Local people were shocked to see a four metre high wall of foam covering the river.

The spillage happened in the Bishops Stortford area and the foam was worst along the section from Grange Paddocks, through South Mill Lock to Twyford Lock.

For the full story, including photos and film footage of the foam, visit the Herts Observer website.

Design by LTD Design Consultants and build by Garganey Consulting.