Although we have visited Elan Valley many times we had never been to the top of the Claerwen (Clear Light) dam.

Built between 1946 – 1952 by a workforce of almost five hundred men the outside of dam blends in with the other Elan Valley dams, although the inside is a concrete structure. Because British stonemasons were working in London after World War II Italian stonemasons were employed to work on the dressing stones,

Claerwen was opened by Queen Elizabeth II on the 23rd of October 1952 on her first engagement in Wales.

At eighteen metres deep Claerwen holds almost as much water as all the other reservoirs combined.

There is potential for producing renewable electricity from the one hundred and ninety-nine million tonnes of water stored in the reservoirs. Since 1997 there has been hydropower production from turbines installed at the base of all the dams. Clearwen can produce 1680 kilowatts. Combined all the dams can produce 3.5 megawatts, which is about six thousand homes.

The day before we were here it was a gloriously sunny day and we’d driven and walked a little way around the four dams on the river Elan: Craig Goch, Pen y Garreg, Garreg Ddu, and Caban Coch.

The following day it rained. But the photographer was adamant it would clear up (he’s an avid follower of the BBC weather forecast!), and, by the time we’d driven to the top Claerwen dam he was insistant there would be a break in the drizzle.

As usual he was right.

Next time we will walk to the Dol y Mynach dam. Dol y Mynach is the unfinished dam and is a Site of Special Scientific Interest (SSSI. There is a bird hide here from which Ospreys and other species of birds, including the Crested Grebe, have been spotted.

The late nineteenth century plan for the collection of dams and reservoirs in the Elan and Claerwen valleys included three dams on the River Claerwen. These would be constructed later when additional water supplies were needed.

Image courtesy of : https://tinyurl.com/8feekf7p

So it was necessary to build the base of the Dol y Mynach Dam at the same time as the other dams in the adjacent valley of the River Elan. Dol y Mynach’s foundations were built during the first phase of the scheme, and was planned to be completed in the second phase, alongside plans for two other dams in the Claerwen valley. But after World War II, technology had advanced so the only the much larger Claerwen needed to be built. But, just in case it’s needed, a tunnel runs from Dol y Mynach to Garreg Ddu reservoir to fill up Garreg Ddu.