Lake Chagan
Lake Chagan () or Lake Shagan (, Şağan), also known as Lake Balapan, is a lake in Kazakhstan created by the Chagan nuclear test on January 15, 1965, which was conducted as part of the Soviet Union Nuclear Explosions for the National Economy program. A 140 kiloton device was placed in a  hole in the dry bed at the confluence of the Shagan and Ashchysu rivers. The blast created a crater  across and  deep with a lip height of ; it is often referred to as "Atomic Lake" (). The water continues to be radioactive - about 100 times more than the permitted level of radionuclides in the water.

The lake's water comes from the Shagan River, a tributary of the Irtysh River. The lake was filled by the Soviet Union shortly after the nuclear blast. The crater lake's volume is approximately . To the south, the rim of the crater holds back the waters of a second reservoir.

It was estimated that some 20% of the radioactive products from the Chagan test escaped the blast zone, and were detected over Japan. This infuriated the USA for violating the provisions of the October 1963 Limited Test Ban Treaty, which banned atmospheric tests. 

Locals fish in the lake, despite warnings by authorities that it is hazardous.

Media
In Netflix's documentary series Dark Tourist (season 1 episode 4, "The Stans"), David Farrier visits and swims in Lake Chagan, and eats a fish from the lake, during his tour of Kazakhstan.

See also
 Sedan (nuclear test) – an American cratering detonation
 Pechora–Kama Canal – a proposed canal project involving nuclear excavation
 Lake Karachay – a natural lake highly contaminated by the dumping of high-level nuclear waste
 Volcanic crater lake – a body of water normally formed by volcanic or meteoric events

References

External links

Chagan
Chagan
Peaceful nuclear explosions
Explosion craters