A numerical model for the prediction of long term well yield in an unconfined chalk aquifer

Abstract

Summary The prediction of the long term yield from individual pumped wells is one of the main problems to arise from the Thames Ground Water Scheme. A numerical method for solving this problem, more versatile than conventional non-equilibrium pumping test analysis techniques, is described. The method is based on the discrete space/discrete time radial flow model, developed recently by Rushton et al. (1974). Factors modelled include the detailed spatial distribution of aquifer parameters, a variable pumping rate, natural recession and wellfield interference effects. An outline of the fundamental hydrogeological aspects of the modelling work is also given.