An Assessment of Reservoir Density Currents and Inflow Processes

Abstract : Since tributary inflows are usually the major sources of nutrients and other materials affecting reservoir water quality, techniques for predicting the characteristics of density currents can help the U. S. Army Corps of Engineers regulate the quality of reservoir and release waters. This report provides a literature review of density current predictive techniques, in which field observations, factors inhibiting prediction, and water quality implications are discussed and predictive techniques are presented and analyzed. Specific equations for predicting plunge point location, initial mixing, interflow thickness, propagation speed, and underflow entrainment are developed and compared, and certain ones recommended for use. A mathematical method for determining water density, example computations illustrating how to use the recommended predictive equations, and a relevant computer algorithm to be used in a one-dimensional water quality model (e.g., CE-QUAL-R1) are presented in appendices.