Thames Water has pumped at least 72 billion litres of sewage into the River Thames since 2020 – an amount roughly equal to 29,000 Olympic swimming pools.

The data was obtained by the Liberal Democrats through an environmental Freedom of Information request, as first reported by the BBC. 

The water company discharged at least 14.3 billion litres of sewage into the Thames in 2022, and at least 32 billion in 2021 – making it the worst year on record for sewage discharges into the river.

But the total volume of sewage discharged is likely to be far higher than this. Thames Water only has sewage monitors to measure volume in some locations, which it used during the construction of the Thames Tideway Tunnel. 

Currently, water firms have no legal obligation to report the amount of sewage discharged. They are only required to report the number of hours it was released for. However, the Liberal Democrats have been calling for water companies to be more transparent...