VITE History Channel. Part 16. WW2. Norwegian Heavy Water Sabotage or German nuclear weapon project

  • Heroes of the Telemark
    Carry viking blood in veins
    Warriors of the northern land
    They live forever more

    Group photo of Norwegian commandos

    The Norwegian heavy water sabotage was a series of operations undertaken by Norwegian saboteurs during World War II to prevent the German nuclear weapon project from acquiring heavy water (deuterium oxide), which could have been used by the Germans to produce nuclear weapons.

    Heavy water made by Norsk Hydro

    In 1934, at Vemork, Norway, Norsk Hydro built the first commercial plant capable of producing heavy water as a byproduct of fertilizer production. It had a capacity of 12 tonnes per year. During World War II, the Allies decided to remove the heavy water supply and destroy the heavy water plant in order to inhibit the German development of nuclear weapons. Raids were aimed at the 60 MW Vemork power station at the Rjukan waterfall in Telemark, Norway.


    Prior to the German invasion of Norway on 9 April 1940, the Deuxième Bureau (French military intelligence) removed 185 kg (408 lb) of heavy water from the plant in Vemork in then-neutral Norway. The plant's managing director, Aubert, agreed to lend the heavy water to France for the duration of the war. The French transported it secretly to Oslo, on to Perth, Scotland, and then to France. The plant remained capable of producing heavy water. The Allies remained concerned that the occupation forces would use the facility to produce more heavy water for their weapons programme. Between 1940 and 1944, a sequence of sabotage actions, by the Norwegian resistance movement—as well as Allied bombing—ensured the destruction of the plant and the loss of the heavy water produced. These operations—codenamed Grouse, Freshman, and Gunnerside—finally managed to knock the plant out of production in early 1943.

    Vemork Hydroelectric Plant, 1935

    In Operation Grouse, the British Special Operations Executive (SOE) successfully placed four Norwegian nationals as an advance team in the region of the Hardanger Plateau above the plant in October 1942. The unsuccessful Operation Freshman was mounted the following month by British paratroopers; they were to rendezvous with the Norwegians of Operation Grouse and proceed to Vemork. This attempt failed when the military gliders crashed short of their destination, as did one of the tugs, a Handley Page Halifax bomber. The other Halifax returned to base, but all the other participants were killed in the crashes or captured, interrogated, and executed by the Gestapo.

    In February 1943, a team of SOE-trained Norwegian commandos succeeded in destroying the production facility with a second attempt, Operation Gunnerside, later evaluated by SOE as the most successful act of sabotage in all of World War II. These actions were followed by Allied bombing raids. The Germans elected to cease operation and remove the remaining heavy water to Germany, but Norwegian resistance forces sank the ferry carrying the water, SF Hydro, on Lake Tinn.

    Ferry carrying the heavy water, SF Hydro, on Lake Tinn

    Operation Gunnerside
    British authorities were aware the Grouse team was still operational, and decided to mount another operation in concert with them. By this time the original Grouse team was being referred to as Swallow. On the night of 16 February 1943, in Operation Gunnerside (named after the village where SOE head Sir Charles Hambro and his family used to shoot grouse), an additional six Norwegian commandos were dropped by parachute by a Halifax bomber of 138 Squadron from RAF Tempsford. They were successful in landing, and encountered the Swallow team after a few days of searching on cross country skis. The combined team made final preparations for their assault, which was to take place on the night of 27/28 February 1943.

    Supplies required by the commandos were dropped with them in special CLE containers. One of these was buried in the snow by a Norwegian patriot to hide it from the Germans; he later recovered it and in August 1976 handed it over to an officer of the British Army Air Corps, which was conducting exercises in the area. The container was brought back to England and was displayed in the Airborne Museum at Aldershot, later part of the Imperial War Museum Duxford.

    Following the failed Freshman attempt, the Germans put mines, floodlights, and additional guards around the plant. While the mines and lights remained in place, security of the actual plant had slackened somewhat over the winter months. However, the single 75 m (246 ft) bridge spanning the deep ravine, 200 m (660 ft) above the river Måna, was fully guarded.

    The force elected to descend into the ravine, ford the icy river and climb the steep hill on the far side. The winter river level was very low, and on the far side, where the ground levelled, they followed a single railway track straight into the plant area without encountering any guards. Even before Grouse landed in Norway, SOE had a Norwegian agent within the plant who supplied detailed plans and schedule information. The demolition party used this information to enter the main basement by a cable tunnel and through a window. Inside the plant the only person they came across was the Norwegian caretaker (Johansen), who was very willing to cooperate with them.

    The saboteurs then placed explosive charges on the heavy water electrolysis chambers, and attached a fuse allowing sufficient time for their escape. A Thompson submachine gun was purposely left behind to indicate that this was the work of British forces and not of the local resistance, in order to try to avoid reprisals. A bizarre episode ensued when fuses were about to be lit: the caretaker was worried about his spectacles which were lying somewhere in the room (during the war new glasses were nearly impossible to acquire). A frantic search for the caretaker's spectacles ensued; they were found, and the fuses lit. The explosive charges detonated, destroying the electrolysis chambers.

    The raid was considered successful. The entire inventory of heavy water produced during the German occupation, over 500 kg (1,102 lb), was destroyed along with equipment critical to operation of the electrolysis chambers. Although 3,000 German soldiers were dispatched to search the area for the commandos, all of them escaped; five of them skied 400 kilometres to Sweden, two proceeded to Oslo where they assisted Milorg, and four remained in the region for further work with the resistance.

    Great video content about Norwegian Heavy Water Sabotage
    Youtube Video

    Song «Saboteurs» about Norwegian commandos in Operation Gunnerside
    Youtube Video

    All for Victory! All for Vite!!!

Log in to reply