Caustic soda from Diageo's Cardhu reached a tributary of the River Spey; Scotland's environment agency is investigating and the company has apologized
Diageo, the world's largest spirits company, is under investigation by Scotland's environment agency (SEPA) over a chemical spill that killed fish and other wildlife in the Knockando Burn, a stream that flows into the River Spey, in the heart of whisky country. According to Bloomberg, the substance came from the Cardhu distillery, one of the four main producers of whisky for Johnnie Walker; Diageo confirmed to Just Drinks that the case involves Cardhu.
The spill took place in late April, according to Bloomberg, and was reported by the British press in May. The substance, believed to be caustic soda, is used to clean stills and pipes. According to people familiar with the matter who spoke to Bloomberg, a valve was inadvertently left open, and the chemical flowed straight into the water.
The estimate cited by Bloomberg is up to 3,000 creatures killed along more than a mile of the stream, including salmon, trout, eels, invertebrates and frogs. The Knockando Burn is a spawning tributary. Duncan Ferguson, director of the Spey Fishery Board, told the PA news agency that a 2 km stretch was destroyed and could take years to recover, and that it is one of the biggest incidents he has seen in more than three decades on the river. Fisheries experts who spoke to Bloomberg say fish stocks could take more than 20 years to return to previous levels.
SEPA says its inquiry is ongoing and that it does not comment on evidence. At the end, it may take enforcement action and, if a potential offence is found, refer the case to Scotland's prosecution service, which decides whether to prosecute. According to Bloomberg, fines for companies can reach £40,000.
We are sincerely sorry for the damage caused to the local environmentDiageo spokesperson, to PA
The company says it has updated its controls, is cooperating with SEPA and is discussing a long-term plan to restore the area. Scotch accounted for 24% of Diageo's net sales in fiscal 2026, and the company has 31 distilleries in Scotland, according to Just Drinks.
Bebidário's catalog includes labels from the family that uses Cardhu whisky, such as Johnnie Walker Red Label, Black Label and Gold Label Reserve.
Sources: Bloomberg (October 19, 2026), Just Drinks (October 20, 2026), PA Media (October 20, 2026).
