What is nutrient neutrality and why is it important for developers?

In March 2022, the Government took a number of steps in relation to the environmental issue of nutrient pollution which, whilst important for the Government’s commitment to the environment, have a significant immediate impact on the planning system in affected areas.

England has a number of “protected sites” – these include nature reserves, wildlife sites, geological sites and Local Planning Authorities (LPAs) are obliged to consider whether any  proposed development is on, or might affect, any protected sites when considering planning applications or policy and plan making.

What is nutrient pollution and why is it a problem?

Nutrient pollution is in essence the increase in levels of nutrients such as nitrogen and phosphorous.  Nutrient pollution is a particular problem for freshwater habitats and estuaries as increased levels of nutrients can impact any wildlife that live there.  Ultimately, nutrient pollution is a significant risk for a number of protected sites.

As a result of the relevant environmental regulations and case law, Natural England previously advised 32 LPAs that, where protected sites are impacted by nutrient pollution, development must only go ahead if it is “nutrient neutral” i.e. will not add to nutrient pollution.

Natural England has now identified a further 20 protected sites which may potentially be impacted by nutrient pollution.  Consequently, Natural England has advised a further 42 LPAs that they must consider possible nutrient pollution as part of a Habitat Regulations Assessment when reviewing any planning application.  LPAs must be confident that the development in question does not need to be nutrient neutral to be acceptable under the relevant regulations or that nutrient neutrality is secured as part of the proposal.

How are Local Planning Authorities impacted by neutrality issues?

The number of LPAs impacted by neutrality issues has therefore more than doubled from 32 to 74.  Locally impacted LPAs include Maidstone Borough Council, Ashford Borough Council, Canterbury City Council and Swale Borough Council, but this is a nationwide issue.

This could significantly impact the approval of planning applications by the LPAs and also have cost and time implications for developers in affected areas – the Government has advised that they may need to reconsider the acceptability of current proposals, obtain further information from applicants and re-consult on those applications.  As a result, decisions on planning applications have paused across a number of LPAs.

In addition, there is uncertainty as to the way in which LPAs assess whether or not a development is nutrient neutral and what evidence developers need to provide to demonstrate this.

How can the causes of nutrient pollution be reduced?

New wetlands, buffer zones to provide woodlands, new spaces and grasslands are methods of reducing the causes of nutrient pollution.  However, if an area has recently been added to the list of impacted areas, it is unlikely for mitigation solutions such as these or other solutions to be in place already.

How are the Government helping nutrient pollution issues?

The Government is looking to offer clarity and assistance with nutrient calculators, and investment in staff dedicated to advising on mitigation measures.  However, the Government has itself recognised that the ability for development to be permissible will necessarily be limited in the short term and that it will take time for applicants to secure mitigation and be able to demonstrate neutrality.  Furthermore, this advice may be challenging in relation to plan making.  The Government has stated that the approach adopted by currently affected LPAs has been complex, time-consuming and costly to apply.

How are developments being impacted by nutrient pollution?

In Kent, large scale developments in Ashford and Canterbury have recently stalled whilst developers secure land and propose schemes to create new offsite wetlands as a mitigation method to demonstrate nutrient neutrality.

On smaller scale developments, applicants may need to consider options such as on-site Sustainable Urban Drainage Systems, improvements to package treatment plants or septic tanks.  Alternatively applicants may be asked to make financial contributions to authority-wide mitigation measures.  However, as noted above, the exact extent of the required mitigation and/or mitigation options may be unclear for newly impacted areas.

Whilst the commitment to environmental protection and reducing pollution is welcomed by many, including environmental bodies, this issue could potentially cause a significant amount of uncertainty for LPAs and developers alike, ultimately impacting on the cost and time in delivering development in line with demand from both purchasers and Government requirements.