The UK water regulator, Ofwat, has proposed a £44.7 million enforcement package for Dŵr Cymru Welsh Water following an investigation into failures in the operation and maintenance of its wastewater assets.
The proposed action follows findings that the company breached its legal obligations in the management of its wastewater treatment works and sewer network. According to the regulator, Welsh Water did not adequately operate, maintain or upgrade its assets to ensure they could handle incoming sewage and wastewater flows. The investigation also identified shortcomings in governance, including insufficient oversight by senior management and the company’s Board to ensure infrastructure performance and regulatory compliance.
The case is the seventh in Ofwat’s sector-wide wastewater investigation, bringing the total value of proposed enforcement actions to more than £300 million
In a statement, Welsh Water said it accepts the findings of the investigation and acknowledged that improvements are required in its wastewater operations and oversight.
Under the proposal, the company has agreed to a £44.7 million redress package to be delivered during the 2025–2030 period. Ofwat stated that the funding will be absorbed by the company rather than passed on to customers through higher bills, and that the investment is additional to commitments already set out in the 2024 Price Review.
Welsh Water operates under a different financial model from other water companies in the UK. Its parent organisation, Glas Cymru, operates on a not-for-profit basis, meaning the company has no shareholders and typically reinvests profits in the business. The regulator said the enforcement package would be funded from these retained profits.
The package includes £40.6 million aimed at addressing environmental harm and reducing spills from specific storm overflows. The measures include investigations and sealing works on privately owned sections of the sewer network to limit groundwater infiltration, which has been identified as a significant contributor to frequent overflow events. A further £4.1 million will be allocated to improving river water quality in highly sensitive catchments.
Lynn Parker, Senior Director for Enforcement at Ofwat, said: “Our investigation has found serious and unacceptable breaches in how Dŵr Cymru Welsh Water has operated and maintained its sewage works and networks, which has resulted in excessive spills from storm overflows to the environment. We now expect them to focus on putting things right so that customers can regain trust in their water company and the critical service they provide.”
Welsh Water said the measures are in addition to their investment programme, with £4.2 billion planned between 2025 and 2030. According to the company, £2.5 billion of this funding is allocated to environmental improvements, including £889 million aimed at improving storm overflow performance.
A public consultation on the proposal is open until 2 April 2026 before Ofwat issues its final decision. The case is the seventh in Ofwat’s sector-wide wastewater investigation, bringing the total value of proposed enforcement actions to more than £300 million.
