The vigilance of a London Wildlife Trust conservationist helped avoid a major pollution incident in a west London river in September after sewage water was spotted flowing into the River Crane.
Senior conversation officer Tom White noticed sewage fungus growing on the river bed and reported his finding to the Environment Agency (EA).
An investigation found polluted water flowing into the river near Great South-West Road in Hounslow .
'I knew the river was in trouble'
Mr White said: “As soon as I saw the distinctive signs of sewage fungus I knew the river was in trouble.
“Last year the river was restocked with thousands of fish including chub, dace, roach and barbel, but a pollution incident like this could have decimated fish stocks and impacted hard on the wildlife that lives along the river.”
The EA retrieved reports of around 300 distressed fish in the area, who reported their findings to Thames Water who carried out an investigation.
Blockage found in Hounslow
A blockage was identified by Thames Water on Wednesday September 15 in Bath Road in Hounslow, which was causing sewage to overflow into a surface water pipe that led to the river.
The blockage was caused by a build up of fat, oil and grease in a sewer.
Environmental projects executive for Thames Water, Claudia Innes, said: “Thanks to the quick actions of London Wildlife Trust and the Environment Agency we were able to find and deal with this sewer blockage in tiem to stop damage to the river.
“We really can't stress enough that homes and business should not pour cooking oil down their sinks.
'Putting homes at risk'
She added: “When sewers become blocked with fat, oil and grease, as well as putting homes at risk of sewer flooding, it can find its way into and cause untold damage to wonderful rivers like the crane, which should otherwise be teeming with life.”
The River Crane is a tributary of the Thames and travels from its source in Hayes through Hounslow and Richmond.