Flow in aquifers with clay laminae: 1. The comprehensive potential

A description is given of steady flow in a system of homogeneously permeable aquifers that are separated by thin impervious clay laminae. Restriction is made to laminae that do not overlap one another. A steady state two‐dimensional Dupuit‐Forchheimer model is formulated to predict piezometric heads in the aquifers. The flow below the laminae may be confined or unconfined, and the possible occurrence of perched conditions above the laminae is taken into account. A new potential is introduced, with a gradient equal to minus the vectorial sum of the discharges in the upper and lower aquifers. This potential is referred to as the comprehensive potential and is determined by solving a boundary value problem of the Poisson equation. Application of the comprehensive potential makes it possible to establish heads along the edges of the clay laminae without the use of an iterative procedure. Two flow problems are solved as examples of the technique presented in this paper.