows, or reconfigure urban water allocation at the river basin-level remain untapped mitigation solutions with large gaps in our understanding of potentials.