Water firm United Utilities has been fined £300,000 for contaminating supplies to more than 700,000 people.
Hundreds of thousands of residents in Lancashire had to boil their water in summer 2015 when microbial parasite cryptosporidium was found in the Franklaw water treatment works in Preston.
United Utilities Water Ltd spent £25 million as a result of the contamination, including £18.3 million in voluntary compensation payments to households and businesses, Preston Crown Court heard.
Water firm United Utilities has been fined £300,000 for contaminating tap supplies to more than 700,000 people (file photo)
Sentencing, honorary recorder of Preston Judge Mark Brown said the company failed to carry out risk assessments which could have prevented the outbreak.
He said: ‘It was the largest event of its kind since the privatisation of the water industry many years ago and it had a major impact on day to day water consumption.
‘There was significant disruption to domestic consumers but also to businesses as well.’
Concerned families panicked bough bottles of water from local supermarkets stripping their shelves bare.
But while a great inconvenience was caused to residents, there was no outbreak of illness as a result of the contamination.
However, there was an increase in patients attending GP surgeries, thought to be a result of press coverage, the court heard
Judge Brown said: ‘The event was completely ended by early September. However, it’s likely that in the minds of many customers there would have been ongoing concerns because confidence had been affected.’
He also ordered the company, which has an annual turnover of £1.7 billion, to pay £150,000 costs.
United Utilities pleaded guilty to the charge at Preston Magistrates’ Court in July.
Concerned families panicked bough bottles of water from local supermarkets stripping their shelves bare
Speaking after the sentencing on Tuesday, the firm’s chief executive Steve Mogford said: ‘We are very sorry for the impact this had on our customers.
‘I know from first-hand the inconvenience this incident caused, having lived in Lancashire for 40 years.
‘We have learned valuable lessons from what happened and have put technology and processes in place to guard against a repeat of this type of incident.’
Richard Banwell, prosecuting for the Drinking Water Inspectorate, said temporary operational changes at the Franklaw plant led to contaminated water from an underground reservoir going back into the water treatment facility from July 27 to July 31 2015.
He said: ‘That change in how Franklaw was operating, the redirection of treatment water from Barnacre service reservoir back into the water, was not subject to a risk assessment.’
The court heard there were inherent hazards at the reservoir, including a neighbouring farm, and structural defects at the site led to cryptosporidium getting into the water after a heavy downpour of rain.
Residents in Lancashire had to boil their water in summer 2015 when microbial parasite cryptosporidium (pictured) was found in the Franklaw water treatment works in Preston
The parasite was noticed after it was picked up by a filter system at the Franklaw site on August 5.
The warning for customers to boil their water was issued the next day and stayed in place until early September.
The court heard there was a ‘huge’ impact on the public.
Mr Banwell said one dentist’s surgery had to cancel 100 procedures as a result and could only deal with appointments which were emergencies or did not require water.
He added: ‘No doubt the need to boil water was of significant inconvenience to everybody.’
The court heard ultraviolet irradiation, a treatment which inactivates the parasite, had since been installed after a £100 million investment by the company.
Lisa Roberts QC, defending, said the costs would not be transferred back on to customers.
She said: ‘So far as the company is concerned, it deeply regrets the incident in the summer of 2015 which gave rise to this.
‘It takes its responsibilities to customers very seriously and places their safety at the very forefront of the business.’