Combined optimisation simulation model for groundwater management policy options

Abstract

Water resources system being quite complex in-nature, modelling involves several variables and parameters. A large number of models have been developed for analysis of water resources system. Most of the models developed are of simulation optimisation type. In general water management models which generally use the governing partial differential equation of now, the problem is formulated using either finite difference techniques or finite element method. In this paper, a hybrid model is formulated which simulates the groundwater system and optimises the same. The model developed has been used to study the effects of variation in pumping factors on the optimal values and on the yearly yield from the system, for a chosen pattern of pumping. The model has been analysed for three different boundary conditions. The aquifer model is descritised into 64 grids and a particular pumping pattern is chosen in the present study. The governing partial differential equation for groundwater now is reduced to algebraic linear equations using finite differences scheme and they are then embedded as a set of constraints in the model. For the chosen pumping pattern, the pumping factor plays a key role, depending on the boundary conditions, in achieving an optimum solution. Here, minimisation of heads is considered for optimisation. The model helps in simulating a complex groundwater system and evaluating certain policy for groundwater management.