Raw sewage pollution was a factor in the deaths of hundreds of fish in the River Foss in York last month.
That’s the belief of the River Foss Society following a probe by University of York scientists.
YorkMix reported that the dead fish could be seen in the river next to both Foss Islands Road and Huntington Road on 22 June.
The Environment Agency said they believed the most likely cause of the deaths was low oxygen levels in the water due to the high temperatures and low atmospheric pressure.
Yorkshire Water say they visited the Foss after the fish die-off and found no sewage present in the water.
However, councillors have since said that tests by University of York scientists did suggest raw sewage was a factor.
Mike Gray, events organiser for the River Foss Society, said they agreed.
“The level of paracetamol that was found in the river by York University scientists was interesting,” he told YorkMix.
“When you get high levels of paracetamol in the river, you know there’s raw sewage involved.
“We know the fish kill was quite limited and started by the old railway bridge down Huntington Road.
“While we can’t quite work out what’s killed them you can be sure it wasn’t just lack of oxygen as the Environment Agency and Yorkshire Water tried to claim.
“I doubt we will ever find out exactly what happened but definitely there was sewage put into the river, higher up by Earswick.”
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