Swansea Marina was covered in a yellow foam over the weekend leading many to worry about pollution
14:16, 25 Aug 2025Updated 14:16, 25 Aug 2025
This yellow discharge in the Swansea Marina was first reported on August 23 and remained at least for a day
Visitors to Swansea Marina were shocked to find a thick yellow foam covering the River Tawe just underneath the city’s Trafalgar Bridge over the weekend. Speculation was rife on social media about the nature of the foam and whether it was due to a sewage discharge.
Welsh Water has now clarified this was not a result of sewage pollution as they do not have a storm overflow in Swansea Marina. Instead the firm suggested the discharge could have been caused from other sources like highway drains or waste from boats.
The foam remained for at least a day and was visible until Sunday, August 24.
Welsh Water have confirmed it was not related to sewage pollution
A spokesman for Welsh Water said: “We are aware of yellow foam reported at Swansea Marina over the weekend.” Never miss a Swansea story by signing up to our newsletter here.
They added: “This is not as a result of a sewage pollution as we do not have a storm overflow in Swansea Marina.
Locals had been left perplexed and worried about river pollution upon seeing the discharge
“There are a number of other reasons for a discharge of this nature including highway drains, waste from boats etc, and particularly during warmer weather you can expect to see a lot more algal activity.”