The value of using contour maps and equipotential maps to define ground-water flow has been illustrated. First it is necessary to install a minimum of three wells.
Perforated pipe is used so that water can drain into the well from the surrounding saturated soils.
Three wells are needed for triangulation. Let's see just what is triangulation. In this figure, three wells are depicted in a triangular orientation. The perforated pipe or well screen for our example penetrates approximatelty one foot into the water table. A survey is done to locate the position of each well, both horizontally and vertically.