Modeling The Saltwater Intrusion Phenomenon In Coastal Aquifers - A Case Study In The Industrial Zone Of Herakleio In Crete by

Salinity is a common problem in Greek islands, especially, during the summer period
when the saltwater intrusion becomes more severe due to extensive over pumping. In the
past few years, the industrial zone of the City of Herakleio in Crete appears to have an
increasing water demand as result of the continuous industrial development. The water
demand is mainly cover from groundwater resources. The karstic nature of the geological
formations beneath the industrial zone has a great impact in the overall hydro-geological
characterization of the aquifer. Also the expansion of the saltwater front into the aquifer is
hard to be determined due to the presence of innumerable cracks, which act as closed
conduits of saltwater and the density variation between the saltwater and the fresh water.
The main objectives of this study were to map the geology and the salinity zone in the
area based on geophysical measurements. The industrial zone lies on a karstified
limestone with several faults that need to be delineated. Mapping of the area revealed
also specific places that were recommended for observation wells. In the future, these
wells are planned to be used as injection wells for the restoration of the aquifer. Another
objective of this study was to propose different management scenarios to inhibit the
saltwater intrusion front further inland. In this paper, scenarios that suggest artificial
recharge of fresh water are presented in order to raise the groundwater level and to
create a groundwater flow towards the sea.