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https://environmentagency.blog.gov.uk/2020/07/02/combined-sewer-overflows-explained/

Combined Sewer Overflows Explained

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Combined Sewer Overflows Explained

Recently we have seen prominent coverage in the Guardian which claims that untreated human waste was released into streams and rivers for more than 1.5 million hours in 2019.

There are a number of points that are important to put this article into context.

England has a combined sewage system made up of hundreds of thousands of kilometres of sewers, built by the Victorians, in many urban centres.  This means that clean rainwater and waste water from toilets, bathrooms and kitchens are conveyed in the same pipe to a sewage treatment works.

During heavy rainfall the capacity of these pipes can be exceeded, which means possible inundation of sewage works and the potential to back up and flood peoples’ homes, roads and open spaces, unless it is allowed to spill elsewhere. Combined sewer overflows (CSOs) were developed as overflow valves to reduce the risk of sewage backing up during heavy rainfall.

Overflows of diluted sewage during heavy rainfall are not a sign that the system is faulty. Combined sewer overflows (CSOs) are a necessary part of the existing sewerage system, preventing sewage from flooding homes and businesses.

 

The role of the Environment Agency  

The Environment Agency works closely with water companies to ensure that they are closely monitoring and reporting back on their discharge activity. This data is helping us to understand where the system is not operating as it should, so that water companies can target investigations and investment.

We have already identified over 700 overflows to be investigated and 40 overflows to be improved within the period 2020-2025.

There is still much to do to improve the quality of our water. When water companies do damage the environment, whether it is through polluting our waters or breaching permit conditions, we take enforcement action against them including civil sanctions. We successfully brought forward four water company prosecutions in 2019, resulting in £1,297,000 in fines.

We are also working closely with Defra and Ofwat to drive further improvements. As a result in 2019, Ofwat introduced a package of allowances and incentives for the next five years, setting water companies the challenge of reducing pollution incidents by a third, also requiring them to invest £4.8 billion in environmental improvements.  Since privatisation, water and sewerage companies have improved over 7,000 overflows to secure water quality and amenity benefits Meanwhile we all have a part to play in improving how we use our sewer system.

CSOs can discharge through misuse of the system. Wet wipes make up more than 90 per cent of the material causing sewers to block. We work with partners to raise awareness of this issue and the need to reduce the pressure put on the sewerage system through the #BinIt4Beaches campaigns.

By keeping our sewers free of wet wipes and other sanitary products as well as ensuring fats, oils and grease are not poured down the sink, we can help reduce the need for CSOs.

 

Open water swimming

We also recognise the growing popularity in open water swimming, with many people enjoying wild swimming in rivers.  Public Health England and the Environment Agency offer advice as part of the existing ‘swim healthy’ guidance which is available to read before making any decision on swimming.’ https://www.gov.uk/government/publications/swim-healthy-leaflet/swim-healthy

However, most bathing occurs in coastal waters, for which there are over 400 designated bathing waters in England. There aren’t yet any rivers designated for bathing in England.

Rivers and other open water locations that are not designated as bathing waters are managed for the purpose of protecting fish and wildlife, so health risks from swimming at these locations may be higher than at designated bathing waters.

Managing rivers for bathing presents new challenges in controlling sources of pollution and minimising health risks to create waters suitable for swimming.

For information on over 400 designated bathing waters in England visit www.gov.uk/quality-of-local-bathing-water.

 

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29 comments

  1. Comment by Mike Matthews posted on

    So 7000 overflows improved in 30 years is a rate of 233.3 a year. Good stuff! 40 in the next 5years is 8 a year and that sounds a tad low. So low it suggests your figures are wrong. I'm sure the Guardian will have a calculator to hand to.

    Finally tracking total hours of operation in this way as the population grows might be a reasonably sound metric to use so well done the Guardian

    Reply
  2. Comment by Sbun posted on

    “During heavy rainfall the capacity of these pipes can be exceeded, which means possible inundation of sewage works and the potential to back up and flood peoples’ homes, roads and open spaces, unless it is allowed to spill elsewhere.”

    Clearly the pipes, or the sewage works capacities, are too small, and require investment so that this doesn’t happen. This is what the companies are supposed to do with the money that they get from customers, but instead they take a lot of profit. This is what people are angry about.

    Also, the report states how the companies are releasing sewage very often, far more than is justified, and very often when there is not the level of “heavy rainfall” that justifies these releases. People think they are doing it to save money / make profit.

    Personally I don’t directly blame the EA, as it is a wider fault of DEFRA and the government, and the system we have. But with this sort of weak argument justifying the actions of water companies, instead of calling them out for this behaviour (which is your job) people think you are failing the public. If you can’t do anything about the situation you should at least be monitoring it properly (which you are not currently doing fully) instead of allowing companies to self-report, and providing the information to the public, who pay for you and pay for the water companies.

