Study of Prespa Lake’s hydrology using isotopes and other relevant techniques

Abstract

On the borders between FYR of Macedonia, Albania and Greece there are three lakes: Ohrid Lake, and Big and Small Prespa Lakes. Galichica and Dry mountains separate the lakes. Several Projects (Supported by IAEA, NATO, EU, UNESCO and others) have been dealing with the determination of the water balance and the protection of Prespa and Ohrid Lakes with special attention to the explanation of the decreasing of the Prespa Lake water level, in excess of 8m in the last decades. Investigations using Environmental isotopes and artificial tracers showed that Prespa Lake's waters drain through the Galichica and Dry mountains into Ohrid Lake. By using an appropriate model, relevant hydrogeological, hydro meteorological data, satellite images and a computer program which implements an adequate recursive and exponential equations, the volume of the underground aquifer below Galichica Mountain and the volume of the Prespa Lake have been calculated.