Investigation of leakage at Ataturk dam and hydroelectric power plant by means of hydrometric measurements

Ataturk dam, with its 84.5 million m3 fill volume and 169 m height above the foundation, is one of the largest dams in the world. Its 1.2 million m2 grout curtain surface area is the largest constructed in the world to date. The Bozova fault crosses the dam axis in the left bank and extends towards the downstream valley. The grout curtain constructed in karstic limestone is 180 m deep in the thalweg and partially extends to 250–300 m depths in some local zones on both the right and left sides of the valley.In this study, we have investigated leakage at the Ataturk dam and hydroelectric power plant by means of hydrometric measurements. The hanging grout curtain indicates that leakage at Ataturk dam is of vital importance in defining the longevity of the dam. Hydrometric measurements, including discharge, temperature and electrical conductivity of springs and leakages, were carried out for 9 years periodically, in addition to monitoring performed before, during and after construction. The leakage increased as the reservoir water level rose seasonally but it was also discovered that this regular increase was not observed in the last three measurements. The decrease in leakage volume in the last three measurements proved the integrity of the grout curtain and the efficiency of the microsol grout works. Recent seepage levels are within design limits and therefore have no serious effect on the stability of the dam structures.