Sewage dumping in London increased five-fold in 2023

The figures have been branded ‘scandalous’ by the city’s Mayor Sadiq Khan, who has now written to Thames Water’s new CEO demanding action.

The analysis, conducted by City Hall, found that sewage was allowed to spill into waterways across the UK capital for a total of 6,590 hours, 11 minutes and 54 seconds over the course of last year. 

Five times more pollution events than in 2022, 128 hours of discharge occured in just six days between Christmas and New Year, equivalent to 18 hours per day during that period. Treated sewage and outflows of untreated sewage contributed to the issue, along with storm water pouring into rivers due to storms and extreme weather. Data was taken from 118 individual sites, which feed 33 rivers and waterways. 

In response to the statistics, Mayor of London Sadiq Khan has written to Thames Water CEO Chris Weston, highlighting the scale of the challenge created through decades of infrastructure disrepair and neglect. He has also asked for reassurance the organisation ‘will fulfil its obligations on environment including cleaning up our rivers and tackle pollution discharge’. 

Additionally, Khan has called on the UK Government to take action by developing a new plan to return Thames Water back to financial health, without delaying river clean ups, deliver essential water network upgrades without increasing bills, and introduce tougher legislation to force water companies to end sewage discharge into rivers. This would include tougher financial penalties.

‘London’s rivers are the arteries of our city. Frankly the current state of some of our rivers is appalling and only getting worse,’ said Khan. ‘Thames Water urgently need to up their up their game, and get a grip of the situation. At the same time, ministers are standing by and letting more and more dirty sewage flow into our rivers. We need tougher legislation that forces water companies to act as a matter of urgency. While we’re making huge progress cleaning up London’s air and much of the capital’s environment, it’s a scandal that levels of sewage in our rivers are increasing at the same time.’

‘With the London Mayoral election just a few weeks away, it is essential that the public sees a genuine commitment to urgency and leadership from City Hall to tackle the dreadful state of the River Thames,’ added James Wallace, CEO of the campaign group, River Action. For decades Thames Water has got away with polluting our waterways, wasting drinking water and threatening the health and livelihoods of Londoners with impunity… As cyclical floods and droughts worsen and the impact of aging infrastructure and population growth hit the most vulnerable and our precious wildlife, we need the Mayor of London to prioritise water quality and supply alongside other essential services.’