Application of linear programming and differential evolutionary optimization methodologies for the solution of coastal subsurface water management problems subject to environmental criteria

Summary: In the past optimization techniques have been combined with simulation models to determine cost-effective solutions for various environmental management problems. In the present study, a groundwater management problem in a coastal karstic aquifer in Crere, Greece subject to environmental criteria has been studied using classical linear programming and heuristic optimization methodologies. A numerical simulation model of the unconfined coastal aquifer has been first developed to represent the complex non-linear physical system. Then the classical linear programming optimization algorithm of the Simplex method is used to solve the groundwater management problem where the main objective is the hydraulic control of the saltwater intrusion. A piecewise linearization of the non-linear optimization problem is obtained by sequential implementation of the Simplex algorithm and a convergence to the optimal solution is achieved. The solution of the non-linear management problem is also obtained using a heuristic algorithm. A Differential Evolution (DE) algorithm that emulates some of the principles of evolution is used. A comparison of the results obtained by the two different optimization approaches is presented. Finally, a sensitivity analysis is employed in order to examine the influence of the active pumping wells in the evolution of the seawater intrusion front along the coastline. [Copyright &y& Elsevier]