Lake Assad is a reservoir on the Euphrates in Ar-Raqqah Governorate, Syria. It was created in 1974 when the Tabqa Dam was closed. Lake Assad is Syria's largest lake with a maximum capacity of 11.7 cubic kilometres (2.8 cu mi) and a maximum surface area of 610 square kilometres (240 sq mi). A vast network of canals uses water from Lake Assad to irrigate lands on both sides of the Euphrates. In addition, the lake provides drinking water for the city of Aleppo and supports a fishing industry. The shores of Lake Assad have developed into important ecological zones.