Sustainable groundwater management using a combined simulation–optimization approach

The Mediterranean region has been facing human and climate–change threats in the last decades. The current work, within the InTheMED PRIMA project, implements a groundwater simulation model in combination with optimization techniques and aims to elaborate informed alternatives in the decision–making process for the Tympaki study area.  Tympaki is located in the south of Crete and represents one of the most productive areas in the agricultural sector of the island. The economic activities combined with its location make it a very demanding region in terms of water needs. Most of this demand is met from the coastal aquifer and, more recently, from a reservoir. Climate change, the increase in temperatures and decrease in precipitation, cannot guarantee water resources of sufficient quantity and/or quality. To address these issues, an optimization analysis was conducted. The optimization problem was to maximize the pumping rates subject to a water table that improves or maintains the situation in the aquifer. In the case of Tympaki, this also helps solve the problem of saltwater intrusion. FEFLOW was used to simulate groundwater flow in the porous media and MATLAB application was used for optimization. Since groundwater flow is not a linear process, iterative simulation–optimization runs were performed in the framework of piecewise linear optimization. To avoid time–consuming procedures, customized GUIs were developed for better data processing in MATLAB. The simulation–optimization model was applied to recorded measurements and different time periods, as well as to regional climate model data. In addition, different water management scenarios were evaluated including alternative water sources, such as water from the reservoir or treated wastewater. The results are presented in online maps so that they can be disseminated among stakeholders and help inform all interested parties and enable more transparent decision–making.

This work was developed under the scope of the InTheMED and Sustain-COAST projects.

InTheMED is part of the PRIMA programme supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 1923. Sustain-COAST is funded by the General Secretariat for Research and Innovation of the Ministry of Development and Investments under the PRIMA Programme. PRIMA is an Art.185 initiative supported and co-funded under Horizon 2020, the European Union’s Programme for Research and Innovation.