Burst on the Marlas rising main

What’s happened?

On 30 April, we declared a Gold Incident after a significant burst on the Marlas rising main. The condition of the pipe worsened much faster than expected, leading to discharges impacting the River Kenfig. Our first response involved using tankers to remove wastewater from the network and reduce pressure on the system. While this helped manage the immediate problem, it was only a temporary measure.

What are we doing now?

We’ve now installed a temporary wastewater treatment process at Marlas Sewage Pumping Station (SPS). This allows wastewater to be treated on site instead of being removed by tanker.

The treatment process uses naturally occurring bacteria to break down waste in the water. These bacteria need time to build up and become fully effective, so improvements happen gradually over time.

This means:

• The treatment process becomes more effective each day
• Water quality improvements will happen progressively
• Our teams are monitoring and adjusting the system daily

We are working as quickly as possible to improve the quality of water being returned to the environment.

Supporting the health of the river

Over the weekend we started aeration work in the River Kenfig.

Aeration adds oxygen into the water to help support fish and other wildlife, improve river health and reduce unpleasant odours. We’ll continue monitoring the river closely to make sure this work is having the right effect.

Further protection measures

We’re also installing around 4.9km of temporary overland pipework to further reduce the risk of future discharges.

This is a complex project because the route crosses several areas of privately owned and environmentally sensitive land, so the work will take time. At the moment, we expect this to take around six weeks to complete.

Once this temporary pipework is in place, the temporary treatment works at Marlas SPS will be removed.

Our long-term solution

To address the root cause of the issue, we’re investing £13 million to replace 4.5km of the existing sewer main across the Kenfig and Port Talbot area.

This investment will help to:

• Improve the resilience of the network
• Reduce the risk of future failures
• Better protect the local environment for the long term

We currently expect this replacement work to be completed by January 2027.

Keeping you updated

We’ve been sharing updates with customers, local groups and stakeholders through newsletters, social media and video updates, and we’ll continue to provide regular information as work progresses.

We understand how worrying this situation is for local people and we’re sorry for the disruption and environmental impact it has caused. Our teams are working around the clock to improve the situation and deliver a long-term solution for the community and the river.

You can stay up to date with our progress on site by visiting In Your Area.