An “’ominous” body of brown water was spotted seeping into the sea along the Borth coastline last weekend.

Authorities say the discoloured water is likely land run-off and not sewage overspill.

No discharges were recorded by Dwr Cymru/ Welsh Water during the weekend of 15th June or the prior week.

Natural Resources Wales (NRW) stated that upon investigation there was “some discoloured water entering the sea at Aberystwyth Harbour” but that it was passing.

Borth resident Dee Matthews captured the slick leaking into the blue Borth waters on Sunday morning: “NRW say that it isn’t sewage discharge yet the surfers say it is, either way, I don’t fancy swimming in the sea right now!

Borth resident Dee Matthews spotted the 'slick' off the Borth coast on the morning of 16th June
Borth resident Dee Matthews spotted the 'slick' off the Borth coast on the morning of 16th June (Dee Matthews )

“It moved across the water from south to north then it filled the sea and became one, it was very ominous to watch.

“My neighbour and I watched its slow progress across the bay.

“Last year there was an algae bloom that was smelly, this was not like that- what is it? Who’s testing the water? Can NRW be trusted?” NRW and Dwr Cymru stated it was “most likely caused by heavy rainfall in the Rheidol and Ystwyth catchments which resulted in increasing water levels early Sunday morning causing sediment to be pushed out into the bay.”

NRW issued a pollution warning over the same period for Aberystwyth South Beach due to the risk of reduced water quality from heavy rain.

‘Pollution Risk Warnings’ are issued for incidents including heavy rainfall which can cause faecal material to wash into the sea from livestock and storm overflow from urban drainage via rivers and streams. This comes as one swimmer suffered from “projectile vomiting” shortly after swimming in Borth on 14th June, with others also reporting nausea and sickness.

Despite Borth’s Blue Flag status for water quality, Across 2023 Dwr Cymru reported 43 spills in Borth, equating to 577 hours of overflow time.

Joe Wilkins, Ceredigion Community Engagement Officer at West Wales Rivers Trust, said: "Any suspected pollution events must be taken seriously.

“Recent events have highlighted the need to be aware of the types of pollution which can affect our rivers and seas.

“Accurate identification of the type of pollution, in addition to effective reporting, can ensure that everyone stays safe and the source can be dealt with.

“We offer training and support for spotting and reporting pollution through our Adopt a Tributary project so we encourage everybody in our catchment to get involved by emailing [email protected]."

Whilst Conservative Janet Finch-Saunders MS, Shadow Climate Change Minister, called for an “immediate full investigation”: “Wales has four times as many sewage discharges proportionately in Labour-run Wales than in England.

“The UK Conservative Government are holding water companies to task by subjecting polluters to unlimited penalties, while Labour let dumping continue without consequence in Wales.

“The Welsh Conservatives have long called for Labour and NRW to hold water firms to account and issue penalty fines.

“By allowing Dŵr Cymru to continue dumping unchecked, they are enabling the polluting of our waterways.”