Biodiversity Net Gain

The Environment Act 2021 introduced a new requirement for a biodiversity net gain to be demonstrated for certain types of development which are the subject of planning applications.

For major development (unless otherwise exempt ) biodiversity net gain went live for planning applications made on or after 12 February 2024; while for smaller sites (unless exempt) the date was 2 April 2024.  These requirements do not apply retrospectively for applications submitted prior to these dates.

Biodiversity net gain (BNG) is an approach to development, and land management, that aims to leave biodiversity in a better state than it was beforehand. This is measured through the use of the statutory Biodiversity Metric. 

There are also new requirements to submit BNG information with development proposals in order to allow the council to validate applications.  You should therefore familiarise yourself with the guidance published by Government. 

Some of the key points to be aware of are set out below:

  • There are some exemptions to this requirement – this includes householder applications, development impacting habitat below a set ‘de minimis’ threshold, and small scale self-build and custom housebuilding. Planning application forms have been updated to include space to explain why you think your proposal is exempt.
  • A minimum 10% gain will be required to be demonstrated using the Biodiversity Metric.
  • Habitat improvements will need to be secured for at least 30 years. This can be delivered through a combination of on-site and off-site measures, or via a statutory biodiversity credit scheme. Any off-site measures will need to be included on a BNG register administered by Natural England. The Biodiversity Metric will account for the location of habitat relative to the development site, alongside other factor such as the habitat size, condition, distinctiveness and strategic significance.
  • There will be some scope to ‘stack’ and ‘bundle’ BNG with other requirements, such as nutrient mitigation.

The government is publishing guidance and resources in relation to BNG at: https://www.gov.uk/government/collections/biodiversity-net-gain