Author(s): Weiwei Yao; Minh Duc Bui; Peter Rutschmann
Linked Author(s): Peter Rutschmann
Keywords: River habitat; Sediment transport; Larva rainbow trout; Dynamic hydraulic modeling
Abstract: The Glen Canyon dam altered the Colorado River’s flow, temperature and sediment-carrying capacity, which challenges researchers'ability to inventory in-stream habitats and assess their sensitivity to environmental changes. This paper describes a method for river physical habitat inventory based on two-dimensional finite volume hydraulic modeling, a water velocity, depth, temperature and sediment transport based habitat classification system, and a Geographic Information System. The approach is applied to the Lees Ferry reach of the Colorado River downstream from Glen Canyon Dam, Arizona, USA in order to assess the sensitivity of dam to induced Rainbow Trout’s habitat variation. Modeling results for 12months are presented. Modeling results indicate non-linear, divergent relationships between physical habitat and over all habitat areas for Rainbow Trout. Comparisons of habitat duration curves for the whole year suggest that Glen Canyon Dam operations directly affect the trout population in the Lees Ferry reach and could be used to regulate fish abundance to limit potential negative effects of trout.