A route to nitrate neutrality for the Solent

Surveying for seagrass on the Solent coast © Lianne de Mello

The Wildlife Trust has put forward a scheme which could see nitrate pollution in the Solent reduced, with added benefits for local people and wildlife.

What's the issue?

No homes can be built in South Hampshire. Natural England's decision to halt any development which would contribute to nitrate pollution in the Solent, follows recent European Court of Justice rulings on the issue.  The existing high levels of nitrates are causing harm to the ecosystem and failure of environmental standards.

Nutrient overload creates vast mats of algae over the Solent’s mudflats, stopping oxygen getting through to the animals in the sediment and causing mass mortality, especially in hot weather. Algae also forms a barrier to many birds which rely on probing the mud or picking off tiny invertebrates from its surface. Lastly, these mats can smother some of our most special yet threatened habitats: seagrass beds and saltmarshes, choking them to death and risking erosion.

Whilst nitrate pollution arises from a number of sources, including in particular agricultural run-off and outfalls, new occupied dwellings would add to the pressures through the waste water generated.

The Wildlife Trust supports Natural England's decision to protect our precious marine environment.  In the longer term, we would like to see far broader action to tackle the diverse causes of pollution, as well as the upgrade of water treatment works to ensure that all sewage is treated to the highest standards before it is released into local water bodies. If any new houses are to be built, measures are needed to ensure that overall pollution levels are reduced.

The solution

The Trust is proposing that land which is currently releasing nitrates in the catchment, such as fertilised arable land, could be managed differently in order to reduce nitrate pollution entering water-bodies, reducing the amount of nutrients ultimately reaching the Solent. 

We have shaped a scheme which would remove lower-grade agricultural land from intensive production (that which is less suitable for growing crops), stop the application of fertilisers and create natural habitats, such as traditionally grazed meadows, wetlands or woodlands.

Natural England has established a method for calculating the nitrogen impacts of new developments and can therefore ensure nutrient neutrality is achieved for any development through the acquisition and restoration of sufficient land.

In addition to the direct nitrate balancing, the proposed scheme has the potential to deliver a number of additional water quality and biodiversity benefits, through wider pollution reduction and expanding and enhancing vital wildlife habitats.

Commenting on the scheme, Debbie Tann, Chief Executive of Hampshire & Isle of Wight Wildlife Trust said: “Our local seas are being suffocated by untenable levels of pollution and we have to find ways of reducing the levels of nitrates entering the Solent.  By taking the most polluting land and re-wilding it, not only are we relieving the pressure on our marine environment but we will also create wonderful wildlife-rich habitat, capturing carbon and helping nature to recover.  We must now ensure that we are creating great places for both people and wildlife to live and thrive.” 

Supporting development that is good for nature

The Trust will work in collaboration with Natural England, local authorities and developers to provide this solution, as long as the proposed housing meets all other requirements, especially biodiversity protection and enhancement.

We are actively advocating sustainable development and net gain for nature. We are concerned that if a solution to this problem is not found, central Government may penalise local authorities by adding additional housing numbers to their already weighty local targets.

We continue to voice our concerns about unsustainable housing numbers in some areas and continue to object to the most damaging proposals.  The Trust is not opposed to all development, only that which fails to give back more to nature than it takes away. 

How to find out more

The Trust is ready to deliver a simple natural solution to this pressing local issue.  We believe that we can substantially reduce pollution and create extensive new areas of natural habitat where wildlife can thrive.

If interested in discussing this scheme further please contact nitrates@hiwwt.org.uk 

Frequently Asked Questions

What’s the problem?

No homes can be built in South Hampshire and the North of the Isle of Wight. Natural England's decision to halt any development which would contribute to nitrate pollution in the Solent, follows recent European Court of Justice rulings on the issue.  The existing high levels of nitrates are causing harm to the ecosystem and failure of environmental standards. 

Nutrient overload creates vast mats of algae over the Solent’s mudflats, stopping oxygen getting through to the animals in the sediment and causing mass mortality, especially in hot weather. Algae also forms a barrier to many birds which rely on probing the mud or picking off tiny invertebrates from its surface. These algae mats can also smother some of our most special yet threatened habitats: seagrass beds and saltmarshes, choking them to death and risking erosion. 

Whilst nitrate pollution arises from a number of sources, including in particular agricultural run-off and outfalls, new occupied dwellings would add to the pressures through the waste water generated.

What is the Wildlife Trust’s involvement?

The Wildlife Trust supports Natural England's decision to protect our precious marine environment.  In the longer term, we would like to see far broader action to tackle the diverse causes of pollution, as well as the upgrade of water treatment works to ensure that all sewage is treated to the highest standards before it is released into local water bodies. If any new houses are to be built, measures are needed to ensure that overall pollution levels are reduced.

