River group calls for legal action over foam

A thick foam was seen covering parts of the River Thet on Saturday

A river preservation group is calling for legal action against those responsible for thick white foam pollution for the second time in a year.

The substance filled a stretch of the River Thet in Thetford, Norfolk, on Saturday - and dead fish could be seen.

Roseanne Gough of the Thetford River Group - which carries out monitoring of the waterway, including litter trawls and water quality testing - said the latest incident was "devastating for the community and the wildlife as well".

The river is a chalk stream, and such waterways are globally rare, with almost a third of the world's chalk streams found in the East of England.

"It will take a while for the fish to recover, so at the moment the impact short-term is huge," said Ms Gough.

"Long-term we will just have to see. Normally nature will do it's thing and can recover quite quickly."

Birds normally seen on the river had disappeared since the foam pollution, Ms Gough said.

"Really what we just want to see this time is some sort of legal action, because we just need things like this to stop, the water is so crucial to all of us."

The foam started to subside on Sunday following heavy rain

Professor Ben Garrod, evolutionary biologist at the University of East Anglia, agreed, saying that unfortunately these polluting events could have a much wider impact.

"The whole thing is connected and what happens in one waterway might affect one that's right near you," he said.

"You might see fewer insects next year in your little stream next year or you might see fewer flowering plants."

Leuan Evans from Thetford Town Council said he was "quite angry" to learn of a second incident.

"We know that some of these chemical pollutants can have impacts on our invertebrates and all sorts of other parts of our bio-diversity and can persist in the environment for a really long time," he said.

The river runs through the town of Thetford with people and pets often swimming in it.

The present advice was for people not to enter the river or let pets drink the water until the contaminant was identified.

The foam was found along the River Thet in the centre of Thetford on Saturday

In a statement, the Environment Agency said: "Specialist officers continue to investigate why a layer of foam, now mostly washed away by rain, appeared on the surface of the River Thet in Thetford on Saturday.

"We've sent water samples for testing to find out more about what happened and why."

The agency also said it would be assessing any "longer-term impacts" on the water course.

It also confirmed its officers had attended an incident involving foam on the River Thet on 23 December last year but had been unable to identify the source on that occasion.

The Environment Agency said it was investigating the cause of the foam