TR-87 : Analysis of flow to a dug well in hard rock area in an unconfined aquifer by Cell theory

Abstract

Dug wells are used extensively in hard rock areas for ground water abstraction. Development of ground water in these areas requires the knowledge of the dynamics of flow towards a dug well. In the present study, analysis of unsteady flow to a partially penetrating dug well has been made taking into account the well storage. Three dimensional groundwater flow model developed by Macdonald and Harbaugh as an extension to the cell theory proposed by Bear has been used for the analysis. The study has been carried out for different well penetration. Set of type-curves have been presented using which aquifer parameters can be determined. The performance of the well, i.e., contribution of well storage to pumping, has been evaluated for different penetration. The component of the well loss for different penetration has been estimated. The results presented are useful for the design of diameter and depth of of a well for required pumping rate and schedule.