Assessment of different management scenarios to control seawater intrusion in unconfined coastal aquifers

Abstract EN

The present study examines the capability of different hydraulic barriers to control seawater intrusion in coastal aquifer systems.

Different management scenarios including abstraction of intruded saline water near the coast, artificial recharge of the aquifer with the good quality water, and combination of abstraction and recharge are simulated in unconfined aquifers and optimally analyzed using a simulation-optimization (S/O) approach.

In each scenario of control, the trade-off between two objective functions: minimization of costs of management processes and minimization of total amounts of salinity in the aquifer, was obtained using the developed S/O framework.

The recharge is implemented using a surface basin and therefore unsaturated flow theory is utilized in the simulation.

Comparison of the developed management models suggests that the pumping of brackish water near the coast and its use for human and industrial consumption after desalination is an efficient method to control saltwater intrusion in deep aquifers.

However, for aquifers with shallow hydrogeological settings, a new combined methodology is found to be the most cost-effective method in controlling saltwater intrusion.

In this combined approach, the recharge by pond water is coupled with continuous pumping of intruded saline water near the coast followed by its desalination and use.