    Also, it is shocking that this information had to come from a FOI request. What possible justification is there for withholding this information (about the number of times sewage is released) other than to avoid looking like you are failing to do your job to ensure we have the cleanest rivers possible? As I said before, this sort of defensive argument does you no favours. Why not admit that many water companies are regularly polluting rivers when they should not be doing so?

    Reply
  3. Comment by Rat Walton posted on

    What the EA are avoiding telling everyone is that the UK Foreign Owned Privatised Water and Sewage Companies are legally allowed by the EA/Govt to dump and discharge Raw Sewage and Hazardous Wastes via the CSO's, before anything reaches a sewage works and even direct from a sewage works via the CSO's. The Angling Trust and Fish Legal challenged this some years ago, Read – You may be quite shocked at what went on and still is, no doubt.
    ANGLING TRUST – FISH LEGAL 2008
    COMBINED SEWAGE OVERFLOWS (CSOS) AND DEEMED CONSENTS .

    Fish Legal tackles unfinished business from the time of water privatisation….
    Way back in 1989, at the time of water privatisation, the water companies were granted temporary (also sometimes known as ‘deemed’) consents for many thousands of discharges carrying storm sewage into English and Welsh rivers. This followed the discovery, immediately pre-privatisation, that vast numbers of these discharges had no legal consent (a limit on the levels of permitted pollution). At the time, it was quite clear that the granting of temporary consents was supposed to be a quick fix for a couple of years at most, designed to enable the Government of the day to sell the water companies into private hands with no potential criminal liabilities.

    Last year, Fish Legal made requests under freedom of information law to the Environment Agency which revealed that between 3,000 and 4,000 of these temporary consents, granted almost twenty years ago, still existed. None of them had any properly enforceable conditions, meaning they were as good as useless in controlling pollution. This request made to the Agency followed a series of cases of damage to our members’ fisheries caused by sewage discharges from pipes that still enjoyed these temporary consents.
    In 2008, Fish Legal threatened to judicially review the Agency if it failed to deal finally with these deemed consents promptly. As a result, the Agency decided, in April of this year, to impose a set of standard conditions on all those discharges in order to bring them into proper regulation.

    It is those standard conditions against which the water plcs have now, quite shamelessly, appealed. Fish Legal has subsequently made information requests to all water companies concerned in the appeals asking for detailed information about the CSOs and other discharges involved, including asking for records of pollution incidents.
    It is Fish Legal’s belief that the water companies do not know what is discharged from these CSOs and therefore they are simply not in a position to claim that the new determined consents are too onerous.
    There will be a Planning Inspectorate hearing in due course to determine these appeals and Fish Legal hopes to make significant representations to that hearing. Our work on this issue was featured in Private Eye in November (see p.29 of Eye No. 1,249).
    http://www.anglingtrust.net/core/core_picker/download.asp?id=956

    The arguments between the companies and the EA centred on a set of conditions which would make it an offence, for instance, to cause a deterioration in the quality of water in rivers and lakes. Such conditions have now been omitted, leaving a consent which permits the lawful use of the CSOs except in the narrowest of circumstances.
    Fish Legal – which had been invited to take part as an interested party at the hearing in support of the EA – argued that it had investigated pollutions in England caused by discharging CSOs and that the very basic terms of deemed consents had meant that the Agency had been unable to regulate or enforce despite the scale of the damage caused to the environment.’..
    Worth a read of the outcome....Fish Legal, the legal arm of the Angling Trust, has reacted with dismay to the news that six water companies have won their appeal against the decision of Environment Agency (EA) to provide proper regulation for the thousands of unregulated Combined Sewage Overflows (CSOs) in England and Wales. https://www.anglingtrust.net/news.asp?section=29&itemid=528

    Reply
  4. Comment by Windrushwasp posted on

    You say : When water companies do damage the environment, whether it is through polluting our waters or breaching permit conditions, we take enforcement action against them including civil sanctions. We successfully brought forward four water company prosecutions in 2019, resulting in £1,297,000 in fines.
    It seems that most pollutions are not attended,''action'' is seldom taken and most offences are ignored, undiscovered or even covered up.
    4 prosecutions - are you serious? The whole agency achieved 4 prosecutions nationally? No wonder it is cheaper to pollute. Not exactly building any experience for your staff unless there are just 4 of them. The industry must be delighted - especially with you trying to defend the shocking abuses and incompetence revealed by the Guardian.

    Reply
  5. Comment by Sjmalin posted on

    Investment in their failing systems should forced on the water companies. My local river is a shadow of its former self (Windrush, West Oxon).

