Shagan (lake, Abai Region)
Shagan (Kazakh: Шаған) or Chagan (Russian: Чаган)[2] is a lake in Zhanasemey District, Abai Region, Kazakhstan.The lake lies to the north of the confluence of the Shagan river, of the Irtysh basin, and its tributary the north-flowing Ashchysu.A few years later, a dam was built on the left bank of the river to control the water level in the reservoir that formed to the south.A 140 kiloton device was placed in a 178-metre-deep (584 ft) hole in the dry bed at the confluence of the Shagan and Ashchysu rivers.The crater was filled shortly after the nuclear blast by the water of the rivers and it is often referred to as "Atomic Lake" (Kazakh: Атом көлі).