What is happening?

From 12 February, applicants for planning permission will, in most cases, have to submit a biodiversity plan as part of their planning application. This biodiversity plan will set out how the post-development biodiversity value will exceed the pre-development biodiversity value by at least 10%. This increase in biodiversity value is known as Biodiversity Net Gain (or BNG).

Why is BNG being introduced?

The Government Guidance sets out that ‘BNG is a way of creating and improving natural habitats. BNG makes sure development has a measurably positive impact (‘net gain’) on biodiversity, compared to what was there before development.’

Does it affect all developments?

Not all developments will be subject to BNG from 12 February.

Those that will not include:

  • ‘Small sites’, for which the requirement will not be introduced until 2 April 2024.
  • Nationally Significant Infrastructure Projects – BNG won’t apply until 2025.
  • Planning applications which are not made under the TCPA - Regulations will be needed to make BNG apply to these.
  • Developments which do not impact an onsite priority habitat (as set out in a list published under section 41 of the Natural Environment and Rural Communities Act 2006) where the impact of the development will be minimal.
  • Householder applications.
  • Planning permissions in relation to high speed railway transport networks.
  • Biodiversity gain sites.
  • Self-build and custom build applications.

What do you need to do?

Whether you are a developer, landowner, or local authority, you could be affected by BNG.

Local authorities will have already put measures in place to plan for BNG, and to ensure that its delivery ties in with other policies, for example around health and well-being. They will also have considered how BNG requirements are included in local plans.

Unless their development is exempt from BNG, developers will, from 12 February, need to attach a metric tool calculation, showing the site’s biodiversity value before development, to the planning application. Information as to how the BNG requirement will be met (for example, on-site, or off-site) will also need to be provided. The Local Planning Authority must approve the biodiversity gain plan before development is started.

Owners of land which could be used to provide off-site BNG may want to consider assisting developers to meet their BNG obligations. However, careful consideration must be given to dedicating land to this, particularly given that the obligations that they would enter into would last for 30 years.

TLT has a team dedicated to BNG and has experience in advising local authorities, developers, and landowners. If you would like to discuss your requirements, please get in touch.

This publication is intended for general guidance and represents our understanding of the relevant law and practice as at January 2024. Specific advice should be sought for specific cases. For more information see our terms & conditions.

Written by

Katherine Evans

Katherine Evans

Date published

31 January 2024

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