Why is our water so polluted?

A new investigation or report into the state of our water seems to come out every week. We all know that our rivers, seas and waterways are far from clean. But why?

Water companies have been under heavy fire for huge bill increases and executive bonuses coming alongside endless tales of untreated sewage being released into our waterways.

In July, water companies signed up to reforms set out by the new Labour government to clean up England's water. These include ring-fenced funding for infrastructure improvements, as well as more compensation when things go wrong.

The Department for Environment Food and Rural Affairs (DEFRA) has unveiled five key priorities, with water right at the top of the list. Plus, new Environment Secretary Steve Reed has committed to 'clean up' the water industry.

But why are we in the situation we are in now? We've looked into exactly what's going wrong.

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What's the issue with our water?

There's not a single river stretch in England that's currently considered to be in 'good' overall health, according to the 'State of our Rivers' report recently published by The Rivers Trust. 

The report found that 85% of river stretches fell below 'good ecological standards'. 

It's a similar story in Northern Ireland; again, 0% were found to be in good overall health. 69% of river stretches fell below 'good ecological standards'.

Wales fares better, with 44% of stretches achieving at least good status. However, Afonydd Cymru (Wales’s version of The Rivers Trust) has concerns about the way in which assessments are being carried out, as the methods do not include fully accounting for a group of chemicals known as uPBTs, or 'ubiquitous persistent, bioaccumulative and toxic chemicals'. 

In Scotland, known for its clean water, the report found 57% of river stretches to be in good overall health. Despite that, The Rivers and Fisheries Trust still has concerns about what the future holds.

Our beaches are under threat too. The amount of sewage discharged into the sea around the country has led to organisations such as Surfers Against Sewage setting up interactive UK sewage pollution maps that update in real time to warn you where you shouldn't swim if you fancy a dip this summer.

Dirty water threatens human, animal and ecosystem health. Starting with the obvious, E Coli and other bacteria found in raw sewage can make people very unwell. As well as that, algal blooms from eutrophication suffocate fish and other water life, while microplastics and 'forever chemicals' like PFCs creeping into our ecosystems can cause a raft of health problems, including long-term genetic, hormonal and reproductive changes in animals and people.

Here are three big reasons for the current state of our waterways.

1. Human sewage pollution

'54% of river stretches failed because of activities attributed to the water industry (including treated and untreated sewage discharge, and abstraction of groundwater)' – State of our Rivers report, The Rivers Trust 2024

Data from the Environment Agency shows that in 2023, there were 464,056 sewage discharges into English rivers, waterways, and seas. That's an average of 1,271 sewage spills per day, and a 54% increase on the year before.

*Data from the Environment Agency. The number of overflows recording data also increased over this period from 12,092 to 14,031

Water companies are legally allowed to discharge untreated sewage into waterways at times when the sewerage system is being overwhelmed. 

In practice, this should equate to times when there is heavy rainfall and the sewers potentially can't cope with the extra rainwater running into drains. Storm overflows (also known as combined sewage overflows - CSOs) are designed to stop sewage backing up and flooding people's homes and streets; a necessity of a sewerage system. 

Water companies monitor the frequency and duration of these 'overflow events' using event duration monitoring (EDM). The number of monitored storm overflows has increased rapidly in recent years and now 100% of overflows are monitored.

You can view a map of where sewage spillages have occurred on the Rivers Trust website.

Why is sewage overflowing so much?

While some of the increase in reported incidents can be chalked up to increased monitoring, this isn't the only explanation. 

Other reasons for an increase in occasions where storm overflows are used include:

• Increased population and 'urban creep' Urban changes such as more building developments, as well as the paving over of patios, the use of artificial grass, or the building of extensions into gardens, all come together to reduce the ability of the ground to soak up rainwater naturally. It runs over impenetrable surfaces like concrete and tarmac and passes into combined sewers instead. 

• Climate change has also led to increased rainfall in the UK. 2023 was a particularly wet year, so part of the increase in sewage spills can be attributed to this. As can be seen from the table above, 2021 and 2022 had fewer spills, some of which is attributable to drier weather.

• A lack of investment in our old water infrastructure to cope with both of the issues above. In addition, water companies need to invest in nature-based solutions to help environments to be better able to cope with floods. This can include allowing water to soak into the ground, redirecting water flow, storing water or slowing down its flow.

Water companies also face a lack of trust from the public. Prominent recent investigations by organisations such as the BBC and Surfers against Sewage have raised suspicions that water companies may be using the sewage overflows on dry days – they are only supposed to use them in times of heavy rainfall. In response, many water companies disputed the findings of these investigations.

Ofwat (the Water Services Regulation Authority) is currently investigating whether water companies are treating as much raw sewage as they should.

In March 2022, Ofwat opened enforcement cases into five companies, but all water and wastewater companies in England and Wales remain subject to its ongoing investigation.

2. Agricultural water pollution

'62% of river stretches failed because of activities attributed to agriculture & rural land management (pollution from fertiliser or livestock)' – State of our Rivers report, The Rivers Trust 2024

It's important to note that when looking at the mammoth task we face in cleaning up our waterways, human sewage and its associated infrastructure isn’t the only issue. Agriculture is actually responsible for a larger proportion of river damage.

Manure spread on farmland from animal agriculture is the route by which many pollutants end up in waterways.

A recent report from Sustain and Friends of the Earth found that nine major meat and poultry firms produce more than 30,000 tonnes of livestock waste a day – to use the age-old comparator, that's the equivalent of 1,700 double decker buses. 

Chicken and dairy farms are particularly linked to agricultural water pollution.

