TN-9 : Unsteady flow to a multiaquifer flowing well

Abstract

Using discrete kernel technique, analytical solution has been obtained for unsteady flow to a well tapping any number of aquifers which are separated by aquicludes and have different initial hydraulic heads. Results have been given for a well which is opened to three confined aquifers. Exchange of flow among the aquifers prior to and after pumping have been evaluated. The contributions of each aquifer during pumping have also been determined. The variation of composite hydraulic head at the well point with time has been obtained. It is found that when the aquifers have equal hydraulic diffusivity, the composite hydraulic head at the well point attains the near steady state value very quickly. It is also found that in a three aquifer system, when two aquifers have equal initial hydraulic head and same hydraulic diffusivity, the flows they receive from the aquifer having highest initial hydraulic head are proportional to their respective transmissivity values.