Predicating evolution and transport of nitrate, acommon groundwater contaminant in agriculturalwatersheds, can reliably be done through numericalmodelling. This publication is an elaboration of thenumerical technique and simulation procedure fornitrate transport through a porous media. equationsgoverning fluid and contaminant transport through porous media aresolved numerically using the integrated finite difference method. the algorithms generated are then implemented using object oriented computercodes written in C++ programming language.the usefulness of the simulator in proved atvalidation stage where the simulated results are wellcomparable to field data obtained from the area ofsimulation. the manuscript is beneficial toprofessionals and students of environmentalphysics,civil and water engineering, and appliedmathematics.