The Trust is proposing that land which is currently releasing nitrates in the catchment, such as fertilised arable land, could be managed differently in order to reduce nitrate pollution entering water-bodies, reducing the amount of nutrients ultimately reaching the Solent. 

We have shaped a scheme which would remove lower-grade agricultural land from intensive production, stop the application of fertilisers and create natural habitats, such as traditionally grazed meadows, wetlands or woodlands.

Natural England has established a method for calculating the nitrogen impacts of new developments and can therefore ensure nutrient neutrality is achieved for any development through the conversion and restoration of enough land.

In addition to the direct nitrate balancing, the proposed scheme has the potential to deliver additional water quality and biodiversity benefits, through wider pollution reduction and expanding and enhancing vital wildlife habitats.

Why are you supporting house building?

Our priority is nature’s recovery. We recognise that more homes may be needed but we want to make sure that development is sustainable and gives back to nature more than it takes away.  This means that targets for new housing should be appropriate for the area, planning should be long-term and should have the Nature Recovery Network at its heart – ensuring that important wildlife habitats are protected and enhanced.  In addition, every building project should deliver ambitious ‘net gain’ for nature. 

We are willing to work with local authorities and developers, as long as they can demonstrate clearly that they are meeting their regulatory requirements with regards to biodiversity.  We will continue to challenge both policy makers and house builders to secure the best outcomes for wildlife and people.

Does your scheme give a green light to more pollution through additional housing?

The scheme will ensure that there is less nitrate pollution entering the Solent estuary. The nitrogen input from any new houses will be more than compensated for by taking polluting arable farmland out of production and stopping the use of fertilisers.  In addition to reducing the nitrate pressures on watercourses and the marine environment, the reduction in fertilisers will also lower phosphate levels. By restoring natural habitats, we will lock carbon away and create more space for wildlife to thrive. 

Where will the houses be built?

Any new developments will go through normal planning application process.  The local authority will grant permission for new houses according to their own policies or local plans and subject to all other usual regulatory requirements.  Housing could be located anywhere within the Solent catchment area.  

Will this allow inappropriate housing?

No, nitrate neutrality is an additional condition imposed by Natural England, following a recent ruling from the European Court of Justice.  Housing must meet all other legal and regulatory requirements as well as demonstrating nitrate neutrality.  

There is a risk that if local authorities are unable to find a solution to the current nitrate problem, appropriate planning process could break-down, resulting in inappropriate developments being permitted or additional housing targets being imposed by central government. 

The Trust will continue to oppose planning policies and/or proposed developments that we feel are inappropriate and damaging.  

Are you going to profit from this scheme?

Through a nitrate credit scheme, agreed with Natural England, developers will be able to pay the Wildlife Trust to secure and manage low-quality arable farmland, stop the application of fertilisers and create vibrant natural habitats such as wildflower meadows, woodlands or wetlands.  The cost of ‘nitrate credits’ will include funding for management of the land ‘in perpetuity’ (defined as a minimum of 80 years).  This scheme will enable the Wildlife Trust to move towards its strategic goal of creating more space where wildlife can survive and thrive, as well as reducing the pressures on the wider landscape and seas.   

Why not buy the land anyway and reduce the nitrate pollution even more?

The Trust is a not-for-profit charity and is always looking for new opportunities to secure more space for nature. You may have seen recent public fundraising appeals to help us buy additional sites that are vital for our local nature recovery network.  Making existing farmland wilder through this nitrate neutrality scheme is an exciting opportunity not just to reduce pollution but to expand the network and help nature’s recovery across Hampshire and the Isle of Wight. 

Shouldn’t the Trust be pushing for a drop in pollution not just ‘nitrate neutrality’?

Absolutely. The scheme factors in a 10% reduction in nitrate levels to help reduce the harmful eutrophication that damages the estuary. The reduction in fertiliser will also lead to reduction in phosphate pollution, carbon sequestration and significant biodiversity gains.

Will this scheme be bad for farmers?

Over 70% of Hampshire is farmed. We know that many farmers are already seeing the benefit of farming with nature and the Trust is proud to work positively with the agricultural community across the counties.  The land associated with this scheme represents a very small fragment of low-quality arable and will not have a negative impact on farming in the area.  

Will this take valuable farmland out of food production?

The Trust is prioritising purchasing lower quality farmland that has less agricultural potential than other areas. Low quality farmland often has significant fertiliser loads added with limited productivity potential. Using this small portion of land represents a chance to make a great space for nature without compromising high quality farmland .

What will you do with the land?

The Trust will manage the land to produce highly biodiverse wildflower meadows, wetlands and woodlands filled with life. This means that the scheme will not only reduce pollution but will also help to absorb carbon and support local wildlife recovery.