A MEANDERING STREAM, AQUIFER AND WELL INTERACTION

Abstract

In the area of modern hydrological and hydro-geological investigation, the Aquifer - Stream - Well Interference has got an important place. Spatial and temporal variations of groundwater and surface water interaction are important for studying, estimating and forecasting ground water and surface water resources. A stream comprising boundary of flow domain is often encountered in regional groundwater flow modeling. When a stream fully penetrates an aquifer and has considerable stream discharge, the stream is to be treated as a boundary of prescribed head. In such case, the region on each side of the stream behaves independently. However, a situation is rarely seen where a stream completely penetrates an aquifer. In case of partially penetrating stream" with considerable stream discharge in comparison to the seepage losses besides treating the stream as specific head boundary, the exchange of flow between the stream and the aquifer has to be introduced through boundary while modeling the groundwater flow. The recharge from a stream to an aquifer is proportional to a difference between the level of water in the stream and in the aquifer in the vicinity of stream. The coefficient of proportionality is recognized as reach transmissivity, which depends on shape of stream cross section besides the aquifer parameters. In this study, interaction among a partially penetrating meandering stream, pumping wells and homogeneous aquifer has been studied. The recharge from the stream during passage of a flood and the base flow after recession of the flood wave have been quantified. The advantageous location of well to cause induce recharge has been identified. i