Some remarks on water resources degradation and ground fissures formation in Thessaly, Greece

(i.e. low precipitations) affecting the Aegean Region and the huge increase of the cotton cultivation in large sectors of Thessaly, central Greece, forced people to search for new water resources to provide the needs. Accordingly, during the seventies and eighties, the synergy of the natural phenomenon with the inappropriate agricultural choice, was coupled with the drilling of an almost uncontrolled number of boreholes across the entire area. These water-wells that mainly exploit the alluvial multi-aquifer system of the Larissa Plain caused a significant downdrop of the piezometric level that critically exceeded the capacity to regenerate the underground natural hydraulic conditions. As a consequence, a quantitative and sometimes qualitative degradation of the water resources occurred. During the nineties, numerous ground fissures have been documented within the Larissa Plain. These superficial features have locally roduced important damages by creating open fractures in houses, stores and infrastructures, dislocations and hollows across roads and even caused a road accident. The occurrence of the phenomenon more than once, the associated damages and the awareness of the general seismogenic character of Thessaly deeply frightened the inhabitants of the region and their Authorities. A common opinion is that the production of fissures is straightforwardly and directly elated to the general lowering of the piezometric level (Soulios, 1997). In the present research, we revised all available data in order to better understand the phenomenon and the cause-effect relationships.