Our national body The Rivers Trust responds to the Environment Agency’s (EA) 2021 raw sewage releases statistics. 

Yet again, shocking numbers for the level of sewage pollution from storm overflows in England and Wales show that water companies are barely starting to get to grips with the scale of the problem.

The EA shared the statistics on 31 March, showing how much raw sewage was released in England in 2021 – 2.66 million hours overall on 372,533 occasions.  

This represents a small decrease on prior numbers, which may be due to the slightly lower average rainfall overall in England in 2021. The average number of spills per monitored CSO declined by four spills p.a from 33 to 29.  There is no information supplied which indicates why spills have declined, so we can’t attribute this slight improvement to any particular drivers. 

More sites are monitored and that represents progress.  In Wales there is 99% coverage of known overflows and in England, we are now up to 89% (from 80% last year). The format of the reporting has also improved, making it easier to interpret and cross reference. 

The EA summarises the reason for high spillers, where CSOs are spilling above a threshold of 60 times p.a. These are the worst performers in the system, and account for 16% of all CSOs (down from 19% in 2020).

Water companies only know the reason for high levels of spills at 44% of those CSOs. And of those, only 2% (in Anglian and Southern Water) are due to exceptional weather. 29% were due to operational issues, which could encompass a broad range of things including inadequate maintenance. 70% were due to the hydraulic capacity of the system, in other words the sewer system cannot cope with the current waste water volumes. This indicates that 98% of the known reasons for very high unacceptable levels of spilling are due to poor management and under-investment in the sewer system. The numbers clearly support the claim that investment by water companies in our sewer system has lagged to the point that it is already not fit for purpose, much less ready for a future of climate extremes and further population growth.

Christine Colvin, Director for Partnerships & Communications at The Rivers Trust, said: “The data that we’ve seen today serves to highlight the low level of ambition in the Consultation Plan from Defra.

“The plan aims to improve 52% of storm overflows by 2040, so that they’re not spilling more than 10 times per year.

“Today’s EA data shows us that 40% are already recording 10 spills or less.  We want to see much more ambition to reduce spills overall and protect sites that are important for people and wildlife.” 

The full dataset is available at https://environment.data.gov.uk/dataset/21e15f12-0df8-4bfc-b763-45226c16a8ac

View The River Trust’s sewage map at https://theriverstrust.org/key-issues/sewage-in-rivers