Campaigning organisation Compassion in World Farming (CIWF) recently carried out an investigation into the number of new 'mega factory' farms that have appeared in the UK since 2016. It found they have increased 20% in this time period. 

CIWF has used its data to create a map of the UK showing the areas with the highest concentration of factory farms. Its methodology only includes chicken and pig farms, as dairy and beef farms aren't required to define themselves as intensive based on their number of animals.

Manure pollution in the River Wye

In particular, agricultural pollution in the River Wye has been covered widely in the media. Campaigners say it is at the point of ecological collapse, and that the majority of the pollution comes from phosphates running off the local land.

Much of this phosphate comes from chicken manure – it has the highest phosphate levels of any animal manure. In recent years intensive chicken farms have exploded in numbers in Herefordshire and the Wye area. 

The number of chickens farmed in England and Wales is rising at a rate of a million birds per month. There are currently approximately one billion birds farmed per year in the UK.

In areas of intensive animal production, this means there can be too much manure to be dealt with in an environmentally responsible way. To get rid of it, chicken manure is sold to arable farmers who spread it onto the surrounding farmland. From there, it can leach into the river after rainfall.

But why is chicken manure so high in phosphate? A significant factor is their diet. Phosphorus (originally mined in Morocco or the Western Sahara) is used as fertiliser on soy (mainly grown in South America) which is then fed to chickens in intensive indoor systems in the UK. 

Many of the chicken farms in the Wye are owned by one massive agri-business – Avara Foods. The law firm Leigh Day has brought a group legal action against Avara Foods for the damage it believes has been done to the River Wye. It's expected to take several years.

Avara has recently started exporting a large proportion of its manure out of the area, instead. Some will be sent to anaerobic digestion but some will be spread on agricultural land elsewhere. Campaigners argue that this is simply shifting the problem to new locations.

The Soil Association's 'Stop Killing Our Rivers' Campaign says the only real solution is to farm and consume 'less and better' chicken and move away from intensive chicken production completely.

Though they aren't tracked by the CIWF data, dairy farms play a part too. An Environment Agency report into the problematic state of the River Axe in Devon found that of the 86% of local farms visited, 95% failed to pass Silage, Slurry and Agricultural Fuel Oil regulations.

The Environment Agency has been allocated extra budget to conduct more farm inspections and the DEFRA is trying to incentivise farmers to reduce runoff, protect watercourses and improve slurry storage.

3. Chemical and plastic pollution

Waterways aren't just subject to the perils of sewage and manure. Chemicals washed into them, either from working their way into the land or via sewers, can have serious effects on wildlife and human health.

Even when water is treated at treatment plants, the system isn't designed to treat all of the vast array of chemicals that we use (and wash away) in modern life.

Our wastewater contains pharmaceuticals, forever chemicals such as PFAS/PFCs and microplastics, not all of which are currently monitored by the Environment Agency. 

Forever chemicals can have effects on hormones, immune systems and have been linked to several cancers in humans. The long-term effects of microplastics in our ecosystems aren't yet fully understood, but they are known to have damaging effects on wildlife.

These chemicals can be bio-accumulative too – the Rivers Trust's recent analysis of government data found that in some sections of rivers, levels of forever chemicals in freshwater fish were now 1,000 times the safe level. 

The Royal Society of Chemistry released a report in 2023 that found over a third of water courses tested in England and Wales contained medium or high-risk levels of some types of PFAS.

Our rivers, seas and lakes are also polluted by solid items that are flushed down the toilet, such as wet wipes, and litter that we drop on land that makes its way into our water.

According to the Helmholtz Centre for Environmental Research, 90% of the plastic polluting our oceans comes from 10 rivers around the world.

Plastic-containing wet wipes are set to be banned by the end of the year. But the plastic-free ones can still cause problems by blocking drains and failing to effectively break down. 

Don't flush any wipes down the loo – the Fine to Flush certification has been scrapped because of these concerns.

What can you do?

To avoid sewage pollution, it's advisable that you don't swim in the sea or in designated river swimming spots for the 48 hours after any significant rain. Not only are sewage overflows likely to have been used, but agricultural runoff significantly increases when there's heavy rainfall.

You can check for real-time sewage alerts using the Surfers Against Sewage UK pollution map.

When it comes to your household drains, The Rivers' Trust advises:

• Don't flush anything apart from loo paper down the toilet. 
• Don't put oil and fat down the sink, as this can cause blockages. 
• Avoid using household cleaning products and other chemicals that are 'hazardous to aquatic life'.
• Don't abrasively scrub away at non-stick pans - these can be significant sources of PFAS/PFCs.
• Avoid covering your outdoor spaces with hard paving or artificial grass – even a small amount of grass or soil can help reduce the flow of run-off water to your local rivers and reduce pressure on drains during heavy rain. 
• Avoid using chemical fertilisers and pesticides in your garden.

Reducing water use and leaks also helps reduce pressure on our rivers:

• Go for low-flush options for your toilet, an eco shower head and fix dripping taps in your bathroom.
• When it comes to upgrading kitchen appliances, choose water-efficient options. Which? has Eco Buy recommendations for appliances such as washing machines and dishwashers
• Eat local and seasonal food and reduce your meat consumption as meat generally has a higher water footprint than cereals and vegetables.
• Get a water butt to collect rainwater to water your garden if you can and choose plants that are drought resistant if you live in an area prone to drought. Adhere to hosepipe bans.

Water bills are going up by an average of £94 in England and Wales over the next five years. See how much bills are set to increase and get our advice on how to reduce your water bills in our guide to water bill price hikes.