Community Research and Development Information Service - CORDIS


The Karla watershed in Thessaly, Greece has been studied. It was a valuable wetland in the Mediterranean belt until the lake was drained by a tunnel in 1962. From then on water quantity and quality declined steadily. Management schemes are now planned to restore pre-existing wetland functions. With a water balance we aim to assess their effectiveness. We have derived a conceptual water balance for 12 years between 1979-1990 from collected data. A hydrological simulation model was set up for cross-checking the results. Due to the complex Karla terrain and geology, we could only reproduce the larger contributions whereas the tunnel discharge has been overestimated. Nevertheless, we have identified the processes which caused the sharp drop of the groundwater table after 1984. The drop is mainly caused by a lack of rainfall whilst agricultural practices remained the same. Then already moderately increased abstraction rates could over-exploit the aquifer.

Additional information

Authors: KAISER C, JRC Ispra (IT);ZALIDIS G, Aristotle University of Thessaloniki, Faculty of Agriculture (GR);GERAKIS A, Aristotle University of Thessaloniki, Faculty of Agriculture (GR)
Bibliographic Reference: Paper presented: Operational Water Management, Copenhagen (DK), September 3-6, 1997
Availability: Available from (1) as Paper EN 40765 ORA
Record Number: 199711104 / Last updated on: 1997-09-16
Original language: en
Available languages: en