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The European standard for the maximum permitted level of fluoride in drinking water (1.5mg/l) is enshrined in the Water Supply (Water Quality) Regulations 2000 (as amended). The Drinking Water Inspectorate is the enforcement body for these regulations.
Water authorities ceased to exist on privatisation of the water industry in 1989. Water companies are required to notify the Inspectorate of any breach of regulatory standards and the Inspectorate independently assesses the actions taken by the company.
Since 1997 there have been three occasions when the Inspectorate has been notified of fluoride exceeding the standard in England or Wales, as follows:
Occasions of fluoride exceeding the standard Water company 1997 None — 1998 None — 1999 None — 2000 1 Three Valleys Water 2001 None — 2002 None — 2003 None — 2004 1 Hartlepool Water 2005 None — 2006 None — 2007 None — 2008 1 Severn Trent Water