Flow to a Well in a Multiaquifer System

Solutions are calculated for both steady and unsteady flow to a well in a multiaquifer system with N ‐horizontal aquifers. Aquifer and aquitard properties may vary from one layer to the next but are assumed constant in the horizontal direction. The solutions, which are expressed in closed form, require the solution of generalized eigenvalue problems for their numerical evaluation. It is shown that the matrices appearing in these eigenvalue problems are symmetric and positive definite, which means that the eigenvalues are real and positive and that the solution always exists. Finally, a solution is calculated for a numerical example.