Prof. Edie Zagona Department of Civil, Environmental and Architectural Engineering Director, Center for Advanced Decision Support for Water and Environmental Systems (CADSWES) University of Colorado at Boulder http://cadswes.colorado.edu/about/team/zagona River System Management: CADSWES Tools and Applications Abstract Rivers are the primary source of water for sustaining all aspects of human existence, notably food, energy, industrial fabrication, mining, sanitation and domestic life; flow regimes are controlled and waters diverted to provide these benefits. Rivers are also the arteries of the natural ecosystem, supporting complex biological systems, biodiversity, and land forms; unregulated flows best meet the needs of the natural system. In addition to the human vs. ecosystem competition, conflicts among human uses of water and between neighboring political entities sharing waterways add to management challenge. Management of rivers to sustain all of these benefits now and in the future is a major focus of organizations from global to local, and addresses the management on timescales from minutes to centuries. Climate variability and change further complicate long term management. Collaborative stakeholder processes and adaptive management concepts also must be considered. CADSWES for over 25 years has assisted organizations engaged in critical river management by providing new analysis techniques and decision support tools. The RiverWare and RiverSMART tools have been applied to river systems with a variety of management challenges. This talk will describe key features of the tools needed to address a range of specific river management problems and some applications of the tools to several river systems.