Water Resources Research Act Program

Details for Project ID 2011CO236B

Variables Controlling Reservoir Sedimentation in the Colorado Front Range

Institute: Colorado
Year Established: 2011 Start Date: 2011-03-01 End Date: 2012-02-29
Total Federal Funds: $5,000 Total Non-Federal Funds: $2,700

Principal Investigators: Ellen Wohl

Abstract: Sediment deposition can alter the storage capacity and operation of a reservoir. Numerous studies have been done on reservoir sedimentation, but site- and region-specific characteristics of sediment yield limit extrapolation of results between sites. One challenge in understanding reservoir sedimentation is that sediment yield to a reservoir varies spatially and temporally as sediment supply, storage, and mobilization from the contributing watershed change. This variability partly reflects regional characteristics such as lithology, rate of sediment generation, and mechanisms of sediment movement. The objective of this research is to evaluate the relative importance of parameters influencing sedimentation rate within and between reservoirs in the Front Range. The null hypothesis is that reservoir sedimentation correlates most strongly with the magnitude (spatial extent, frequency) of disturbance that alters land cover (e.g., forest fire) because disturbance can mobilize large volumes of sediment from the watershed. Increased disturbance by forest fire results in enhanced sedimentation in numerous sites across the Front Range. The alternate hypothesis is that reservoir sedimentation correlates most strongly with drainage area, relief, or elevation. The research will develop a GIS-based statistical model to determine the factors most important for reservoir sedimentation in the Front Range.