APPROXIMATE METHOD FOR QUANTIFYING LATERAL SEEPAGE TO AND FROM DRAINED FIELDS.
An approximate method for calculating lateral seepage to and from a drained field was obtained by simutaneously solving an equation for flow between uneven ditches with steady surface infiltration and a radial flow equation. The method was tested against finite element solutions of the Richards equation for steady state and transient drainage conditions. Good agreement was found between the approximate and finite element solutions for steady state conditions. The approximate method slightly underestimated the maximum and average water table elevations in both the high and low ditch cases. For transient drainage the approximate method estimated water table drawdown rates greater than the numerical solutions. Since the approximate method compared well to the numerical solutions, it was incorporated into the water management model, DRAINMOD.
author list (cited authors)
Chescheir, G. M., Fipps, G., & Skaggs, R. W.