'Overwhelming stench of sewage' as Welsh river hit by ongoing spill
Major infrastructure failings have prompted urgent calls for action as pollution continues to threaten wildlife almost two weeks after the spill was first reported
Calls are mounting for urgent action to be taken after a major sewage spill left parts of a Welsh river polluted, with residents warning the once-thriving waterway has become "devoid of life". Welsh Water has since confirmed that a key sewer pipe failed "decades ahead of its expected lifespan," prompting round-the-clock work.
The Afon Kenfig, which runs along the border of Bridgend and Neath Port Talbot near the Kenfig Nature Reserve, remains under scrutiny as concerns grow over the continuing impact on wildlife, conservation efforts and local communities.
The spillage was first reported on May 15 but little progress appears to have been made in tackling the problem, with photographs from the scene showing sections of the river murky and almost milky in colour while the smell of sewage has been described as "overwhelming". For our free daily briefing on the biggest issues facing the nation sign up to the Wales Matters newsletter here.
Welsh Water has said that around 45 workers are operating day and night to contain the damage, while temporary repair work is not expected to be operational until mid-June.
Senedd Member Sera Evans MS, who represents Afan Ogwr Rhondda, called on Welsh Water to "act urgently" over the ongoing pollution this week, saying "the impact on local residents, wildlife and conservation is devastating and cannot be allowed to continue."
Ms Evans visited several locations along the river with colleagues Alun Cox MS and Elyn Stephens MS. While there they met residents and representatives from environmental charity A Peace for Nature to assess the scale of the damage first-hand.
Locals specifically flagged the smell in the area, health and safety issues and concern for wildlife, which has been severely impacted by the pollution in the river.
Describing the conditions she witnessed, Ms Evans said the scale of the pollution was difficult to fully convey in photographs alone.
"I visited several sites along the river with my colleagues Alun Cox MS and Elyn Stephens MS, where we met with local residents and representatives from A Peace for Nature to see first-hand the scale of the damage being caused," she said.
"It is imperative that immediate action is taken to reduce the impact of the pollution, prevent any further deterioration of the river, and protect this important natural environment for the future."
She added that pressure would continue to be placed on Welsh Water until action is taken.
"We will continue pressing Dwr Cymru / Welsh Water to ensure effective measures are put in place as a matter of urgency," Ms Evans said. "The photos simply do not capture the true scale of the damage to the river or the overwhelming stench of sewage."
During a recent visit to the Afon Kenfig, WalesOnline witnessed the strong odour near one stretch of the river close to the nature reserve, a popular destination for walkers and nature lovers.
Local fisherman Stuart Mears said the environmental damage has been "devastating". "All the fish and invertebrates have died from the pumping station downwards and a lot of the bank-side creatures have left the area as well," he said.
"This has affected around two to three miles of the river down to the sea. Local people are up in arms about it because those who use the Kenfig Nature Reserve can't go near the river now."
In light of this, a Welsh Water spokesperson said: "We are very sorry for the impact we are having on the environment following the escalated deterioration of our sewer main that runs between Kenfig and the Port Talbot area.
"We are taking this very seriously, with around 45 people working day and night on a multi-faceted strategy to minimise the impact and bring the issue to a close as quickly as possible.
"Following a number of bursts over the past couple of years, work commenced last year on a £13m project to replace 6km of the main to protect the local environment.
"Unfortunately, the pipe failed completely - decades ahead of its expected lifespan - so we began managing flows with tankers while we installed a full wastewater treatment process at Marlas Sewage Pumping Station. We are continuing to closely monitor its performance.
"In addition, we have deployed specialist aeration equipment at multiple points along the river, specifically intended to improve water quality and support the recovery of the ecosystem.
"Due to the hot weather conditions over the weekend and throughout this week, we have now introduced tankering from Coed Hirwaun Pumping Station and Ton Kenfig Pumping Station. During hot weather, flows decrease and we see a concentration in sewage strength. It also reduces in volume, which is allowing us to tanker more away to Afan Wastewater Treatment Works, to support the temporary works in Marlas.
"In the meantime, we are continuing to lay the last few hundred metres of temporary overland pipe before we can pressure test it and bring it into operation. We expect this to take place by 16th June 2026, however we are working hard to bring this date forward.
"We understand the concern surrounding this incident and would like to apologise again for the impact we are having."