M. Mirabzadeh - Department of Irrigation Engineering, College of Agriculture, University of Tehran, Karaj, Islamic Republic of Iran.
K. Mohammadi - Department of Irrigation and Drainage Engineering, Tarbiat Modarres University, P. o. Box:۱۴۱۱۵-۳۳۶, Tehran, Islamic Republic of Iran.

The partial differential equations for water flow and solute transport in a two-dimensional saturated domain are rendered discrete using the finite difference technique; the resulting system of algebraic equations is solved using a dynamic programming (DP) method. The advantage of the DP algorithm is that the problem is converted from solving an algebraic system of order NC(NL-۱) NC(NL-۱) into one of solving a difference equa-tion of order NCNC over NL-۱ steps and involving NL-۱ matrix inversions of order NCNC. The accuracy and precision of the solutions are shown by comparing the results with an analytical solution and calculation of mass the balance. In addition, the perform-ance of the DP model was compared with the results of the MOC model developed by US Geological Survey. In all cases, the DP model showed good results with sufficient accu-racy.

Numerical model, Dynamic programming, groundwater, Solute transport