“Nutrient neutrality” rules which have held up thousands of homes across east Kent will be scrapped if the Conservatives win the election, the party’s manifesto announced.

But the plans are already proving controversial with both developers and environmentalists. Here, reporter Dan Esson looks at what is being proposed and how it could impact protected areas in the county…

Nutrient neutrality regulations - what are they?

In 2018, an EU court ruled that mitigation for changes in the nutrient levels of water from development can’t be postponed into the future.

However, despite leaving the EU, the UK has retained these regulations in the form of guidance from Natural England - a public body backed by the Department for Environment, Food and Rural Affairs (Defra).

The nutrient neutrality rules are intended to make sure that building new homes does not alter the fine balance of chemicals in protected bodies of water - such as Stodmarsh nature reserve near Canterbury - in a way which will damage the ecosystem.

Natural England has told 74 local authorities throughout the country they need to observe these regulations in planning decisions.

In practice, the strict rules have resulted in thousands of proposed new homes being held in planning limbo - officially given permission but not allowed to be built until permanent solutions are found to nutrient neutrality.

How have they affected Kent?

Nutrient neutrality rules around the Stodmarsh nature reserve have held up a number of developments across swathes of east Kent, covering parts of the districts of Ashford, Canterbury, Dover, Folkestone, Thanet and Maidstone.

These include the long-planned works on the vacant Debenhams and Nason’s buildings in Canterbury, and the plans for multimillion-pound film studios and homes at Newtown Works in Ashford.

What has the government done about the rules?

Previously, the government had announced it would ease the backlog of planned new homes by allowing developers to apply to purchase “nutrient credits” for mitigation such as new wetlands.

The Conservatives officially committed to seeing 300,000 homes a year built in England by the “mid-2020s” in their manifesto for their 2019 election victory.

However, in 2023 only 231,100 were built, and Britain has not built anywhere close to 300,000 since the 1970s, with 290,000 built per year from 1969-1972.

The government later announced it would completely do away with the neutrality rules and instead double its investment in Natural England’s nutrient mitigation scheme - giving the body £280 million.

This involved developers creating new wetlands and woodlands to “soak up” - or mitigate - unavoidable pollution from the building of new homes.

But the new Conservative manifesto released on Tueday makes no mention of investing further in Natural England’s scheme.

Instead, it commits to “abolishing the legacy EU ‘nutrient neutrality’ rules to immediately unlock the building of 100,000 new homes with local consent, with developers required in law to pay a one-off mitigation fee so there is no net additional pollution”.

If the change was implemented, it would theoretically mean that thousands of homes across Kent could start being built, and the granting of planning permission for new houses would be sped up.

The Labour Party’s manifesto says: “We will implement solutions to unlock the building of homes affected by nutrient neutrality without weakening environmental protections.” It provides no further detail.

What do environmentalists think?

Dr Hilary Newport, director of the Campaign to Protect Rural England (CPRE) Kent, says the Conservatives’ proposals are “absolutely not” the way to tackle the housing crisis.

“It's a way of getting more mass building of substandard properties, if that’s what you want - but I think in a civilised society we can do rather better than that in the 21st century,” she said.

Dr Newport says the Stodmarsh nature reserve is “a very protected area”.

“It has some of the highest levels of environmental designation. It’s an internationally important wildlife site because it houses so many migratory fowl,” she said.

“It is a very, very rare habitat – chalk streams are about as rare as the Amazon rainforest.

“Britain has almost all of the chalk streams and they are universally now so polluted that they are just a shadow of their former selves.”

Dr Newport argues that in theory the rules could be changed in a way without leading to further pollution, but adds: “Simply making it a payment for nutrient neutrality is not paying sufficient respect to the natural environment, which is too important.

“East Kent is massively overdeveloped as it is - it’s sucking people out of London to come to an area that’s strapped for resources and infrastructure, but that’s probably a different policy topic.”

What do developers think?

Ben Geering, head of planning at local development giant Quinn Estates, is also critical of the plans, but for very different reasons.

“Our feeling is that this is an election pledge, like many others, that promises something that should have already been resolved and could have already been addressed,” he told KentOnline.

“The government has had more than four years to introduce primary legislation that removes the requirement for nutrient neutrality to be achieved.

“They have not managed it yet, nor set out how the mitigation tariff would be lawful nor what the mitigation funded by the tariff would be and how it would be delivered.”

Among the developments held up by the Stodmarsh concerns is the 725-home ‘Large Burton’ estate in Kennington, Ashford.

To combat this, Quinn Estates, partnering with Redrow, engineered a new £3.5 million wetland on a neighbouring site to filter out excess nitrates and phosphates from entering the River Stour.

Mr Geering said: “The housebuilding industry and others have innovated, at huge cost, to deliver nature-based solutions that achieve neutrality. The suggestion of new legislation, without a timeline for delivery, puts this innovation at risk.

“The outcome of this announcement could therefore be a pause on investment in mitigation projects, further slowing down housing delivery before any changes in legislation are in place.”

In the same section of their manifesto, the Conservatives express their “cast-iron commitment to protect the green belt”, which Mr Geering is also critical of.

“It is also disappointing to see the government doubling down on additional protection to the green belt, when significant evidence shows that the green belt has grown year on year, that protecting the green belt is leading to increased development elsewhere and that appropriate green belt release is essential to meeting housing need,” he added.