HARMLESS: Environment Agency said the discolouration is drain dye. Picture: Chris Barber
LANCASHIRE Telegraph reader Chris Barber sent in this picture of a very green Showley Brook in Wilpshire.
Environment Agency bosses said the substance is a drain tracing dye which helps find leaks, drain damage and contamination.
A spokeswoman said: "It is completely harmless to the watercourse and it will disperse very quickly."
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