Severn Trent completes improvements to 1,500 storm overflows – and is now set to deliver a further 600 by autumn 

12th February 2025

Severn Trent has today confirmed it has completed 1,500 engineering projects ahead of schedule and has now unveiled further plans to fast-track the delivery of another 600 improvement projects to reduce the use of storm overflows.  This will bring the number of upgrades, including storm water tanks to hold rainwater and new solutions to treat wastewater, to an industry leading 2,100 projects by autumn 2025. 

Spills to be reduced

The water and wastewater company, which serves four and a half million customers across the Midlands, has today also confirmed that now the 1,500 permanent improvements are installed, the average amount of spills from storm overflows is expected to fall by over 25% to reach an average of 18 per year by December.  With another record year of rain and a hike in extreme weather events, the work is estimated to have resulted in around 24,000 spills from storm overflows being prevented across the region in 2024.

Engineering at speed

In what is a huge engineering programme being delivered at speed, the scale of the project has been made possible by a new dedicated team of 300 Severn Trent engineers. Together, they have delivered an average of 34 projects per week since June 2024, ranging from new storage tanks to capture and store water, to flap valves to prevent flooding when river levels rise. 

The range of engineering solutions that have been delivered include: 

·       244 new storage tanks built and installed at treatment works, some that can hold up to 200,000 litres, to capture and store more water during heavy rain

·       189 flap valves installed across network assets to prevent flooding when river levels rise – which would otherwise overload the capacity of sewers with river water 

·       23 cutting-edge Submerged Aerated Filter units in place at treatment works that help treat more wastewater  

James Jesic, Capital Delivery and Commercial Director at Severn Trent, said: “From new storm tanks to new treatment solutions, we’ve mobilised a huge team of engineers who are working non-stop to deliver for our customers. The team has delivered a major milestone of installing 1,500 overflow improvements, which was made more challenging given the extreme weather events and flooding in many locations. We’re now going even further and even faster by delivering an extra 600 projects by autumn 2025.”

An Advisory Panel has been formed to oversee Severn Trent’s progress against Get River Positive, a series of five industry leading commitments launched in March 2022, to lead the charge in transforming river health across the region. 

Joe Pimblett, CEO, Severn Rivers Trust said, “As an integral partner within an independent Advisory Panel, I have had the opportunity to see how far and fast Severn Trent is moving forward with plans to improve our waterways. Severn Trent’s continuing strong investment in reducing spills is playing a pivotal role in reducing harm in the rivers in my and other regions”

River Chelt overflow sees improvement

Severn Trent expects to see the full region-wide impact of this work during the year ahead as the interventions get up and running, and there is already progress being made at many sites. 

The company has reduced storm overflow spills at one location by 96%. Charlton Kings in Cheltenham, Gloucestershire, had spilled 25 times in 2023. But after a series of investments into monitors, a large new storm tank and improvements to the surrounding pipe network, the spills plummeted to just one in 2024, a fall of some 96% on the previous year.

James Jesic added, “The Charlton Kings project and many others similar serve as a blueprint for the improvements we’re making across our region, as we continue to move at pace to install engineering solutions. As all the improvements get up and running, we’re looking forward to seeing the benefits of this work across the region in the year ahead.”

This announcement is backed by funding secured as part of an additional £1 billion investment from Severn Trent’s investors, to improve the quality of waterways.  Severn Trent’s plans for the next five years will see the company spending over £2 billion on improving river health.  To keep customers updated, Severn Trent has launched an interactive map where anyone can track progress in real time and see what investments are planned. 

The work forms part of Severn Trent’s ‘Get River Positive’ programme, to find out more visit  Get River Positive | Severn Trent Water.  Case studies of Severn Trent’s progress at different sites across the region can be seen here Severn Trent | How we are investing in our region's rivers - YouTube

ENDS 

Notes to editors

  • The majority of the Severn Trent region experienced “exceptionally high rainfall” [1] in 2024.  And there were 19% more extreme weather events last year compared to 2023 – meaning there’s far more rainwater in the network to manage, combined with increased ground saturation. 
  • In 2024 – another record year for rainfall with 1022mm of rain in 2024 vs 973mm of rain in 2023
  • By 2030, the company expects to be on track to reduce storm overflows by an average of 14 spills per year, which is ahead of Government targets.