In 1945, just 24 days before the end of World War II, the German submarine U-1206 was cruising off the coast of Aberdeenshire, Scotland, on its first voyage. The U-boat was cruising at a depth of 200 feet, and the crew were trying to repair the diesel engines. While the crew attempted to assess the problem with the diesel engines, it was soon discovered there was a leak, and poisonous gas and water were filling the submarine.
The leak was coming from an unusual source, the submarine’s toilet. The toilet system on this particular U-boat had been designed with an intricate high-pressure valve system so the submarine could dive deeper and wouldn’t have to expel waste closer to the surface. This allowed the submarine to stay away from enemy attacks.
The captain, 27-year-old Karl-Adolf Schlitt, had been using the toilet and had difficulty flushing it correctly. He summoned an engineer to help, but the engineer opened the wrong valve. Instead of the wastewater going out into the ocean, the water from the toilet came back in the vessel. The incoming water and sewage flooded the submarine’s batteries, which were located beneath the toilet. This caused the batteries to release deadly chlorine gas. There was no option other than to take the submarine to the surface, ten miles off the Scottish coast.
When the submarine got to the surface, the crew began to blow clean air into the vessel to rid it of the deadly chlorine gas. But it was too late. The U-boat was spotted by a British patrol and was attacked. Schlitt ordered the crew to abandon the ship, and he scuttled the submarine, sending it to the bottom of the ocean. One man was killed during the attack, and three men drowned after abandoning the submarine. The remaining 46 crew members were captured by the British.
The wreck was located in the mid-1970s when a crew laying an underwater oil pipeline discovered it at the bottom of the ocean at a depth of 230 feet.