This is why a Sheffield river has turned green

The Porter Brook underwent the lurid transformation yesterday, Thursday, July 22, as the footage shared by Tonia Lucas shows.

Despite initial concerns about a big pollution spill, thankfully it turned out there was nothing sinister behind the dramatic colour change.

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It is believed to have been caused by a green dye pumped into the drains in an attempt to locate a blockage.

Speaking this afternoon, a spokesperson for the Environment Agency said: “The Environment Agency investigated discolouration in the Porter Brook in Sheffield on Thursday 22nd July.

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“The green discolouration is thought to be from fluorescein tracing dye used in drainage systems, which is not harmful to aquatic life and does not present a risk to the environment.

“If you are aware of pollution to our rivers and watercourses, please call the Environment Agency immediately on 0800 80 70 60.”