Water links communities, ecosystems, and economies irrespective of political borders. This is evident in North America, where the United States, Mexico, Canada, and Indigenous nations share rivers, aquifers, and coastlines. These shared water resources sustain communities and industry, but sharing brings challenges. As pressures from population growth, climate, and economic development intensify, cross-border collaboration will continue to form the foundation for managing border water resources.
This year’s Arroyo explores the topic of water and borders, building on discussions from the 2025 WRRC Annual Conference, Shared Borders, Shared Waters. The publication highlights the history of water cooperation involving Arizona, the United States, Mexico, Canada, and Indigenous Nations while examining current efforts to expand, conserve, and protect shared water resources through public and private partnerships. This Arroyo aims to provide readers with a clear understanding of how cross-border collaboration is shaping water management today and how partnerships can ensure equitable access to clean, reliable water.