    Reply
  6. Comment by Anna posted on

    It's an absolute atrocity that water companies are profiting from polluting our water ways. ALl profits made from customers should be put into stopping untreated sewerage entering water ways.

    Reply
  7. Comment by Michael Wingrove posted on

    I am old enough to remember when the water companies were sold off to private enterprise with the promise that these companies would invest in the outdated infrastructure and bring our rivers and seas up to European standards (currently failing).
    Needless to say that hasn't happened because private companies are more interested in looking after shareholders by doing the bare minimum to the infrastructure and investing in the future.
    You are the only organisation who can force these changes to happen. No more houses or commercial premises should be allowed to connect to these overwhelmed sewers until the necessary improvements have been made because that is a big part of the growing problem.
    Any approvals that you grant to water authorities should make it clear that overflows of sewage must only happen during extreme weather events and not every time we get cm of rain. This also needs to be physically monitored to detect when and where offences occur.
    As it stands the EA is not fit for purpose.

    Reply
  8. Comment by joanna Tarasiewicz posted on

    That is just a nonsense and we all know that, including all directors, CEOs and other wealthy people from EA. There is already enough evidence gathered which showed that river is intentionally polluted with nothing to do heavy rainfall, but the evidence is being ignored.
    It's just enough! How dare you?!
    Thames Water should fix the problem and the EA should stop supporting dirty business!

    Reply
  9. Comment by Anne Clements posted on

    No privatised company should be paying a dividend to shareholders or bonuses to employees and CEOs until the sewerage system in this country is fit for purpose, i.e. it should be good enough to cater, not only for the population and weather we currently have, but for the increase in population and the weather we are likely to experience in the future. At the rate quoted there will never be a situation where the companies catch up to where they should be, let alone be future proofed.
    If this scenario is unpalatable to those who are currently making money out of what should be a public service, then the whole industry should be taken back into public ownership.

    Reply
  10. Comment by Jane Brylewski posted on

    I don’t think it is helpful to blame Victorian drains which were not designed to deal with the increased population today. The job of the water companies is to keep the system up to date.
    If rainwater can flood the system this is most likely because of years of neglect and a failure to have modernised the system adequately.
    Many new homes have been built where I live, but I have not seen new sewage plants being built at the same rate to deal with the extra waste. Much of the equipment at sewage plants is old, does break down on occasions and is difficult to maintain. Would an annual MOT, like a car, be helpful? Should necessary improvements be compulsory and inspected.
    The water companies are making profits and paying shareholders which seems wrong when the local environment and public health are at risk.
    There are people in the Environment agency who are keen to do a good job, but at present the regulation of the water companies appears to be lacking in effectiveness.
    Local groups of volunteers are keen to help improve the situation, we all need to work coherently to get any improvement.

    Reply
  11. Comment by Jewel K posted on

    And what investment are you planning for new or bigger sewage facilities?

    Reply
  12. Comment by Angela Hughes posted on

    That is just a nonsense and we all know that, including all directors, CEOs and other wealthy people from EA. There is already enough evidence gathered which showed that river is intentionally polluted with nothing to do heavy rainfall, but the evidence is being ignored.

    Thames Water should fix the problem and the EA should stop supporting dirty business!

    Reply
  13. Comment by Graeme Phillips posted on

    Your job, your mandate, your funding, your existence, your responsibility, is to PROTECT our environment...the clue is in your name! You are not there to be the excuse monkey for a water industry that skims off vast profits, whilst failing to invest in these “Victorian” systems, and is getting away with systematically destroying that environment you are charged with protecting. All we ask is the you DO YOUR JOB! Grow some balls, and hold these water companies to proper account.

    Reply
  14. Comment by Reg Bishop. posted on

    I was born and grew up in Burford and the river Windrush is now a shadow of its former self. The water quality is getting worse and I see no attempt being made to address the problem? There are new housing developments but no expansion of sewerage management infrastructure to handle the extra load. How long can this go on? When will the E.A. demand some positive action? The river I learned to swim in is now toxic!

    Reply
  15. Comment by Neil posted on

    I feel it is a great shame you use the fact the network was built by the Victorians as justification for it failing today. I don't remember reading about the Victorian gas or electricity grids yet they seem to have been installed, maintained and upgraded and isn't the justification of the super sewer that the victorian infrastructure is no longer fit for purpose?

    You also mention there aren't yet any river's designated as bathing waters, but not whether you support or have targets for river sections to gain this status - do you....or shall we blame the Victorians again?

