Incorporation of Total Stress Changes into the Ground Water Model SUTRA

Abstract

Abstract To model ground water flow in a shallow aquifer underlying a salt marsh, the impact of total stress changes due to tidal loading of the marsh surface on the piezometric head within the aquifer must be considered. If the deformation of the porous medium is negligible, a ground water flow model may be modified to account for the changing total stress. The incorporation of these modifications into the U.S. Geological Survey (USGS) numerical model SUTRA is discussed, and example problems for which analytic solutions are available are presented to demonstrate the behavior and validity of the modified model. In addition, the form of the specific pressure storativity term used in the SUTRA model is discussed and modifications of this form are suggested.