Optimization models in groundwater management, based on linear and mixed integer programming. An application to a greek hydrogeological basin

Abstract

The paper compares two optimization methods used in groundwater management, based on linear as well as on mixed integer programming (LP and MIP). The solution obtained of the combined simulation - optimization models, consists of three steps (Psilovikos, 1996): 1. Simulation model - MODFLOW , 2.Management model - MODMAN, 3.Optimization model - LINDOAn hydrogeological basin in Northern Greece, was used as a case study in this project. The collected data are based on 26 managed wells, for a period of 12 months (Psilovikos et al, 1996). in order to reduce the amount of calculations, only 4 managed wells were selected for a period of 3 months. The results obtained from the solution with the two methods above, are : a) both models satisfy the same piezometric and balance constraints, b) the MIP model is more complicated and the feasible region of solutions is more constrained than the LP one, because a number of integer constraints is included, so the LP model can be considered as the relaxed version of the MIP one.