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Environment Agency bathing waters storm overflow data

Posted by: , Posted on: - Categories: Environment Agency, Water

The Environment Agency has analysed Event Duration Monitoring data on storm overflows associated with bathing waters across England for 2023. This data, provided to the EA following the end of the bathing water season (May to September inclusive), is a vital tool for the organisation to plan what work needs to take place ahead of the next season and to work with water companies and local organisations to take action where needed.

Bathing water quality has improved significantly over recent decades; 28% of bathing waters were rated as ‘good’ or ‘excellent’ in the 1990s, and 76% in 2010. It is now 90%, with 96% reaching minimum standards. You can read more about the annual results published earlier this month.

An Environment Agency spokesperson said:

Event Duration Monitoring gives us much more information on where and when storm overflow discharges are occurring, which is enabling us to take quicker action to improve them. The transparency this monitoring provides is critical to tacking the problem, and if we identify illegal discharges from storm overflows we will investigate them and take action.

96% of bathing waters meet minimum standards and we are taking targeted action at all ‘poor’ bathing waters which may be affected by sewage discharges, agriculture and urban run-off. Over the last 30 years, we have directed £30 billion of water company investment in sewerage improvements and other measures to improve and protect water quality.

We take our responsibility to protect the environment very seriously and regulate water companies in their operation of storm overflows to ensure they only discharge under strict permitted conditions. We are also strengthening our regulation by expanding our specialised workforce, increasing compliance checks and using new data and intelligence tools to inform our work.

The data shows that the average number of discharges from storm overflows in a bathing water is 8.4 for an average duration of 3.7 hours. This is an increase from an average of 5.6 spills per overflow and an average duration of 3.2 hours in 2022. This increase is largely explained by the increased rainfall during the 2023 bathing water season (353.7mm, 111% of the long-term average) compared to the 2022 bathing water season (236.5mm, 74% of the long-term average).

Across the whole network the EA has required water companies to fit monitors to storm overflows to increase transparency. This includes any which impact bathing waters – 99% of which (1,037) now have an EDM monitor installed.

The data analysed is a sub-set of the EDM data for all storm overflows, which is published in March annually. This data, provided to the EA following the end of the bathing water season (May to September inclusive), is used after the bathing water season to help us plan what work needs to take place ahead of the next season – allowing us to take action where needed.

Wider measures from the government and Environment Agency to improve water quality include:

  • A requirement for water companies to fit monitors to all storm overflows, increasing from 10% in 2015 to 91% in 2022. It is expected to reach 100% cover by the end of this year.
  • Supporting farmers to reduce water pollution and an increase in agricultural regulation. The Environment Agency carried out more than 4,000 farm inspections across England last year, helping farmers comply with legal requirements and resulting in more than 5,000 actions undertaken to improve farm practices and drive improvements to our environment.
  • Setting strict targets for water companies to reduce the impact of storm overflows. This has led to the largest infrastructure programme in water company history with £60 billion to be invested over the next 25 years, preventing hundreds of thousands of sewage overflows every year.

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  1. Comment by Ian Gregory posted on

    Wouldn't it just be easier to say don't swim in our rivers. Forget the sewage what about the decomposing wild life and rat urine.

  2. Comment by John Crouch posted on

    Our section of the Great Ouse through Bedfordshire (Olney through Bedford) is not classified as a bathing Water although several sections are commonly used for recreational bathing indeed Odell Parish Council is negotiating to acquiring a section of land fronting the river for communal use. Which department should I contact to register an interest to have this body of water reclassified as Bathing Water.


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