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16 October 2017

More than a third (40%) of rivers in England and Wales are polluted with sewage adding to one of ‘the most urgent environmental crises facing the UK today,’ WWF investigation warns

Water companies and the government are failing to prevent avoidable sewage pollution, leaving our rivers unhealthy and putting wildlife and people at risk - a nine-month long investigation into the sewerage system by conservation charity WWF has revealed.

Nearly 18,000 (17,684) licensed emergency sewer overflows – managed by water companies across England and Wales - are meant to discharge raw sewage directly into the environment only during extreme rainfall, but WWF has found they are discharging far more frequently.

A total of 1,902 pollution incidents were reported by the nine water and sewerage companies operating in England alone, a first rise in incidences since 2012. There was also an increase in the most serious pollution incidents, all of which were associated with sewage.

South West Water, which operates in Devon, Cornwall, and small areas of Dorset and Somerset, reported by far the most sewage pollution incidents in 2016 with 115 sewage pollution incidents per 10,000km. This was followed by Yorkshire Water which reported 46 sewage pollution incidents, and Northumbrian Water which reported 38. At the more positive end of the scale, United Utilities, which operates in the North West of England, reported 22 sewage pollution incidents.

This is likely to be just the tip of the iceberg because wastewater legally discharged continuously from sewage treatment works - also managed by water companies - is not being treated to high enough standards to protect rivers, even though sewage pollution causes rapid algae growth, starving rivers of the oxygen that insects, fish and other wildlife need to survive, which in turn also affects animals such as otters and kingfishers at the top of the aquatic food chain.

These findings come just months after Thames Water was fined £20m for sewage spills in its region over 2012-2014, which is by far the largest fine any UK water company has ever been landed with.

Ben Stafford, Head of Campaigns at WWF, says:

“The problem of sewage pollution stems from multiple failings, including lack of proper planning and investment in our sewerage system; shortcomings in monitoring, risk assessments, operational practice and staff culture; and insufficient regulation. And many of us are also contributing to the problem of sewer overflows by flushing items such as wet wipes, sanitary products and kitchen fat down toilets and drains.

“No one party can fix this problem. Water companies clearly have a key role to play, but we also need greater action through regulation - it should not be legally acceptable to pollute our rivers or frequently discharge untreated sewage.

“We want to see water companies produce long-term wastewater plans that ensure the sewage system is sufficient to prevent pollution and cope with today’s downpours, future climate change, increasing urbanisation and population growth. We want to see the UK government and the Welsh government make these plans a legal requirement”

The water industry and agriculture are the main sectors responsible for failing river health, and four out of five rivers (80%) in England and Wales are currently failing to achieve ‘good ecological status’. The regions most affected by wastewater pollution are served by Thames Water, Southern Water, and Severn Trent Water.

The Environment Agency is scaling up monitoring on sewer overflows and there is an initiative - called the 21st Century Drainage Programme - to assess the capacity of sewers, develop a framework for wastewater planning and address sewer misuse by the public. At present neither the Environment Agency nor water companies know the total volume of sewage being discharged into the environment, which is a huge concern.

Through its #NatureNeedsYou campaign, WWF is calling on the UK government to act on its commitment to deliver a ‘green Brexit’ by ensuring at least 75% of our rivers reach ‘good ecological status’ by 2027. This target for improvement was set by EU legislation which the UK helped shape, but as we prepare to leave the EU the UK government isn’t remotely on course to achieve it.

  1. fact, the situation is getting worse – the number of healthy rivers in England has declined from 27% in 2010 to 14% in 2017. If this rate of decline continues, by 2025 we might be left with no healthy rivers.

All sorts of bacteria, pathogens and parasites in untreated sewage can threaten people’s health too. Anyone whose hobby or profession brings them into contact with potentially infected water – surfers, rowers, anglers and wild swimmers for example – is at risk of a mild to bad case of gastroenteritis such as E.coli or salmonella, which can be serious. Diseases such as leptospirosis, septicaemia and hepatitis A are all linked to sewage pollution and can sometimes be fatal.

WWF has launched an interactive map where people can find out the state of their local river and send a message to their MP to ask him or her to put pressure on Environment Secretary Michael Gove to act.

To join WWF and demand the UK government protects and restores rivers in England and Wales, visit:


Footage and images

Of recent sewage overflows collected by WWF in England available here

Spokespeople available for interview on request

Ben Stafford, Head of Campaigns at WWF

Catherine Moncrieff, Freshwater Policy and Programme Manager at WWF

Notes to the editor

• The full report is available at

• WWF’s report “Flushed Away” recommends urgent action: “We ask the government to fully transpose the EU Water Framework Directive and the Urban Waste Treatment Directive into law in England and Wales/ In addition, we ask that the government mandates water companies to develop long-term strategic wastewater management plans to improve river health; and ensure that the environmental regulators review all existing permits relating to sewage treatment and discharge. We ask Ofwat and water companies to contribute to good ecological status of rivers through the 2020-2025 business plans, and that Ofwat recognise it as a common performance commitment.

• Sewage overflows are specific places, managed by water companies, designed to release untreated sewage as an emergency relief mechanism. Almost 90% of the 18,000 sewer overflows across England and Wales discharge sewage directly into rivers.

• A ‘pollution incident’ is an individual event that has caused environmental harm. These are categorised according to the extent of harm, with ‘serious’ pollution incidents causing significant fish deaths and risk to public health.

• The threats to the UK’s wetland environment are just one example of a growing environmental crisis, with the climate warming and global wildlife populations set to decline 67% from 1970-2020, according to the Living Planet Report (2016). Without political leadership, none of these problems will be tackled. People want the UK to be a leader on the environment which is why WWF is calling on the UK government to champion environmental issues, including restoring the health of our rivers.

• WWF is one of the world’s largest and most respected independent conservation organizations, with over 5 million supporters and a global network active in over 100 countries. WWF's mission is to stop the degradation of the Earth's natural environment and to build a future in which humans live in harmony with nature, by conserving the world's biological diversity, ensuring that the use of renewable natural resources is sustainable, and promoting the reduction of pollution and wasteful consumption.


Sewage pollution incidents (per 10,000km of sewers) in 2016

United Utilities 22

Wessex Water 22

Welsh Water 30

Severn Trent Water 30

Anglian Water 32

Thames Water 33

Southern Water 35

Northumbrian Water 38

Yorkshire Water 46

South West Water 115

Source: Discover Water