Finite Element Model to Describe Overland Flow on an Infiltrating Watershed

THE Finite Element Storm Hydrograph Model (FESHM) developed at VPI&SU was modified to ac-count for transmission losses from the overland flow plane. Transmission losses from overland flow were described by the governing continuity equation of surface flow. Appropriate boundary conditions and functional relationships were defined. Sinks along the one-dimen-sional flow strip often resulted in discontinuities in the flow that created computational difficulties in using the finite element numerical method. A procedure was de-veloped to circumvent these difficulties by defining con-tiguous units with continuous flow and the linkage re-quired when an element changed from a sink to a source or vice versa.