Aydarkul is a large drainage lake in the north-eastern part of Uzbekistan. It is an artificial reservoir in the Aydar-Arnasai Lake System, covering a total area of 4000 km². The system includes three lakes with brackish water (actually Aydarkul, Arnasai and Tuzkan). Lakes are located in the saline basin of the southeastern part of the Kyzylkum desert. The length of Aydarkul lake is more than 200 km, the width in some places reaches up to 40 km. Aydarkul lake starts from the Tashkent region of the Syrdarya River, and ends in the desert of the Navoi region in front of the Nurata Mountains. There are many representatives of the Asian fauna in this region. Among them: mammals (eared grass-snake, turtle, fox, hare, wolf, gazelle, saiga, boar, jackal, ground squirrel, jerboa), reptiles: (sand python, Central Asian cobra, etc.), birds: pelican, swallow, Black vulture, large turtledove, pheasant, seagull, quail, partridge etc.). And there are more than 30 species of fish in Aydarkul: pike, roach, carp, barbel, catfish, pike perch, perch, snakehead, common carp, asp and others.
Until the middle of the last century, the Arnasai lowland (also called the Hungry Steppe) remained a dried salt lake for most of the year. Only in the spring, in a not very extensive lowland for a short time Tuzkan lake appeared, which completely disappeared with the onset of hot weather.
In the early 1960’s, the Syrdarya was dammed up. At the same time, Chardarya hydroelectric power station was built. Locks were put to control the water level, but when in 1969 a heavy flood occurred, the floodgates were opened, as the capacity of the dam was not enough. From February 1969 to February 1970, almost 60% of the annual flow of the Syrdarya effluent (21 km³) was sent from the Chardarya reservoir to the Arnasay lowland. As a result, a lake was formed. Since 1969, Aydarkul regularly received an influx from the Syrdarya, if the Chardarya reservoir flowed through the dam. So, the Arnasay lowland gradually filled with water and the second largest lake in the region (after the drying of Aral Sea) was formed. In 2005, there were 44.3 km³ of water in Aydarkul. Today the area of the lake is about 3000 km ². Its length is almost 250 km, and the width is up to 15 km.
Many kinds of fish were imported to the lake, including carp, pike perch, bream, catfish, asp, chechen, snakehead - these fishes are serving now as the basis for fishing. From 760 to 2,000 tons of fish is extracted per year in the system of lakes. There are no underwater currents on the Aydarkul Lake. The further to the west, the water is salt. Mineralization is more than 8 grams per liter in the west. And in the estuaries in the east is 3-5 grams, which creates a comfortable environment for biologic life. Suitable conditions, allows the lake to give a third of the entire fish of the republic, and is considered as a fish farm.
The fauna of Kyzylkum is supplemented by a lot of waterfowl that fly here from the Aral Sea.
Aydarkul is located in the distance from inhabited places. There only 345 families, that are living near the lake (about 1760 people).
The area of Aydarkul lake has great potential for fishing, nomadic pastoralism, and tourism.