INTRODUCTION
The first dam built in Turkey during the Republic era is the Cubuk -I Dam, built for the domestic water requirement of the city of Ankara. No serious activities in dam construction was observed until the end of Second World War except few low dams built for irrigation purposes. Since then however, an increase in construction of dams and hydroelectric power plants can be observed.
As the beginning of January 1999, construction of 193 dams have been completed and put in to operation. The 55 hydroelectric power plants associated with dams or canals-rivers constructed by DSI have total installed capacity of 10 573 MW, and annual average energy of 36 979 GWh. When the hydroelectric power plants constructed by the other organizations are considered, there are 104 HEPP's in operation with the total installed capacity of 10 215 MW, and annual average energy of 37 079 GWh.This figure is equivalent to 30 % of the total economic hydroelectric potential of Turkey.
Annual rainfall in Turkey varies between 220 mm to 2500 mm with an average of 642.6 mm.This corresponds to an average annual rainfall of 501 km3. Approximately 186 km 3of this amount flows as surface water. Studies made by DSI indicate that with the construction of 805 dams and 485 hydroelectric power plants (including the ones under construction, planning and in operation) it will be possible to regulate our rivers and make maximum use of them.
In case the above dams and hydroelectric power plants are completed, it will be possible to produce yearly 123,04 TWh of energy with an installed capacity of 34 740 MW and besides, great benefits will be obtained from irrigation, flood control and domestic and industrial use of water.
1 km3 = 1 billion m3 ; 1
hm3 = 1 million m 3
1 TWh = 1 billion kWh ; 1 GWh = 1 million kWh