Relationship of basin characteristics to selected water chemistry parameters in upper Carson River basin

Abstract

A study was conducted for screening the hydrologic-chemical characteristics which control the parameters of a basic flow-concentration equation. Sub-basin characteristics of geomorphology, geology, soils, and land use for fifteen sites in the Upper Carson River basin were quantified and related to flow-concentration parameters and ionic ratios of selected inorganic aqueous chemical components. Twenty-nine equations were developed, by use of a multiple regression computer program, which indicated relationships between basin characteristics and flow-concentration parameters. Influential characteristics for Carson sub-basins were compared to those delineated for Truckee sub-basins to determine the transferability of results. Findings indicate that characteristics controlling drainage rates are important in influencing the flow-concentration parameters and ionic ratios. Comparison of Truckee and Carson characteristics indicate similar hydrologic-chemical controls are at work in both basins although highly correlated generated multiple regression equations were poor predictors of actual values. This may be caused by the small number of basins studied. Extension of this approach to other river sub-basins will be made easier by results of this study.