IDEALIZED MATHEMATICAL MODELLING OF AN AQUIFER

Abstract

Ground water plays an important role in the development and management of water resources. There-fore, realistic evaluation and prediction of ground water movement in aquifers is necessary. Ground water modelling techniques are becoming an essential tool for evaluation and prediction of aquifer behaviour. An idealized mathematical model of the aquifer system between Eastern Yamuna Canal (EYC) and Yamuna river from Tajewala to Okhala has been developed. The aquifer boundaries are idealized into straight lines and wells are grouped into pumping centres. The mathe-matical model has been developed using image well theory and Theis equation. The model incorporates the effect of seepage outflow and inflow across the aquifer boundaries as well as the effect of recharge due to rainfall penetration and return seepage. A versatile computer program embodying the above model has been developed. The model has been calibrated by minimising the cumulative error between predicted and observed heads at all the nodal points in the aquifer. Despite severe idealizations and simplifications, the perfor-mance of the model is very good as can be seen from satisfactory matching of predicted and observed contours in the aquifer under study.