An investigation has been launched in Denbighshire after a local stream turned milky white, sparking fears of pollution and potential harm to wildlife and children. The discolouration of Henllan Brook, which runs through residential areas and beneath Denbigh Friary and the town's retail park, was reported to Natural Resources Wales (NRW).
NRW has traced the source of the pollution to a culvert beneath a section of Denbigh town, but has yet to provide an explanation. A spokesman said: 'We are aware of reports of discolouration in a stream known as Henllan Brook in Denbigh and are currently investigating. Our officers have taken samples and we are awaiting the results of the analysis.' NRW has asked Denbighshire County Council to investigate further as the owner of the culvert.
The unusual sight was first noticed by residents on Monday, August 18. Speculation online ranged from white emulsion paint being dumped upstream to farmers spreading lime or dumping milk. Locals gathered their own samples, with one claiming that Dŵr Cymru Welsh Water was also involved in the inquiry.
After two days, the discoloration had begun to fade, leaving pools with a faint milky colour. Similar incidents have occurred across the UK in recent years, including a milk lorry crash in Carmarthenshire in 2021 and chalky white rivers in Devon in 2022. In May, watered-down paint was thought responsible for a River Wye tributary turning white in Hereford.
