Dead fish found after thick foam fills river

News imageEnvironment Agency Thick white foam on the surface of the River Thet at Thetford. On the far side is a river bank with trees; in the middle branches with autumnal leaves meet the water; on the right is a glimpse of a bridge balustrade top. Environment Agency
The thick foam was found on the River Thet on Saturday

Dead fish have been found on a river where thick white foam appeared, the Environment Agency has said.

The substance was seen on the waterway along the River Thet in the centre of Thetford, Norfolk, on Saturday.

A spokesperson for the Environment Agency said: "Our officers have seen small dead fish and fry. This is obviously upsetting."

They said it was investigating the incident, adding that "the pollutant is an unknown substance".

News imageRichard Knights/BBC A small layer of white foam was on a river. There was a hedge which ran alongside the edge of the river.Richard Knights/BBC
The foam had started to subside on Sunday
News imageRichard Knights/BBC A grey stone bricked bridge was going over a small river. On the right was green algae and on the left, near the bridge, was white foam.Richard Knights/BBC
The foam was found along the River Thet in the centre of Thetford on Saturday

The Environment Agency said it had been on site to take samples from the river.

A spokesperson said: "We have detected the source and expect the foaming to reduce naturally as it is diluted by the rain that will increase the flow of the river over the next few days."

The source has not been revealed.

Firefighters also attended and Norfolk Fire Service warned people not to enter the water or allow their pets to swim in or drink from the river.

An Anglian Water spokeswoman said checks confirmed the foam had been caused "by a third-party" and was not from any of "our equipment or assets in the area".

News imageRichard Knights/BBC Brian Holt was standing on the left of an image looking towards the camera with a light smile. He was wearing a black and white stripped jumper and beige coat, and was stood in front of a river.Richard Knights/BBC
Brian Holt, a local angler, said he saw the foam forming in the river in Thetford

Brian Holt, 65, a local angler, said: "It looked like someone had put loads of Fairy Liquid in the water because it was white foam and was just getting worse."

Mr Holt said he saw "foam everywhere coming down the river" when fishing.

He said he usually fished in the area every other weekend and saw "fish floating" in the water.

News imageRichard Knights/BBC A small gathering of thick white foam was on top of a river. There was a green bush on the right which was standing above the water.Richard Knights/BBC
The Environment Agency said it was investigating the cause of the foam

A spokesperson for the Environment Agency said: "We will survey the impacts once the pollutant has gone to assess longer-term impacts."

They added that its officers had attended an incident involving foam on the River Thet on 23 December 2024 but were unable to identify the source on that occasion.

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