Overview

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Natural Resources Wales (NRW) is responding to ongoing pollution incidents linked to infrastructure at the Marlas Sewage Pumping Station (SPS) near North Cornelly in Bridgend, which are impacting the River Kenfig.

We are taking this matter extremely seriously. The scale of environmental impact on the River Kenfig is unacceptable, and we fully recognise the concern and frustration this has caused for local communities, as well as the damage to wildlife and the wider environment, including Kenfig National Nature Reserve.

This page will be updated regularly to provide the latest information about what is happening and the action being taken.

Background

Marlas SPS and its associated rising main, which spans 9km and is used to convey sewage to Afan Wastewater Treatment Works, are operated by Dŵr Cymru Welsh Water (DCWW).

Marlas SPS has a water quality discharge permit (number BP0169901), which permits a discharge from the pumping station subject to Condition 2 of the permit. This permit allows the discharge of storm sewage or discharge of sewage in an emergency, both within specific criteria.  

DCWW has been experiencing reoccurring bursts along the Marlas rising main since August 2023. We have been responding and monitoring these bursts along with regulating the Marlas SPS environmental permit.

During February 2026, the situation escalated with a continuous discharge from the Marlas SPS. As a result, DCWW commissioned a temporary sewage treatment plant at Marlas SPS.

These issues have led to ongoing discharges to the River Kenfig. Following the installation of a temporary over land rising main on Tuesday 9 June 2026, the continuous discharge from Marlas SPS and the temporary sewage treatment plant has ceased.

What is being done

The ongoing discharge has had a significant impact on the River Kenfig downstream, including visible pollution and odour.

We are taking this matter extremely seriously and are continuing to respond, monitor and investigate the ongoing incidents linked to Marlas SPS. We have undertaken regular site visits to the affected area.

DCWW, as the operator, is responsible for complying with the conditions of its environmental permit and managing and mitigating impacts of the on-going discharge.

As the regulator, we are undertaking detailed formal investigations and assessing the environmental impact. We will take the appropriate action in line with our Enforcement and Sanctions Policy.

During our formal investigations we are unable to provide detailed information as disclosure of investigative details at this stage could risk prejudicing any enforcement outcome.

We have informed DCWW that we expect them to undertake remedial work to clean up affected stretches of the River Kenfig along with a plan for longer term enhancement of the river and its biodiversity.  

Latest information

We will provide the latest updates in this section.