Nutrient Neutrality Guide

Developers need to offset the additional nutrient pollution caused by new developments within protected areas.  They cannot get planning permission without doing this.  They can either purchase Nutrient Credits or create Nutrient Mitigation Schemes themselves. 

Greenshank Environmental develops wetlands and other innovative schemes to provide nutrient offsets in areas affected by Nutrient Neutrality. The nutrient offsets our schemes create become nutrient credits that can be used by developers to offset the additional nutrient pollution caused by new developments within protected areas. Our expert team has been behind some of the UK’s first nutrient mitigation projects for Nutrient Neutrality, including phosphorus treatment wetlands in Herefordshire, decommissioning industrial sites, in Hampshire and taking agricultural land out of production in the Solent. We have experience advising regulators and Local Planning Authorities on the evidence and standards needed to secure nutrients credits with sufficient certainty. We will use this expertise to ensure our mitigation projects will deliver nutrient credits with certainty needed to unlock housing development.     

Nutrient Neutrality is a new legal requirement within the Habitat Regulations with which developers planning new schemes must comply.  This is because nutrient pollution from new building development can damage the rare ecology of protected aquatic ecosystems.  Where sites protected under the Habitat regulations already have unsustainable levels of nutrient pollution, all proposals for new development are now required to show that the new scheme will not make the pollution worse. In other words, the new scheme needs to be ‘nutrient neutral’. Nutrient Neutrality for new developments is delivered by offsetting the nutrients that the new scheme will produce. A key way to do this is  through offsetting schemes such as new  wetlands.  

Nutrient pollution is released into freshwater and coastal areas from a range of different sources, including agriculture, aquaculture, septic tanks, wastewater, urban stormwater runoff, industry and fossil fuel combustion. These nutrient sources can either be carried in water that comes from various sources on land or be deposited from the atmosphere. Although various actions that are have been taken to reduce nutrient pollution, it is still at unsustainable and damaging levels in many protected ecosystems.    

27 areas of England and most of Wales have been impacted by Nutrient Neutrality. In these areas, more than 72 of the UK’s 333 Local Planning Authorities have been affected by Nutrient Neutrality and cannot consent to new development without it showing it is nutrient neutral. Over the next 5 years, the issue will more than double in scale to cover 65 areas and more than 140 Local Planning Authorities.   Nutrient Neutrality hits hardest in areas where there is a lot of planned development. The areas of the UK now facing the largest challenges are:  

England 

The River Tees catchment 

The River Wensum and Norfolk Broads catchments 

The Somerset Levels 

The Solent 

The Hampshire Avon catchment 

The River Eden catchment 

The Derwent and Bassenthwaite Lake catchment 

The River Wye and Lugg catchment (Herefordshire) 

The Poole Harbour catchment  

The River Stour and Stodmarsh catchment   

The River Wye catchment (Derbyshire) 

The River Camel catchment  

Wales 

The River Usk catchment 

The River Dee catchment 

The River Wye catchment  

The River Towy catchment 

The River Cleddau catchment 

The River Teifi catchment 

Most of the mitigation schemes providing nutrient offsets are based on abandoning agricultural land. By stopping farming, you remove a source of nutrients by removing fertiliser or animal manure inputs to the land. This is how development has been unlocked in The Solent region. However, this approach is not cost efficient, has big impacts on the livelihoods of farmers and is problematic at a time when food security is more important than ever. 

Agricultural abandonment schemes also do not work for phosphorus as you need too much land for them to be financially viable, so this approach can only be taken in areas where nitrogen is the only nutrient of concern.   

There are various mitigation options that could be delivered by different types of land management. These options include riparian buffers, engineered logjams and blocking drainage ditches, which collectively are termed as ‘catchment management solutions’. These solutions have relatively low land take, are supported by evidence and are backed by the regulator. We know this as our experts are currently writing guidance for the regulators on how these options could be deployed. 

Catchment management solutions also have a range of extra environmental benefits including biodiversity improvements, natural flood management and carbon sequestration. 

Wetland schemes are another potential mitigation option that can deliver nutrient offsets at scale and without a significant land take, making them  both space- and cost-efficient. These solutions are also supported by a methodology from the regulator.   

Credits are created on an 'offset per year basis' as they need to offset the same amount of nutrients in perpetuity. 

Our wetland projects will deliver nutrient offsets that are quantified as kgs of nitrogen or phosphorus removed from the environment. Each kg of nitrogen or phosphorus removed will be sold as a nutrient credit.  

As credits can only be sold within a very specific catchment area,  credit price is driven by local supply and demand.  In the open market, in areas with high demand, but limited supply there will be significant competition which will drive the price up. 

We have seen prices as high as £100,000/kg, for Phosphorus. Nitrogen credits are typically linked to agricultural offset costs, so much lower.  

We would welcome the chance to speak to developers who are looking to reduce the cost of credits by co-investing in a local scheme with Greenshank.