SEWAGE DISCHARGES

  • Written by Andrew Davis
  • Posted on Nov 25, 2021
  • Articles

Somewhat surprisingly, the Thames is the most photogenic of all rivers according to an American travel website.  To demonstrate that claim, it has found that the Thames is mentioned more frequently on Instagram than any other river in Europe.  Even more surprising is a report from the Zoological Society of London which states that the Thames is ‘a rich and varied home for wildlife’ after being declared biologically dead sixty years ago.

And yet there has been a lot of publicity recently about the discharge of raw sewage into rivers and coastal waters.  There has been passionate debate during the passage of the Environment Bill, now enacted, through both Houses of Parliament with claims that the Government is not taking enough action to remedy the situation, specifically that the powers conferred by the Act are not sufficient to force water companies to stop the practice.  Despite numerous amendments and intense lobbying, the Act only requires the Government to ensure that water companies secure a progressive reduction in the adverse impacts of discharges from storm overflows.

The problem arises because the water companies have a derogation to discharge raw sewage in exceptional circumstances.  Effectively that means when heavy rainfall threatens to overload the sewers, bringing the risk that the contents might back up into people’s homes or overflow from manholes in the street.  Whilst that is understandable, especially as climate change causes ever heavier rainfall, there is evidence that the derogation is being abused.

The practice is far more widespread than might be justified by exceptionally heavy rainfall.  Last year, according to a recent Environment Agency report, there were 403,000 separate incidents of raw sewage being discharged into rivers, up from 293,000 in 2019, and that these covered more than three million hours or pumping!  The material let into watercourses included untreated sewage, cotton buds, used condoms and the wet wipes that make up 90% of the matter causing sewers to block.

In mitigation, Water UK, the body that represents water companies, claims that £1.1 billion is being invested over the next five years, part of a wider £5 billion programme of environmental improvements.

Whilst these discharges are legal, there is evidence that far more sewage ends up in our rivers and coastal waters illegally.  A report commissioned by the Environment Minister Rebecca Pow earlier this year found that such illegal discharges are running at least ten times greater than prosecutions by the Environment Agency indicate.  In the decade from 2010 to 2020, there were 174 prosecutions for illegal discharge but the investigation looked at 83 sewage plants and suggested at least 2,197 potential breaches.  Part of the problem is that it is up to the water companies themselves to monitor the discharges with the temptation to cover up illegal activity.

This is not just happening in major conurbations, it is widespread across the country.  A recent press release from Action for the River Kennet (ARK) claims that the sewage treatment works in Marlborough, Burghfield and Stratfield Mortimer discharged untreated sewage into the River Kennet, Burfield Brook and Clayhill Brook for more than a third of last year.  Those are just three examples in the Kennet catchment alone that cannot be justified by exceptionally heavy rainfall.

The European Water Framework Directive that came into force in 2000 required member states to ensure that all water bodies achieved good ecological status by 2015.  Yet, by 2015, the target was missed as 47% failed to meet the threshold, so the deadline was extended to 2021 and then again to 2027.  Although no longer bound by European legislation, the principles were transposed into UK law and have been further amended by the Environment Act.

Whilst the definitions have changed over the years so that figures are not directly comparable, it was shocking to find in the report on our water bodies published by the Environment Agency last year that only 16% achieved good ecological status, only 14% for rivers.  This had not changed since the previous report in 2016, indicating a total lack of progress.  It is true that this is not solely due to the discharges from sewage works and that extreme rainfall events are becoming more frequent.  Farming must take its share of the blame with soil erosion and diffuse pollution from arable fields as well as run-off from roads continuing to reduce water quality.

It is also true that there is investment and that remedial action is being taken.  As new homes are built and connected to the sewage system, the extra volume must be taken into account.  There has been development work taking place at the Kintbury sewage work for months, presumably increasing treatment capacity, part of the investment that Water UK reports.  One mitigating action would be to keep rainfall out of the sewer network, having a separate system of balancing ponds to take the excess water, or for households to collect rainwater for recycling.

Whilst the media has been dominated by climate change in recent weeks due to the COP26 summit held in Glasgow, the fate of our environment and the wildlife it supports is related and equally important.  The Environment Agency and the regulator Ofwat have now launched enquiries into the illegal discharge of sewage but not before time.  Any fines imposed should be spent on improvements to the sewage system.  There has been a woeful lack of investment in infrastructure over many decades, particularly when utility companies were state owned before privatisation.  The huge investment needed now will have to be met by the consumer unless the Government is prepared to help with taxpayers’ funds.  Wherever the resources are found, the work is essential as it is a national disgrace that we are still polluting our waters with vast amounts of raw sewage.