2018 Reports

Using a Basin-Level Approach to Address Climate Change Adaptation
of Urban Water Supply: The Case of Santiago, Los Angeles, and Bangalore

Vicuña, Sebastian; Jamwal, Priyanka

This case study illustrates the importance of a basin-level perspective in urban water supply adaptation under climate change. Cities’ positions within river basins, headwater (Santiago), mid-basin (Bangalore), or outlet (Los Angeles), strongly influence available adaptation options, including water efficiency, reservoir management, interbasin transfers, and desalination. Santiago faces reduced snowmelt runoff and competition with agriculture, Los Angeles relies heavily on imported water with diverse supply sources, and Bangalore suffers from depleted reservoirs and unsustainable groundwater extraction. The study emphasizes that upstream efficiency measures can create downstream water scarcity, highlighting the need for integrated, basin-wide planning and coordination to secure urban water supplies.