Severn Trent's water bungle

Thousands of householders in parts of Shropshire received water with double the required amount of fluoride following a blunder by Severn Trent, it emerged today.

A total of 28,743 people in Bridgnorth and Wolverhampton were affected by the incident, following the mistake by an unqualified worker at Severn Trent's Dimmingsdale works, near Wolverhampton.

The Drinking Water Inspectorate has been highly critical of the error, which posed no threat to public health.

The fluoride was added by an unqualified worker and Severn Trent then tested the wrong taps. Some households received twice the required amount of fluoride.

Severn Trent admitted an error and has since strengthened procedures, it said today. It repaired faulty equipment, retrained staff, reviewed procedures and sampled the affected area.

Today David Wickens, from Severn Trent, said: "The dosing equipment was attended to by an engineer who had not got the correct qualifications.

"The level of fluoride that we would normally treat to would be 1mg per litre and the maximum that it went up to was 2mg per litre.

"The health professionals said there was no risk. We've put in a training programme to ensure it doesn't happen again."

A report from the Drinking Water Inspectorate said the incident had involved a catalogue of errors.

Officers had made 14 recommendations in order to prevent a recurrence of the problem.

Severn Trent had failed to notify the Inspectorate, did not liaise with local and health authorities, had been guilty of inadequate follow-up sampling, inadequate investigations into the root cause and inadequate training of staff, the report said.

The report said: "In June and July, water leaving the works contained more fluoride than permitted, which went undetected because work being carried out to install new equipment was inadequately supervised.

"The company had not complied with many aspects of the Code of Practice on Technical Aspects of Fluoridation 2005."

Water at Dimmingsdale works is fluoridated as part of a legal agreement with West Midlands Strategic Health Authority