Coastal aquifer model (ALS) theoretical documentation

The coastal aquifer model (ALS) is a part of the advanced computer system "ODYSSEYS", developed for water resources management. The purpose of this model is optimum management of coastal aquifers. A mathematical model of flow simulation is first developed in order to calculate the hydraulic head field, for given recharge and stress rates. Adopting the sharp interface approximation, the toe of seawater intrusion lens is calculated dependent on the solution of the hydraulic head field. Along with the mathematical simulation model an optimization procedure was developed based on Sequential Quadratic Programming. The integration of the simulation model and the optimization method resulted in a tool, capable of finding the optimum pumping rates of several wells subject to constrains, whose objective is to protect the wells from seawater intrusion. This model is designed so as to receive inputs from a Geographic Information System without requiring advanced knowledge of the underlying model details from the users.