High Flow Experiments and Sediment Transport in the Grand Canyon

Steve Micko

Abstract: Flood experiments (FEs) originated in Glen Canyon Dam in 1996 (Olden et al., 2014). FEs are now conducted around the world for different (sometimes multi-objective) purposes. They were originally implemented to increase sandbar size and benefit the downstream ecosystem. The establishment of Grand Canyon National Park (GCNP) provided a strong incentive for the implementation of a reservoir operation policy that is growing in popularity. The new dam operation of Glen Canyon Dam are one of the first long-term flood experiment models. Previous FEs have successfully increased sandbar volume, but the practice has not been implemented over the long term. It is unknown whether FEs will sustain sandbar size. Neither are the direct effects on fish and vegetation populations well understood.