Severn Trent embarks on huge engineering programme which will reduce spills at 40% of active storm overflow sites 

17th May 2024

·         Following its £1bn equity raise in October 2023, Severn Trent unveils its plan to deliver storm overflow solutions across 900 locations in the Midlands

·         This work is in addition to its existing work to improve river health and improve its waste water network, bringing total investment for 2024/25 to £450m

·         Following extensive work to test and trial solutions, the 300 strong team are now installing c.1,000 capital schemes which, once finished,
will see a reduction of 20% of spills per year.

This region-wide programme of capital investment is already underway, and once complete, 20% of spills from storm overflows will be eradicated.  This accelerated programme of initiatives will run through the rest of 2024 and into early 2025. The company will deliver almost 1,000 separate improvements across c.900 sites in 2024 alone.

The plan released today features a range of initiatives including:

·         700 new storage solutions for installation at treatment works to capture and store more flows during high rainfall to dramatically reduce spills 

·         A large-scale community trial, supplying 8,000 free water butts across 10 communities to reduce surface water going into drains

·         New ‘nature based’ solutions including the creation of more than 70 reed beds to treat sewage at the storm route for storm overflows 

·         25 treatment units to expand the treatment capacity through the additional processes, dramatically reducing spills 

·         198 enhancements to increase the flow of sewage to treatment works

·         130 FLAP valves that prevent river ingress into the network, which would otherwise overload the capacity of sewers with river water

·         300 expert engineers and data scientists working in a Zero Spills Hub dedicated to storm overflow improvements 

·         A new international collaboration partnership programme bringing together water companies and academics from around the world to find world leading innovations to reduce             spills more quickly 

Liv Garfield, Chief Executive Officer, Severn Trent said: ‘’Our customers have told us they want us to reduce spills from storm overflows and we have promised to go as quickly as possible to deliver that. 

“This is why we’ve had an army of 300 engineers and data scientists working around the clock to test and trial a whole range of capital schemes to reduce spills from storm overflows – with the first storage tanks already in and to be delivered at pace each week.   

“Behind the scenes we’ve been working flat out to find new and agile ways of delivering complex capital schemes much quicker. At our peak we’ll be building up to 40 tanks a week. We won’t stop working on this until we’ve delivered on our targets.

‘’Since we launched Get River Positive two years ago, we’ve already made large-scale infrastructure improvements. Our share of impact on the health of our region’s rivers has fallen to 14% and we are confident this time next year our impact will have fallen to 10%. This will mean that 9 in 10 reasons for rivers in the Midlands not achieving good ecological status will be down to other sectors.’’

Severn Trent has both increased and accelerated investment behind its storm overflow spill reduction plan after the company raised £1 billion of funding from its investors in late 2023. Severn Trent had previously allocated £384m of investment for this capital delivery work in 2024/25 but that investment has now increased to £450m, and it will be delivered at speed.

Severn Trent has 2,472 storm overflows, more than any other water company given its region does not have a coastline, although around 350 storm overflows have not spilled in the last year. This year will see over 900 (over 40%) prioritised for action, and the company has plans in place to improve the remaining in close succession.

Last year the company reported 60,253 spills from storm overflows in an exceptionally rainy year. Today’s announced schemes would have reduced those spills by 20%. 

As schemes progress, more detail will be shared on what action is planned for every storm overflow in every waterbody. A storm overflow map has been launched which is a great tool for people to see what investment plans are taking place on all storm overflows across the region. 

Severn Trent has been recognised as an industry leader when it comes to environmental performance, achieving the Environment Agency’s highest four-star rating for four years running. It is confident of securing this for an unprecedented fifth year later in July 2024.

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What are RNAGS?

RNAGS means “Reasons for Not Achieving Good Status”. River health in the UK is measured by the Environment Agency (EA). All waterbodies aim to achieve Good Ecological Status, which means that the river is as close to its natural state as possible. The EA measure this by dividing the river systems into smaller units called water bodies where they then look at a range of aspects including the amount and size of fish and other species, and the presence of chemicals like phosphate, ammonia and dissolved oxygen.