![[ image: width=150]](/olmedia/50000/images/_54811_tanks_150.jpg)
![image: [ Giant water tanks are now being demolished ]](/olmedia/50000/images/_54811_destruction_300.jpg)
The tanks, built before the First World War, were originally used to help design ships.
In the summer of 1942, however, they were put to different use when Barnes Wallis and his team spent months firing two-inch diameter balls from a catapult across the water.
They were trying to work out the perfect speed and height from which to drop the bouncing bombs for maximum range and accuracy. One of the scientists on the project who has been back to the site, Herbert Jeffree, recalls that their first attempt was less than successful when the ball bounced off to the side rather than towards the target.
Eventually the experiments proved successful, convincing the RAF of their worth and on May 16, 1943, the newly-formed 617 Squadron took off, led by Wing Commander Guy Gibson.
Its first and defining mission, immortalised in The Dam Busters film, was to bomb German dams in an attempt to destroy important military factories by flooding them.
![[ image: width=150]](/olmedia/50000/images/_54811_engineer_150.jpg)
The targets were the Moehne, Eder and Sorpe dams in the Rhineland. They generated hydroelectric power to keep the industrial heart of Germany beating.
The Moehne and Eder dams were successfully breached but at the cost of nearly half the squadron. And, although seen at the time as a heroic triumph, there was little significant material damage to Germany's war effort.
But, another of the bouncing bomb scientists, Norman Boorer, says that this ignores the psychological effect of the raid. He argues that the Germans were given a kick in the teeth.
The water tanks are currently administered by the National Physical Laboratory, the organisation responsible for holding British standards for measurements such as distance, mass, light speed and time.
The NPL's role is to define these constants with ever-increasing accuracy, not to preserve historical monuments. Another factor is that ships are now designed using computers rather than water tanks.
The plan is to replace the tanks with a park. English Heritage has recommended that one of them should be turned into a pond but a more likely memorial is a plaque.
Dambusters history
Internet Movie Database - The Dam Busters
National Physical Laboratory
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