Objectives and introduction

• Richards equation is often used to model variably saturated flow and is often considered as a benchmark for infiltration and flow comparisons. • Much research has been completed which looks at the effects of discretization on the Richards equation vertical infiltration solution, however, very little work has been done to examine the effects of discretization on lateral flow. • Ideally, simulation results should be reasonably consistent regardless of model grid discretization. • Evaluate the use of the Groundwater Flow equation to represent lateral soil zone flow. • Evaluate performance of new MODFLOW Interflow Stream Boundary for a variety of discretizations, hydraulic conductivities, and applied precipitation rates.