Water utilities company Thames Water Utilities was fined £50,000 on July 2 for polluting a five-mile stretch of the River Thame killing an estimated 15,000 fish.
During the five-day long trial, the court heard how pump failures at Thames Water’s sewage treatment works in Aylesbury led to a significant discharge of untreated sewage effluent into the River Thame on July 8 and 9, 2002.
An investigation by the Environment Agency, which brought the prosecution, revealed two of the plant’s three pumps used to pump sewage for treatment had been out of action for a number of weeks, with one being out of action since May.
Although Thames Water had a third standby pump as well as a storm pump which could be used to pump sewage to treatment, the third pump also failed on July 8 2002, causing two further storm pumps to come on line and pump sewage into the works’ storm storage tanks.
It was hoped that the pumps could be repaired and the stored sewage could be pumped back into the works for treatment. But, it then started to rain and, as the storm pumps continued to pump to the already brimful storm tanks, millions of litres of untreated sewage were flushed out into the river.
Agency officers, alerted to the incident by Thames Water shortly before midnight on July 8, deployed aeration equipment in an attempt to raise the dissolved oxygen levels the following day. Untreated sewage can have a devastating effect on the environment as it contains high levels of poisonous ammonia, which is directly lethal to fish, as well as bacteria and pathogens which reduce dissolved oxygen levels vital to sustain river life.
In court, Thames Water argued the discharge was legal under its consent to release excess rainwater combined with sewage after periods of heavy rainfall.
However, in delivering a guilty verdict the court found, following a legal definition of ‘storm sewage’ given by the Judge, that the discharge could not be regarded as a storm sewage, and therefore, that the consent did not apply.
Investigating environment officer for the Agency Jeremy Churchill said: ‘Companies must ensure they maintain equipment for the protection of the environment to a high standard, as failure to do so can have a serious impact on river life.’
‘Our investigation revealed a serious lapse in environmental procedures at Aylesbury Sewage Treatment Works which caused a pollution incident killing 15,000 fish.’
In issuing fines of £50,000, Judge Rodwell highlighted the management failures within the company, and that in future Thames Water should carry out repairs quickly.
Thames Water was fined £50,000 for two counts under s.85(1) of the UK Water Resources Act 1991 and was ordered to pay costs of £20,005.
Source: UK Environment Agency