Norwegian Heavy Water Sabotage

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Norwegian Heavy Water Sabotage
Covert Operations

There was a race between Germany and the United States to develop an atomic weapon during the years leading up to and through World War II. Though the idea of nuclear fission was first mentioned in 1934, it wasn’t until 1938 that experiments confirmed it using uranium. One of the materials commonly used in the process of making an atomic weapon is heavy water: a form of water made using a particular isotope of hydrogen. It’s slightly denser than normal water and promotes fission in uranium. One method of producing heavy water is using electrolysis to separate it from regular water. This method requires electrolysis chambers and a lot of power. Germany’s heavy water supplier at the time was a hydroelectric plant run by Norsk Hydro in German-occupied Norway. To prevent Germany from continuing its atomic weapons research, British Special Operations Executive (SOE) began planning several operations aimed at limiting or destroying heavy water production at Norsk Hydro.

The first phase, codenamed Operation Grouse, involved four Norwegians parachuting onto a plateau near the Norsk Hydro plant. Their mission was to gather intelligence and blueprints concerning the plant and its heavy water operations. The Grouse team sent information back to SOE so the next phase could be planned. The second phase was codenamed Operation Freshman. A force of combat engineers and all the paratroopers of the British 1st Airborne Division were to be sent in by gliders to meet up with the Grouse team. Together, they were to blow up key parts of the Norsk Hydro plant. They were then to escape to Sweden.

Weather ended Operation Freshman almost before it began. One glider crashed into a mountain, killing all aboard. The other crash landed, killing most of its occupants. The survivors were captured by the Germans, tortured, interrogated, and murdered. The Germans were now aware of Allied interest in Norsk Hydro, and they improved their defenses. They installed a minefield around the plant, floodlights around the perimeter, and increased the number of guards. None of this deterred SOE. Four planners were deployed to search for other ways to send in commandos to link up with the Grouse team.

The next attempt, Operation Gunnerside, took place in February of 1943. Six more Norwegian commandos parachuted into Norway, and successfully joined the planners. They were to attack the plant together. Only one bridge spanned the river and ravine near the plant, and it was heavily guarded. To avoid the bridge, the teams climbed down the 656-foot-deep ravine, crossed the icy river, then scaled the other side, all without being detected. Inside the plant, the teams set explosives in the heavy water electrolysis chambers and left behind a British submachine gun. The idea was to fool the Germans into blaming the British, so locals wouldn’t be punished.

The explosives detonated after the teams escaped the plant. The blasts destroyed the heavy water electrolysis chambers and almost 120 gallons of heavy water. The Germans launched an extensive search for those responsible, but found no one. Though the operation was deemed a success, the Germans were able to repair the damage and restart heavy water production in 1943. Norwegian commandoes sabotaged this later production when the Nazis loaded the heavy water on a ferry for transport to Germany. A commando snuck aboard the ferry, placed explosives near the keel, and detonated them once he was off the boat.

Heavy Water Sabotage in Play

At your table, the role of the Operation Grouse team seems perfect for the PCs. They get to drop into Norway, conduct surveillance and reconnaissance of the plant, and survive the disastrous consequences of Operation Freshman. When finally infiltrating the plant, the NPCs from Operation Gunnerside can be heroically sacrificed as needed. Then everyone gets to escape the country. Later in the campaign, scuttling the ferry carrying the heavy water could be an entertaining callback to earlier exploits. Alter the challenges faced by the historical commandoes to fit your party’s strengths and weaknesses. Maybe a social PC has the opportunity to impersonate a guard. A particularly menacing party might have the chance to kidnap and intimidate a Nazi for information. Or the gal who always plays an impossibly rough-and-tumble PC could attack the bridge and distract the guards while the rest of the party sneaks into the facility.

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