In World War II, the dam was as part of Operation Chastise, destroyed by special bouncing bombs dropped by British Lancaster bombers of No. 617 Squadron RAF in the early morning of May 17 1943, creating massive destruction and loss of life downstream. Through the breach in the dam, 70 meters wide and 22 meters deep, water emptied at the rate of 8,000 m³ per second into the narrow valley below, a total of about 160 million m³. A flood wave of 6-8 meters in height roared through the river valley as far as 30 km downstream, before it diminished in the widening floodplains of the lower Eder, the Fulda and the Weser. About 70 people perished (some non-German sources erroneously cite an early total of 749 for all foreigners perished in all POW and labour camps downriver of the Möhne dam as the casualty at supposed POW or labour camp just below the Eder Dam.)
The dam was rebuilt within months by forced labor drawn from the construction of the Atlantic Wall under the command of Organisation Todt, and the lake today is a major summertime recreational facility. Its capacity of 199.3 million m³ makes it the third largest reservoir in Germany.
At low water, in late summers of dry years, the remnants of three villages (Asel, Bringhausen, and Berich), along with a bridge across the original river bed, that were submerged when the lake was filled in 1914, can be seen, and descendants of people buried in the now submerged cemeteries go to visit the graves of their ancestors.
In the popular PC First-Person Shooter Call of Duty, the dam is rebuilt and the player, a British Special Forces agent, must sabotage AA guns on the dam during the summer of 1944. This, however, is highly fictional, because the dam was never attacked after 1943. Germany was already weakened after the first attack in 1943, and to the Allies, there were other, more important bombing campaigns to be carried out. It also returns in Call of Duty 3 as a multiplayer map.