Iskar Dam

Iskar Dam is situated between the mountains Plana, Lozenska and Ihtimanska Sredna gora. The dam is situated 37 km from Sofia, on the upper part of the gorge between Plana and Lozenska mountains. The lake has a length of 13,5 km, width 5,5 km and capacity of 673 million m3 water. The geological and topographic conditions are suitable for creation such a big reservoir. The narrow pass at the beginning of the gorge contains millions of old sandstones and the valley, where the previous settlements Gorni Passarel, Kalkovo and Shishmanovo were once, is wide enough. The rivers, which flow into the lake, gather water from an area of 1046 sq m with an average altitude of 1330 m above sea level and annual flow of 376 m3, from which 44% in winter and 56% in summer. The working volume of the dam is 520 million m3. The reservoir is equalizer of many years of the natural river’s flow. The water is intended for production of electricity (Passarel, Kokaljane), for irrigation of 48000  hectare in Sofia region and water supply for Sofia and improving the work of water-power stations in Middle and Lower Iskar downstream region. The dam is built of concrete ,with stone revetment, with two spillways and two discharging pipes in the middle stone-blocks. In a cross section the dam takes a shape approximately of a rectangular triangle, which base is dug in the solid rocks and the apex of the triangle coincides with the highest level of the gathered water; in the upper part the dam widens and makes the crown of the wall, upon which an asphalt road 6,5 m broad is built. In the wall are installed thermometer and marks with the task to follow the movements of the dam. The discharging of the water from the dam lake is carried out through 2 iron pipes with diameter 1800 mm, supplied with valves, which sink automatically, when the water in the lake raises above the limited level. Through the spillways could come 615 m3/sec water and through the main discharging pipes only 120 m3/sec water.The length of the dam on the crown is 204 m and the maximal height above the gorge is 84 m; the depth by the dam is 66 m. Close to the dam you can find restaurants, shops and cafés. The water surface of Iskar Dam takes an area of approximately 30 sq. km. The dam lake has been built from 1951 to 1956. The lower part of the lake is restricted area. In the upper part of the lake there are a wide range of possibilities for recreation, sailing, windsurfing, angling etc. Here is the most famous inland water resort with the name “The nest of the stork”(Starkelovo gnezdo)”, surrounded by restaurants, holiday - houses, sport-center etc.