It was built to stave off possible catastrophic flooding should the upstream Imnam Dam in North Korea collapse, either intentionally or by accident.

The Bukhan River is a tributary of the Han River, and catastrophic scenarios foresaw a flood engulfing the South Korean capital of Seoul in case of an attack by North Korea.

Construction was halted before completion, amidst allegations that the threat had been grossly exaggerated.

Construction resumed after satellite photographs in 2002 revealed the existence of cracks in the Imnam Dam, triggering fears that it could collapse in case of heavy rains.

[4] In September 2005, North Korea released massive quantities of water without warning, causing serious flooding just south of the border.