EXCEL SOLVER USED AS A TOOL FOR GROUNDWATER MODELLING

Abstract

The use of groundwater models is prevalent in the field of environmental hydrogeology. Groundwater flow,
fate, and transport models have been applied to investigate a wide variety of hydro geological conditions. Groundwater
flow models are used to calculate the rate and direction of movement of groundwater through aquifers and confining
units in the subsurface. Fate and transport models estimate the concentration of a chemical in groundwater
beginning at its point of introduction to the environment to locations down gradient of the source. Fate and transport
models require the development of a calibrated groundwater flow model or, at a minimum, an accurate determination
of the velocity and direction of groundwater flow that has been based on field data.
The present work presents a simple ground water modeling spreadsheet template developed in Excel with macros
written in Visual Basic for Applications (VBA). It is based on Finite Difference method and can be used to model an
aquifer of any shape and size. The given template can be expanded to build groundwater flow models of virtually
unlimited number of nodes. The final modelled heads, at each node, can be output as XYZ file, which can be girded
by any contouring software to produce contour maps and 3D surfaces. By using excel solver we can minimize the
error, thus get the optimal solution. Mat lab coding was used to show the effect of pumping on water table.