San Francisco’s transformation into a global leader in onsite water reuse systems (ONWS) offers a compelling example of how cities can adapt to intensifying water scarcity. In this Science Talk, Ms. Nof Afghani explores how geographic constraints, prolonged drought, and ageing centralized infrastructure pushed the city to rethink conventional water management. What began as a modest 2012 local ordinance has since evolved into a pioneering model that reshaped the California Water Code and informed broader frameworks such as the National Blue Ribbon Commission for Onsite Non-potable Water Systems. Drawing on insights from the Eawag Lighthouse Project Report, this Science Talk traces how local innovation scaled into national influence.
The Science talk examines how San Francisco successfully expanded decentralized water infrastructure through the coordinated development of five interdependent pillars: physical system design, institutional frameworks, financial mechanisms, industry and market conditions, and public legitimacy. Rather than a purely technical transition, the city’s experience highlights the importance of aligning governance, incentives, and societal acceptance to enable sustainable change. By unpacking these dynamics, this Science Talk offers practical lessons for cities seeking to implement onsite water reuse as a climate adaptation strategy, demonstrating that effective urban water transformation depends on both integrated systems thinking and strong institutional collaboration.
Speaker
Ms. Nof Afghani
Fellow, Water Governance and Innovation Policy
