The ‘nutrient neutrality’ issue

In recent years, nutrient pollution (particularly from nitrogen and phosphorous) has become a significant problem affecting a range of river and other freshwater habitats and estuaries. The concern is that increased nutrient levels in excess of safe thresholds that come from new developments find their ways into local watercourses and have a profound impact on the water quality in a wider catchment area.

Special concerns around water quality are focussed on a range of statutory protected designated ecological sites. To comply with Habitat Regulations, local planning authorities in 74 affected areas of England (as identified by Natural England) are required to consider the impact of any proposed development when granting planning permissions. As part of the consenting process, developers must prove that they can achieve nutrient neutrality for their proposals. Where there are already high levels of nutrients, in most instances, mitigation measures will be required.

The requirement for assessing nutrient neutrality (or the absence of it) and agreeing appropriate mitigation is adding significant cost and delay to the development consenting process, bringing some planning application decisions to a halt completely in the affected catchments. To date there has been a high mitigation requirement to achieve the necessary offsetting of nutrient pollution related to development, as well as insufficient availability of accessible mitigation measures.  It has been estimated that some 100,000 new homes have been put on hold as a consequence.

Nutrient mitigation Scheme

The Government has recently announced a new measure, namely the Nutrient Mitigation Scheme ("the Scheme"). This will be established by Natural England and is set to launch in Autumn 2022, when details of the Scheme will be published, albeit there isn't yet clarity as to when it will be up and running. 

The fundamental aim of the Scheme is to provide the house building sector with an immediate solution to "unlock" stalled development proposals by making access to mitigation easier in the short-term and, over time, to reduce the amount of mitigation needed.

The Scheme will create new wetland and woodlands in partnership with green groups and other privately led nutrient mitigation schemes. It is hoped that these new or expanded wildlife habitat sites will also be open spaces and places which will give increased access to nature for people to enjoy whilst providing for nature restoration.

It is anticipated that DEFRA and DLUHC will provide funding to "pump prime" the Scheme and Natural England will work in conjunction with stakeholders to identify mitigation projects in nutrient neutrality catchments.

The Scheme will enable developers to purchase "nutrient credits" which will discharge the requirements to provide on-site mitigation. Natural England will accredit locally based mitigation sites to be delivered through the Scheme, which will then enable local planning authorities to grant planning permissions for developments which have secured the necessary nutrient credits in their catchment.

The launching of the Scheme will build on arrangements that are already being made in affected areas, with landowners setting aside land to be managed more effectively for nature to provide off-set sites.  There are media reports, for instance, that the local Wildlife Trust in the Hampshire and Solent region, which was one of the first to be affected by the Natural England moratorium, has bought mitigation sites and is selling credits to house builders.

These proposals have been announced together with a new measure to impose a legal duty on water companies to reduce nutrient pollution by 2030 through the upgrading of wastewater treatment facilities to the “highest achievable technological levels”.

Recent Updates

Recent hydrological connectivity and water quality modelling work carried out by Dover District Council and reviewed by Natural England, relating to a protected wetland site in Kent, has meant that Natural England has effectively lifted the moratorium against the grant of planning permissions in that area. The work evidenced a very low connectivity between outputs from a particular wastewater treatment plant and the protected site, and therefore concluded that development resulting in new connections to that plant would not have a significant impact on the protected site. As such, no Appropriate Assessment is required for otherwise affected applications. A formal update on Natural England’s advice in relation to the Stodmarsh catchment area is expected, but we may see that the steps taken here could be used as a model for other affected areas.

Elsewhere, the Prime Minister, Liz Truss, has been widely reported as saying that she wants to scrap rules surrounding nutrient neutrality (which derive from EU legislation), in order to reduce the red tape preventing developers securing planning consent. We hope to hear more about that in the coming months, but it is unlikely to be a quick process.

If you are interested in finding out more or need advice for a project, please get in touch with our planning and development team. Christine de Ferrars Green or Caroline Bywater.

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Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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