Serious pollution incident kills fish in lake
A large number of fish have died and pictures showed water in the lake and nearby streams covered in foam.
The Environment Agency North West described the incident on Twitter as "a serious fish kill".
An investigation into the cause is under way and St Helens Council says it thinks the source of the problem is in the Wigan area.
Residents in the area were warned to keep children and pets away from the water.
The Environment Agency North West thanked fast-acting members of the public for bringing the pollution to its attention as soon as the froth was spotted.
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