Seawater intrusion into coastal aquifers of Thrace and its impact on the environment

Seawater intrusion into aquifers in coastal flat areas constitutes a considerable factor of degradation of the natural environment and a restrictive agent for the development of those areas. The intrusion occurs in a great extent of the Strymon river estuary up to the Evros river estuary. Saline intrusion into fresh groundwater formations generally results inadvertently from man's activities, such as excessive pumping resulting in reduction or reversal of groundwater gradients and destruction of natural barriers that separate fresh and saline water, which disturb the existing natural hydrodynamic balance between sea and groundwater. The simultaneous study of the specific electrical conductance of groundwater, as well as the chloride‐bicarbonate ratio and hydrological properties of the various aquifers, makes the accurate prediction of seawater intrusion possible.