Cwm Taf Water Supply Strategy


Thank you for visiting our page for our plans to future-proof our supply of water to our customers across Merthyr Tydfil and the surrounding areas. Our vision, which includes a new and resilient water treatment works, will serve our customers with fresh, clean drinking water for decades to come.

We are developing a plan to build new water treatment works and associated facilities, to replace our existing works at Llwyn Onn, Cantref and Pontsticill which are nearing the end of their operational lives. This makes them more challenging and costly to operate, which is why a new, innovative solution is required so that water supplies to customers are protected into the future.

The new facilities will not only provide new and improved water treatment processes but will also provide enough water storage to cater for future population growth and also make it more resilient to the effects of climate change.

The project will ensure we continue to provide a first-class supply to customers every time they open their taps.

Our emerging proposals

Our emerging proposals include:–

  • New water treatment works facilities near Merthyr Tydfil.
  • New raw water pipelines to carry water from existing reservoirs in the Brecon Beacons National Park to the new water treatment works.
  • New treated water pipelines to carry treated water from the new water treatment works to the existing network and on to customers.
  • New and upgraded pumping stations to boost water pressures and ensure water can reach our customers.

The new facilities are necessary to provide:

  • New and improved water treatment processes to provide consistently high-quality water.
  • Additional water storage capacity to ensure we have a reliable supply.
  • Future proofed facilities to cater for population growth and to be resilient to effects of climate change.

Protecting the Environment

We take our responsibility for protecting the environment seriously and that is why we have been carrying out a number of surveys to ensure the project, if given the go ahead, has the least impact possible on the local environment. These surveys include ecological and archaeological ones so that we fully understand the characteristics of the areas proposed for the work.

We’re also taking great care to ensure that our plans minimise the impact on the local environment, including considering the visual appearance of how the buildings look and sit within the landscape.

What’s happening now?

We held a six week non-statutory consultation period to introduce our early thoughts and design ideas to the local community. The consultation period ran from 28th February 2022 to 8th April 2022 and included us holding information events in the local community. We also launched a virtual exhibition room and this can still be viewed here.

During our non-statutory consultation period, we asked people to provide us with feedback on our initial plans and we would like to thank those that took the opportunity to do so. The feedback received was extremely useful, and since we held the non-statutory consultation, we have been reviewing the feedback to ensure that where possible this informs and shapes our plans.

We had originally stated that we wanted to submit our application towards the end of 2022. However, we have decided to take some extra time to ensure full consideration is given to balance the local community’s feedback together with our need to build new water infrastructure before our plans are finalised.

In March 2023, we sent an update letter to customers in the Merthyr Tydfil area to explain where we are with our plans and when we anticipate we will have further information to share. A copy of the letter can be viewed here.

Following our non-statutory consultation, we produced a Frequently Asked Questions document which answers the most common questions people asked us. Here is a link to the document which we hope you find useful to better understand our plans.

Should you have any queries in the meantime then please email us cwmtafproject@dwrcymru.com to get in touch.