Viewpoint – Urban water conservation and sustainability in the Colorado River Basin

Many cities around the world are facing the challenges of freshwater decline and groundwater degradation, compounded by population growth. In the southwestern United States, these challenges are amplified. In that region, many growing cities depend on water from the Colorado River Basin, which is faced with aridification and record-low surface water supplies. Despite these unprecedented trends in Colorado River flows, however, many basin cities are enhancing their water security through a combination of supply diversification and water conservation. We draw from key academic and practitioner studies to better understand which conservation strategies are employed, how water providers evaluate the effectiveness of these strategies, and what role urban water conservation has played in the Colorado River Basin. Our examination of the contributions and limitations of urban water conservation under Colorado River Basin drought conditions reveals how the political dimensions of urban water conservation influence the ability to fully realise the potential of conservation in broader basin governance and sustainability. We call for improved assessment and monitoring of conservation efforts, advancement of holistic approaches, and the addressing of key political and equity dimensions as ways to improve urban water conservation efforts and, more realistically, situate them in the context of basin wide sustainability.