The Conversation
03 Apr 2025

Once voted the UK's favourite river, the River Wye flows from the Welsh mountains to the Severn estuary - 150 miles through an officially recognised "national landscape". But this idyllic picture is changing, as the river is gradually choked by waste from industrial chicken farming.

The Wye is perhaps the most extreme example, but the nearby River Severn, the UK's longest river, is also at risk, along with rivers in places such as Lincolnshire, Norfolk and Yorkshire.

In the land that feeds into these rivers, millions of chickens are being reared in intensive units to supply supermarkets with cheap meat and eggs. But all those chickens produce vast amounts of manure which can end up in the rivers.

This floods the river with excess nutrients causing algal blooms to flourish. The algae blocks out sunlight and consumes oxygen, which kills other creatures in the water. For instance the number of Atlantic salmon passing through the River Wye each year has plummeted from 50,000 in the 1960s to less than 3,000.

The problems caused by chicken farming have led to legal action against US food company Cargill and its subsidiary Avara Foods (both firms deny the allegations). Meanwhile food outlets including Nando's have denied sourcing their products from polluting farms.

Described as a "dying river" in a Channel 4 News report, in 2023 the Wye's conservation status was downgraded by Natural England to "unfavourable - declining".

Measures to deal with excess nutrients have led to so-called nutrient neutrality policies. These prevent new developments that would cause a net increase in nutrients. But the knock-on effect is that development (including housebuilding) may be blocked.

Much of the River Wye flows through the English county of Herefordshire. There, the council, exasperated by the failure of these plans to reverse the decline, took the unusual step of controlling the pollution through planning laws.

Its Minerals and Waste Local Plan declared that any new chicken farms must demonstrate that the manure would be properly managed and the project would overall be nutrient neutral. That would form part of an environmental impact assessment during the planning process.

This was unusual because agricultural activities are not usually subject to planning control and what you do on your farm is generally regulated by non-planning statutory regimes. So, the step taken by Herefordshire Council was unusual and the National Farmers' Union (NFU) challenged it in court.

What was also new, was the categorisation of manure as "waste".

Agriculture mainly gets a pass on waste controls. Faecal matter (including chicken manure) is not treated as waste in law as long as it does not harm the environment or endanger human health, even though it is not the farmers' primary product. A farmer breeds chickens for meat and eggs but chickens also produce manure. But that manure can still be useful as a fertiliser, for energy or as compost. So far so good. The problem comes when that by-product is not managed carefully and it ends up polluting rivers.

So should it be defined as waste - and therefore subject to strict controls - or treated as a valuable byproduct and managed as a commodity just like the eggs?

The answer is: it depends. Case law indicates that the test for whether the manure would be waste is whether it can harm the environment.

In the High Court case, the NFU argued that agricultural activities should not be subject to planning controls and that manure should not be treated as "waste". In effect its argument was that the economic endeavours of farmers should outweigh the additional environmental protections introduced by the council.

The judge did not agree with the NFU. She said that chicken manure could indeed be waste and the council could control it through the planning regime.

This is a symbolic battle between those tricky pillars of sustainable development: economy, society and environment.

In any planning case, the elements need to be balanced and one will dominate over the others. Housing for people? Industrial development for economic growth? Industrial farming for (cheap) food? Protecting the river and its ecosystem from pollution? Every decision made represents a trade-off.

As the courts move to prioritise protecting the environment, the UK government is favouring economic growth. Its Planning and Infrastructure Bill plans to replace individual environmental impact assessments with broad based "environmental delivery plans" produced by a government body (not the developer) but funded by developers.

These delivery plans will set out conservation measures addressing environmental impacts of development. They might focus on protected species or habitats or on issues like nutrient neutrality.

But there is no shortage of plans already in the government armoury. Environmental Improvement Plans were set up by a previous government. Among these, the Wyescapes landscape recovery project is aimed at developing "sustainable, future-proof business models working with nature along the floodplain". The River Wye nutrient management plan aims to halt nutrient pollution. The River Wye action plan aims to stop the decline of the river system by making the catchment a pilot for transforming how manure is managed.

However, as the judge in the NFU v Herefordshire Council case said, all the evidence demonstrates that these plans have so far failed to stop the decline. This left the council to implement drastic and immediate action.

The NFU is considering an appeal. But the council's win at the high court may be in vain when government proposals outlaw the requirement for individual environmental impact assessments.

It remains to be seen how effective the new government ideas on protecting the environment will be. For now, it appears that anything that blocks development is not a government priority.

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