Groundwater Flow in a Sandy Tidal Beach: 1. One‐Dimensional Finite Element Analysis

A 31‐day time series of observations of beach water table and tidal fluctuations was obtained from 13 wells along a profile perpendicular to the shoreline at Virginia Beach, Virginia. Finite element techniques were applied to solve the one‐dimensional, unsteady state, nonlinear equation for groundwater movement. For the finite element analysis, the semi‐infinite mass (unconfined aquifer) had to be replaced by a finite mass. The boundary conditions were found from the field data by directly solving the flow equation with a finite difference technique. The finite element method, using the variational principle, provided a reasonable solution and afforded economy in computer time. Field data were compared with the corresponding finite element solution. The results indicate the general accuracy of the methodology.