Suspended Sediment—River Flow Analysis

Abstract

There is increasing interest in suspended sediment as a water quality parameter because of its potential as a transport mechanism for pollutants and because of its possible effects on fish habitat. The application of bivariate probability distribution functions to represent the suspended sediment concentration‐water discharge data for the San Juan River at Bluff, UT is presented. This approach has several advantages over more traditional methods, including preservation of sediment concentration information and convenience for computer implementation. A bivariate log‐normal density function was found to adequately represent the San Juan River data. Average sediment yields were calculated using the closed form solution of the moment generating function, and compared to the results from the flow duration‐sediment rating curve method. The bivariate log‐normal density function was found to be a convenient, accurate method for parameterizing the frequency distribution of sediment concentrations and water discharges for the San Juan River.