Hydrosalinity Modeling of Suspended Sediments

Abstract

A submodel was added to the EPA Watershed Erosion and Sediment Transport (WEST) model to quantify salt release from suspended sediments in overland and channel flow, to determine their relative contribution in total salt loading in an arid climate, and to provide specific information for control program priorities. The WEST model simulates runoff and erosion from a watershed surface and routes the flow and sediment down a stream channel. The added salt release submodel was developed by the authors using data from samples collected from upland areas in the Price River Basin, a typical salt contributing basin within the Colorado River Basin. Thus the overall model estimates diffuse salinity loading from suspended sediments eroded in overland flow and transported sediments in the stream channel. Application of this model to a subbasin within the Price River Basin estimated that less than 1% of the salt load at Woodside near confluences of the Price and Green Rivers can be attributed to the suspended sediments and therefore that salinity control programs should concentrate on salt loading by subsurface flows.