More than two billion litres of raw sewage flowed into the Thames in two days from a waste water treatment plant, a report has found.
Thames Water, which runs the Mogden water treatment works where the October 2020 incident took place, admitted it was “unacceptable”.
Parliaments environmental audit committee published a report which found that on October 3 and 4 the west London plant “spilled 1 billion litres plus, which is the equivalent of 400 Olympic-sized swimming pools of sewage each day.” That is the equivalent of sixteen Olympic swimming pools an hour for two days.
October 3 and 4 were among the wettest days on record. Water companies are legally allowed to discharge waste water into rivers if they are at risk of becoming overwhelmed, to prevent possible leaks into the streets or people’s homes.
Thames Water’s chief executive Sarah Bentley said that the company would have had to have another facility the same size as Mogden to cope with the rainfall on those two days.
A spokesperson for Thames Water said: “We regard all discharges of untreated sewage as unacceptable and will work with the government, Ofwat and the Environment Agency to accelerate work to stop them being necessary.
“Our aim will always be to try and do the right thing for our rivers and for the communities who love and value them. We have a long way to go – and we certainly can’t do it on our own – but the ambition is clear.