Biodiversity Net Gain

Biodiversity Net Gain is a way of creating and improving natural habitats.

What is Biodiversity Net Gain?

Biodiversity Net Gain is an approach to improve the sustainability of development. It makes sure development has a measurably positive impact (‘net gain’) on biodiversity, compared to what was there before.  

Biodiversity Net Gain measures the biodiversity of a site using the Defra Biodiversity Metric, which follows the mitigation hierarchy of ‘avoid – mitigate – compensate’. It assesses the impact of development and aims to create new habitats as well as enhance existing ones.

The Environment Act 2021 requires a minimum of 10% net gain for all major development and small sites, unless your proposal is listed under the exempt developments criteria.

Developments must achieve this net gain within 30 years and manage and monitor the net gain site for this period.

Applicants should refer to the BNG Planning Practice Guidance when considering their application.

Biodiversity technical advice note

We have produced a biodiversity technical advice note which details our approach to Biodiversity Net Gain, including validation requirements and how to provide on-site and off-site Biodiversity Net Gain. 

The current Biodiversity Net Gain planning requirements for major development are:

  • submission of latest version of Biodiversity Metric
  • submission of Biodiversity Gain Plan or statement
  • demonstrate 10% Biodiversity Net Gain

Applications should continue to make provision in line with policy NBE4 of the Hart District Council Local Plan April 2020 and meet the validation requirements detailed in the biodiversity technical advice note.

This includes the submission of the latest DEFRA metric, and a plan showing how on-site net gain shall be achieved, or a statement detailing the intention to purchase off-site credits where necessary. 

See the planning validation requirements for further details on submission requirements.

Forthcoming changes

Minor developments will soon need to use the recently released Small Sites Metric. We will publicise the introduction through this webpage and through validation updates.

Additional guidance

Is this page helpful?

Is this page helpful?
Last reviewed: