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Public outcry against emptying of Rhondda reservoir

13 Apr 2024 4 minute read
Clydach Reservoir In Rct. Picture From Google Maps

Anthony Lewis, local democracy reporter

Hundreds of people have signed a petition against the emptying of a reservoir in the Rhondda.

There was a public outcry recently when the Clydach Reservoir in Llanwonno Forest was drained “with no warning to the public” with people saying it now looks an “absolute mess”.

Dŵr Cymru/Welsh Water said it intended to turn the reservoir back into a natural lake as it has not been used to supply drinking water since 2004.

It added it had started to drain the reservoir as part of its planning for the work and said it was “sorry” for any “confusion locally”.

The petition, set up, by Jake Castle and signed by more than 400 people, said it is “an act of social and environmental vandalism” and that the loss of the reservoir would devastate local people.

He has called on the CEO of Dŵr Cymru/Welsh Water to immediately re-think its plans and find alternative options.

Oasis of calm

The petition said: “Over many decades the Clydach reservoir has become an incredibly important place for the surrounding communities of Ynysybwl, Pontypridd, Cwmaman, Ferndale, Perthcelyn, and Mountain Ash.

In an area short of high-quality and accessible destinations it forms the end point for family walks, hikes, rambles, cycle trips, and runs.

“Not only does it help improve the physical health of local people, in an area blighted by high rates of diabetes and obesity, but it has a hugely positive benefit on our mental health and wellbeing. This was clear during the Covid lockdowns when it became an essential oasis of calm, helping to ease our anxieties.

“Climate change predictions show that extreme rainfall will become more common in Wales in the coming years. Ynysybwl and Pontpridd have already suffered devastating floods in 2020.

“The reservoir could be used to manage flood risk by storing and slowly releasing flood water, lowering the peak flows of the Clydach and Taff rivers. Heatwaves, droughts, and forest fires will also become more common in summer.

“Already the reservoir is used by helicopters to fill up buckets when fighting fires locally. The loss of the reservoir would therefore increase the risk of forest fires spreading, destroying habitat and private properly and putting lives at threat.”

Well-established habitat

“The removal of the reservoir would contradict the local priorities of Natural Resources Wales to slow water from the uplands and fight wildfires. The Clydach reservoir forms an important, locally rare, and well-established habitat for many animals and birds.

“The reservoir supports insect life which sustains herons, ducks, kingfishers, swallows, swifts, cuckoos, night jars, and wagtails. Rare birds of prey, including goshawks, sparrow hawks and merlins, live nearby. If the reservoir hadn’t recently been drained (without any consultation) Canada geese would now have returned and be nesting there.

“Amazingly otters have also been recently spotted in the Clydach river below. Considering this the recent statement issued by Dŵr Cymru to the Ynysybwl Regeneration Partnership, which claimed the removal of the reservoir would ‘restore’ and ‘re-naturalise’ the water course, is misleading and disingenuous. There is already a thriving ecosystem there which would be destroyed by the removal of the reservoir.

“As members of the surrounding communities we demand Dŵr Cymru finds workable alternatives to these devastating plans. Indeed, failure to do so would completely contradict your own stated ambitions to align with the seven well-being goals in the Future Generations Act.”


Dŵr Cymru/Welsh Water said: “We are aware of the petition and are still working on our plans, which will be shared with the community in coming weeks.

“Clydach Reservoir has not been used to supply drinking water since 2004 and will not be needed again.

“We therefore are looking at how we can safely turn the reservoir back into a natural state – just as it was before the dam was constructed.  This will ensure the site will be safe and available for the local community to enjoy for years to come.

“While there has been no formal public access to the site, we are looking to make a formal right of way to give people better access to the site in future if possible.

“To help us with the planning for the work, we have started to drain the reservoir, which we appreciate may have caused some confusion locally, and for which we’re sorry.

“Protecting the wildlife onsite is a priority for us and we engaged with Natural Resources Wales before we commenced draining the reservoir. We will continue to engage with NRW and other wildlife bodies as we develop the plans for the work.”

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Mab Meirion
Mab Meirion
1 month ago

That was a big fire bucket they just emptied there…joined up thinking doesn’t fit on a job sheet…or the feelings of the local people…

Mab Meirion
Mab Meirion
1 month ago
Reply to  Mab Meirion

There is a photo on BBC Cymru of the sad mess they have made of an entire eco-system, dumb vandals!

JJ Jilliams
JJ Jilliams
1 month ago

Are the community going to pay for the maintenance and safe keeping of the dam? Are they going to pay for the engineers to provide supervision and inspection. Are they going to pay for continual monitoring and record keeping?

1 month ago
Reply to  JJ Jilliams

What upkeep is there on a dam that’s got an earth and stone embankment? This isn’t Hoover dam but a large lake with a spillway. As for the cost, if we are paying water bills that is where it’s coming from surely, plus if the value is the bottom line to you we can factor in the use by helicopters and charge them can’t we? The reality is they drained a lake to make a lake, and will aim to remove infrastructure which will be expensive replace, handy to keep around as insurance against droughts or to send to England… Read more »

JJ Jilliams
JJ Jilliams
1 month ago
Reply to  Samson

They’re not draining a lake. They’re decommissioning a reservoir and are planning to return the watercourse and body to it’s original state. Maintaining the reservoir for aesthetic purposes makes no economic sense for a reservoir owner or the local community. Decommissioning it to remove any potential flood hazard does make sense, however. If it remains, the owners will need to ensure the safety and integrity of the reservoir and it’s dam. It’s a very expensive upkeep and doesnt have to be the Hoover dam to be a flood risk to the community. The reservoir is high risk in terms of… Read more »

1 month ago

Tricky. Dams are being removed across the globe and habitats returned to what they were and ecological systems are being improved. Dams also cause many issues.
Be interesting ti see what happens here.

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