STREAM AQUIFER WELL INTERACTION

Abstract

Stream and rivers are important geological features, which control the occurrence distribution and water quality of surface and ground water. Surface and Ground water are not independent resources. There is an interrelationship between the two. During flood period flow takes place from stream to aquifer due to water level difference created between ground water table and stream stage, and aquifer gets recharged. Human interference also modifies the stream-aquifer interaction as lowering of water table in the aquifer due to pumping induces seepage from stream to aquifer. With this view, stream-aquifer-well interaction problem has become interesting and important for researchers. In nature, a single aquifer system rarely exists and most of the streams partially penetrate the upper aquifer. An aquifer is a part of system of aquifers separated from each other by less permeable confining layers.A stream in a multiaquifer system interacts directly with upper aquifer and indirectly with lower aquifers through a multiaquifer well if aquifers are separated by an aquicludes. In this study, discrete kernel approach has been applied to study the interaction among stream, aquifer and pumping well for constant and varying stream stage conditions. By applying the image-well, an infinite aquifer and well system has been transformed into a finite aquifer and well system. Study has been done for small diameter well, neglecting the well storage. Principle of superposition for linear system is used. In this d....