Views rarely seen by the public. This is the inside of Derwent Dam. Beautiful crafted walls show the original untainted colour of the stone. The stone is dressed which is amazing considering that it would never be viewed, a nice touch of quality by the builders. There are two staircases in the cross tunnel leading each to the East and West Towers. The interior has a slightly eerie feel to it, monastic in a way. The temperature is constant and the slightly sandy floor gives the impression of the inside of a Pharoahs Tomb to an imaginative mind.
Not many people will know that the Dam stretches for hundreds of feet in to the hillside on both sides, which is one way to stop it sliding down the valley and losing all that water.
The interior of the Dam is made of stone “Plums”. Plum shaped boulders that were placed near to but not touching each other. When the concrete was poured in it filled the gaps and hence no air pockets of weakness.
A common misconception with the Dam is that it was used for target practice during the war. This is not true. The Dambuster Squadron did practice there as it was similar in design to the Mohne and Eider Dams. This fact combined with what seem to be pock mocks on the stonework developed into the myth of the RAF firing at the Dam for practice. The mundane truth about the pock marks is that they were made to accept the scissor lifting device used to place the large and heavy stones into place during construction.