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A multilayered sharp interface model of coupled freshwater and saltwater flow in coastal systems: Model development and application

January 1, 1990

A quasi three-dimensional, finite difference model, that simulates freshwater and saltwater flow separated by a sharp interface, has been developed to study layered coastal aquifer systems. The model allows for regional simulation of coastal groundwater conditions, including the effects of saltwater dynamics on the freshwater system. Vertically integrated freshwater and saltwater flow equations incorporating the interface boundary condition are solved within each aquifer. Leakage through confining layers is calculated by Darcy's law, accounting for density differences across the layer. The locations of the interface tip and toe, within grid blocks, are tracked by linearly extrapolating the position of the interface. The model has been verified using available analytical solutions and experimental results. Application of the model to the Soquel-Aptos basin, Santa Cruz County, California, illustrates the use of the quasi three-dimensional, sharp interface approach for the examination of freshwater-saltwater dynamics in regional systems. Simulation suggests that the interface, today, is still responding to long-term Pleistocene sea level fluctuations and has not achieved equilibrium with present day sea level conditions.

Publication Year 1990
Title A multilayered sharp interface model of coupled freshwater and saltwater flow in coastal systems: Model development and application
DOI 10.1029/WR026i007p01431
Authors Hedeff I. Essaid
Publication Type Article
Publication Subtype Journal Article
Series Title Water Resources Research
Index ID 70015831
Record Source USGS Publications Warehouse