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British waterways fight invasion by Russian zebra mussels

4 August 2011 Last updated at 06:51 BST

Water companies say they may have found a solution to the spread of an invasive Russian mollusc which is clogging waterways.

The zebra mussel costs Anglian Water alone £500,000 a year to remove from treatment plants.

As Danny Savage reports, it is hoped a new powder will kill them off.