History (plagiarised from Wikipedia)
Ladybower Reservoir is a large Y-shaped reservoir, the lowest of three in the Upper Derwent Valley in Derbyshire, England.
It was built between 1935 and 1943 by Derwent Valley Waterboard to supplement the other two reservoirs in supplying the water needs of the East Midlands. It took a further two years to fill (1945). The dam wall was built by Richard Baillie and Sons, a Scottish company.
The dam's design is unusual in having two totally enclosed bellmouth overflows (locally named the "plugholes") at the side of the wall. These are stone and of 80 feet (24 m) diameter with outlets of 15 feet (4.6 m) diameter. Each discharges via its own valve house at the base of the dam. The overflows originally had walkways around them but they were dismantled many years ago. The bell mouths are often completely out of the water and are only rarely submerged, often after heavy rainfall or flooding. Here’s a pic of one of the plugholes being built...
The building of the reservoir resulted in the 'drowning' of the villages of Ashopton and Derwent (including Derwent Woodlands church and Derwent Hall). Ashopton stood roughly where the road to the Snake Pass met the Snake valley. The buildings in Ashopton were demolished before the reservoir was filled, but much of the structure of Derwent village was still visible during a dry summer some 14 years later. The narrow stone Packhorse Bridge over the Derwent was removed and rebuilt at the head of the Howden reservoir. The clock tower of the church had been left standing and the upper part of it was visible above the water level until 1947.
However, the drought of 1947 meant that the exposed church ruins were drawing large crowds of umbexers, hoping to get GoPro content of the ‘forgotten submerged city’ for their YouTube channels and the remains were therefore fully destroyed in December that year, spoiling the fun for everyone else. (Nothing changes, eh?)
The visit
Having planned to do something else but realising we wouldn’t have enough time, me and @Esoteric Eric diverted here to explore one of the plugholes that we had held in reserve for just such a time. As you can see in this pic, the water levels were quite high but with no rain forecast we decided we’d be ok for a quick look inside one of the plugholes.
These things are ENORMOUS. The echo inside is amazing...
The whole time we were inside the tunnel we could hear the amplified sound of water lapping at the edge of the massive overflows.
Looking in...
Looking back...
Looking up towards the plughole. At this point the lapping of the water at the other end has become more of an amplified roar...
And for scale...
And GTFO...
