Abstract
Equations developed for a Green and Ampt type analysis for moving water table conditions in an initially saturated homogeneous profile of porous material and used previously in a falling water table study are now applied to a falling-rising water table sequence in a sand. The ability of the developed equations to be used in a system involving a directional change in water table movement relates to the inclusion in the equations of a term describing the initial saturated depth applicable to each new stage of the analysis. The predictive capability of the Green and Ampt approach for such a system is tested by comparing the results with those obtained from a computer-based numerical analysis. The relevant subroutine in the computer program required certain restructuring to accommodate the rising water table component. An interpolative hysteresis model is used to describe the accompanying wetting process with the material in question wetting up along primary wetting scanning curves.--Modified journal abstract.