Vemork Heavy Water Plant - 1942-44

In 1911, the Vemork hydroelectric station in Rjukan started exploiting the tremendous power in the waters that flow from the mighty Hardangervidda down into the narrow Vestfjord valley. Norsk Hydro, Norway´s great industrial adventure, was born here, among the perilous cliffs and deep gorges.

Late in 1938, Lise Meitner, Otto Hahn and Fritz Strassman discovered the phenomenon of atomic fission. Physicists everywhere realized that if chain reactions could be tamed, fission could lead to a promising new source of power. What was needed was a substance that could "moderate" the energy of neutrons emitted in radioactive decay, so that they could be captured by other fissionable nuclei. Heavy water was a prime candidate for the job.

Allied forces were determined to stop Nazi Germany from developing the atomic bomb. Of two materials to control a nuclear reaction -- pure graphite and heavy water -- the Germans chose heavy water because of a mathematical error in calculating the use of graphite. The German nuclear research community relied on a supply of deuterium oxide [heavy water] from the Norwegian Norsk Hydro plant, the only commercial production facility. This plant in Vemork, Norway was the world's major source of heavy water in the early 1940s. In the United States, Heavy water was used as a coolant and moderator in nuclear materials production reactors at the Savannah River Site.

Concentrating heavy water requires enormous amounts of electricity. In the 1930s, one of the few places in the world with power to spare was the Vemork plant of Norway's Norsk Hydro-Elektrisk, which had harnessed a 144-meter-high waterfall to produce fertilizers. The heavy water was generated as a by-product of producing fertilizer. Norsk Hydro supplied the world's scientific community with heavy water only as a sideline. In late 1939, the Germans began ordering heavy water in very large quantities, Norsk Hydro management suspected "some kind of deviltry."

With the cooperation of Norsk Hydro, the French managed to spirit the company's entire stock of heavy water, some 185 kilograms, out of the country under the noses of watchful German agents.

Germany captured Norway and the plant in May 1940. The Allies set out to destroy Vemork, a story familiar from the 1965 Hollywood film, Heroes of Telemark, starring Kirk Douglas and Richard Harris. The struggle for control of the heavy water plant took more than two years, involved four assaults and claimed 92 lives.

• On October 18, 1942, an advance party of four Norwegian SOE commandos -- Code-named "Grouse" -- were dropped in Norway on the Hardanger Plateau on a reconnaissance mission of the plant.
• In November 1942 the military campaign began with a disastrous British commando raid into Norway. Operation Freshman, mounted by Special Operations Executive (SOE), failed when thirty four Royal Engineers of the 1st British Airborne Division, together with the crews of two gliders and one bomber, died when their craft crashed into mountains during poor visibility. Survivors were interrogated, tortured, and executed by the Germans.
• On 28 February 1943 a second all-Norwegian commando raid -- Operation Gunnerside -- destroyed the Rjukan electrolysis plant, with the loss of 500kg of heavy water. The plant was, however, quickly repaired.
• On 16 November 1943 the American attempt to destroy the plant employed a total of 388 B-17 and B-24 bombers from Eighth Air Force. The raid resulted in considerable loss of civilian life but minimal damage the electrolysis building. While this attack did little damage it convinced the Germans to abandon the plant and move remaining stocks and critical components to Germany in 1944.
• On 20 February 1944 a final successful attack by saboteurs and members of the Norwegian resistance interdicted the remaining supply of heavy water by sinking the ferry D/F"HYDRO" taking a shipment to Germany.

The disassembled factory was later found in southern Germany during the closing stages of the war by members of Operation Alsos.