    Reply
  16. Comment by Sophie Bainbridge posted on

    "Managing rivers for bathing presents new challenges in controlling sources of pollution and minimising health risks to create waters suitable for swimming"
    So the rivers are too polluted to swim in !
    this is totally shocking, they are a vital part of the eco system and all the animals birds and insects who rely on them for their water, if any farmer was doing this it would be a national scandal , DEFRA have controls to ensure that this doesn't happen . What sanctions are there for the water companies ?? self regulation ....must be a better solution
    This is totally outrageous

    Reply
  17. Comment by James Bainbr8dge posted on

    The Environment Agency has completely failed in its duties with regard to the pollution of our rivers. When will it wake up and take action against the water companies polluting the River Windrush and the intensive chicken / egg farming polluting the River Wye to name but two examples which I know well. DEFRA and our Government as a whole should press the Environment Agency on this.

    Reply
  18. Comment by James Bainbridge posted on

    The Environment Agency has completely failed in its duties with regard to the pollution of our rivers. When will it wake up and take action against the water companies polluting the River Windrush and the intensive chicken / egg farming polluting the River Wye to name but two examples which I know well. DEFRA and our Government as a whole should press the Environment Agency on this.

    Reply
  19. Comment by Izzy Bainbridge posted on

    What about all the livestock whose main source of water is the river?
    I am having to carry buckets of clean and fresh water everyday into my field for my horses so that they have fresh and clean water to drink as they won’t drink the river water! As any horse owner knows horses only drink clean fresh water.
    There is a reason for the saying - never drink the water your dog drinks but drink the water your horse drinks!

    Reply
  20. Comment by Deirdre Kincaid posted on

    Don't 'explain' it. Bloody well fix it!

    Reply
  21. Comment by Simon H posted on

    Why would an agency which is supposed to protect our rivers allow blatant pollution incidents to go with little or no punishment. Could it be that there is some corruption involved? There can be no other logical explanation.

    Reply
  22. Comment by Andrew Banbury posted on

    What about future planning for the amount of new builds in rural areas . It takes very little time to get planning permission for new estates but it seems no new capacity for the waste waiter produced hence the increased damage to rivers and streams with terrible damage to the already struggling environment

    Reply
  23. Comment by Andrew Banbury posted on

    What about future planning for the amount of new builds in rural areas . It takes very little time to get planning permission for new estates but it seems no new capacity for the waste waiter produced hence the increased damage to rivers and streams with terrible damage to the already struggling environment and no I haven't commented on this subject before so tell your reply system that !!!

    Reply
  24. Comment by Jane posted on

    I also don’t understand why profit made from water companies is not reinvested in making the system more efficient. Given the amount of rain we have all rivers should be clean enough to swim in and for wildlife to thrive.

    Reply
  25. Comment by Serena Martin posted on

    Capacity needs drastc improvement. Of late the use of CSO's has increased as house building has grown. Surely it is not beyond common sense that capacity needs expanding, along with much needed improvements. Wildlife is suffering, with endangered species being particularly hard hit.

    Reply
  26. Comment by Paul arnold posted on

    We have a local brook that children and dogs plan in unaware that raw sewage is dumped in it when it rains. Sanitary products can be seen in the bank side if you know what to look for. Severn trents responce is that we can do it we have a permit, go away. EAs responce is Severn trent have a licence, go away.
    The brook is ultra clean before sewage is dumped in three locations. If you then take the trouble to walk the brook to where all the solids settle you find a horrendous environmental mess of sanitary waste, look the other way you wont see it or have to do anything about it ! In this day and age we should be more responsible fo the environment and leave it better than we found it . Should be as a minimum putting in a screen to prevent the solids entering the water course but the water companies just pass on the blame rather than providing a solution.
    Water companies and the environmental agency shame on you!
    I will take you to the site at any time to see if you would like to use your enforcement powers

    Reply
    • Replies to Paul arnold>

      Comment by Geoff Tombs posted on

      Paul, if it as bad as you say call the EA incident line on 0800 807060 and report the incident. You should get an incident ref number and the EA should follow up and investigate. Evidence of sewage fungus or fish mortalities usually gets them motivated. Keep up the pressure.

      Reply
  27. Comment by Mrs. Lucy Simpson posted on

    To the Environment Agency - Stop lying to us. It is absolutely disgusting that this has been allowed to happen over many, many years. I first noticed how polluted the River Windrush was 3 years ago and at that time was so upset. It was fortuitious that WASP Windrush Against Sewage Pollution came to my attention. Now the public have a voice and at last pressure can be put on local politicians and the Agencies responsible for this.

    Reply
  28. Comment by Richard Martin posted on

    One of England's glories is the clean, drinkable water that flows from our taps... thank you, water companies.
    And thank you, also, for taking pollution seriously, and helping to improve river quality. At a time when air quality worsens and litter abounds, it is good to know some things are getting better.

    Reply

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