Welsh Water, also known as Dwr Cymru, has submitted planning applications for its £600 million Cwm Taf Water Supply Strategy, described as the largest water-infrastructure project in the company’s history. The scheme aims to secure a safe and reliable drinking-water supply for more than 400,000 properties across South Wales. It is intended to strengthen the region’s water network for future generations.

The project comes at a time when Welsh Water says climate change is placing growing pressure on its infrastructure. More frequent storms, heatwaves and changing weather patterns are affecting the availability and quality of raw water sources. At the same time, several existing treatment assets are ageing and need modernisation to continue delivering dependable services.

Under the proposed plans, Welsh Water will build a new water-treatment works and a new pumping station at the existing Pontsticill site. The company will also construct new pipelines to connect these facilities with the existing water-supply network. In addition, the Llwyn-onn Water Treatment Works will be upgraded as part of the wider strategy.

Once the new facilities are operational, Welsh Water plans to decommission the existing treatment works at Pontsticill and Cantref. These sites have served the region for more than a century and are beginning to show their age. Replacing them with modern infrastructure is expected to improve resilience, reduce operational risks and support a more secure drinking-water supply.

Welsh Water chief executive Roch Cheroux described the investment as one of the most significant in the company’s infrastructure for generations. He said the project would provide customers with a safe, reliable and sustainable drinking-water supply for decades to come, while helping the utility respond to the challenges posed by climate change.