They are mainly small water bodies with an area of less than 1 km2. Only 32 lakes have a surface exceeding 10 km2. Winter discharges of water from the Toktogul Reservoir resulted in increasing the area of the Aydar Arnasay Lakes System, which is now the largest in Uzbekistan. With its area of 3,600 km2 and its storage capacity of 42 km3, this lake exceeds the water reserves of all other reservoirs. In 2008, it was added to the list of the Ramsar Convention on Wetlands of International Importance Especially as Waterfowl Habitat.