This paper examines patterns of drought impacts and institutional adaptation at three nested levels – water users, interstate management between sub-national governments, and international management between the US and Mexico. Drawing on primary data and in-depth field interviews across five geographic zones in the US and Mexico, the paper maps the evolution of key networks and venues for coordinating joint adaptation to drought and water scarcity. It examines the recent history of drought management alongside other key risks (principally groundwater development, urbanisation and climate change) to identify the key actors involved in drought adaptation and to assess the effectiveness of the venues used for joint adaptation decisions. The analysis suggests that adaptation at one level has impacts at other levels which requires effective vertical and horizontal coordination institutions as well as new modes of joint monitoring and decision-making. It further demonstrates how long-range, field-based observatories of environmental and institutional change can offer new perspective on the design and effectiveness of adaptation pathways in multi-jurisdictional, multi-level governance contexts.
