Considerations for Assigned Water after Expiration of the 2007 Guidelines Kathryn Sorensen1, Sarah Porter2, Anne Castle3, John Fleck4, Eric Kuhn5, Jack Schmidt6, Katherine Tara7
Executive Summary As Colorado River supplies and demands reach razor-thin margins, new tools to provide adaptive capacity will play a critical role in sustaining communities across the West. We must reduce our consumption of water, while finding ways to cushion the impact. One of the most innovative tools for doing this, developed over the last two decades, is “Assigned Water” - giving users the ability to store conserved water earmarked for their own future use. Originally developed as “Intentionally Created Surplus” in the 2007 Colorado River Interim Guidelines, Assigned Water has been revised and expanded through U.S.Mexico Treaty Minutes and as part of the 2019 Drought Contingency Plan. While conceptually simple and demonstrably valuable - a savings bank for conserved water - it is crucial to get the policy tools right as Colorado River management rules evolve. For agencies granted access to the tool, Assigned Water provides important adaptive capacity to prepare for and manage shortfalls on a volatile river with shrinking supplies. But nearly two decades of operational experience also have exposed unintended consequences. With Assigned Water likely to play a critical role in basin management going forward - including its potential expansion to the Upper Colorado River Basin - it is important to review the strengths of the existing program, and essential lessons learned, to guide the development of river management policies after the current operating rules expire at the end of 2026.
Director of Research, Kyl Center for Water Policy, former Director, Phoenix Water Services Director, Kyl Center for Water Policy 3 Senior Fellow, Getches-Wilkinson Center, University of Colorado Law School, former US Commissioner, Upper Colorado River Commission, former Assistant Secretary for Water and Science, US Dept. of the Interior 4 Writer in Residence, Utton Transboundary Resources Center, University of New Mexico 5 Retired General Manager, Colorado River Water Conservation District 6 Director, Center for Colorado River Studies, Utah State University, former Chief, Grand Canyon Monitoring and Research Center 7 Staff Attorney, Utton Transboundary Resources Center, University of New Mexico 1 2