Biodiversity Net Gain (BNG)

There are some types of exempted development, and certain types of permission where the legal BNG requirement does not currently apply:

• permissions relating to applications made before the date of commencement for mandatory BNG i.e., 12 February 2024 (or for small sites, 2 April 2024) (however please note these will still be subject to the Council’s requirement for BNG set out in local policy).
• section 73 permissions where the original permission which the Section 73 relates to was either granted before 12 February 2024 or the application for the original permission was made before 12 February 2024 (or for small sites, 2 April 2024).
• retrospective planning permissions made under section 73A.
• ‘De minimis’ development that does not impact a priority habitat and impacts an area of non-priority onsite habitat less than 25m², or 5m for linear habitats i.e., hedgerows and watercourses.
• householder applications as defined within article 2(1) of the Town and Country Planning (Development Management Procedure) (England) Order 2015.
• self-build and custom-build development where these consist of no more than 9 dwellings, occur on a site area no larger than 0.5ha and it consists only of self build and custom housing as defined in section 1(A1) of the Self-build and Custom Housebuilding Act 2015.
• biodiversity gain sites - developments undertaken for the purpose of fulfilling the BNG planning condition for another development are exempt.
• permissions granted through a development order under section 59 (includes permitted development rights).
• urgent Crown development (granted under 293A of the Town and Country Planning Act 1990).

Other types of permission that are not subject to the BNG requirement include:

• reserved matters approvals (these are not applications for permission, the BNG requirement is attached to the original outline permission)
• permissions in principle (but the subsequent technical details consent would be subject to the general biodiversity gain condition)

Mandatory biodiversity net gain has not been commenced yet for planning permissions granted through other routes, including local development orders, neighbourhood development orders, successful enforcement appeals and deemed planning permission.

Please refer to the Defra blog for further information on exemptions and transitional arrangements.

The approach to BNG delivery will need to meet various statutory minimum requirements as set out in the primary and secondary legislation, including the need to achieve a minimum 10% BNG and maintenance of these assets for at least 30 years. Every grant of planning permission will be subject to a pre-commencement condition that requires the approval of a Biodiversity Gain Plan before construction commences.

Developers should refer to the planning practice guidance and Defra BNG statutory guidance for further detail on all statutory requirements.

The guidance for the Statutory Biodiversity Metric refers to Strategic Significance being the local significance of the habitat in question. Where a Local Nature Recovery Strategy (LNRS) has been published, you should use the relevant published LNRS to define Strategic Significance.. However, prior to the publication of the Hampshire LNRS applicants should use those areas identified in the adopted Landscape, Biodiversity and Trees SPD as having Strategic Significance. These include Biodiversity Opportunity Areas, Biodiversity Priority Areas and Network Opportunity Areas. These are found in Map 2 in Appendix 5.3 of the SPD.

Applications should be supported by information to enable the Council to make a full consideration as to whether the general condition is capable of being successfully discharged. For developments subject to BNG, the Planning Practice Guidance stipulates a statutory minimum level of information, set out below:

• a statement as to whether the applicant believes that planning permission, if granted, would be subject to the biodiversity gain condition
• the pre-development biodiversity value of the onsite habitat on the date of application (or an earlier date) including the completed metric calculation tool used showing the calculations, the publication date and version of the biodiversity metric used to calculate that value
• where the applicant wishes to use an earlier date, the proposed earlier date and the reasons for proposing that date
• a statement confirming whether the biodiversity value of the onsite habitat is lower on the date of application (or an earlier date) because of the carrying on of activities (‘degradation’) in which case the value is to be taken as immediately before the carrying on of the activities, and if degradation has taken place supporting evidence of this
• a description of any irreplaceable habitat (as set out in column 1 of the Schedule to the Biodiversity Gain Requirements (Irreplaceable Habitat) Regulations [2024]) on the land to which the application relates, that exists on the date of application, (or an earlier date)
• a plan, drawn to an identified scale which must show the direction of North, showing onsite habitat existing on the date of application (or an earlier date), including any irreplaceable habitat

In line with Planning Practice Guidance, the council may request further information at determination stage where necessary to help assist the council in its assessment of BNG proposals in light of existing local policy requirements, and to provide confidence that the BNG objective can be satisfactorily discharged.

The council encourages applicants to engage with its pre-application service to ensure any potential issues are identified, understood and resolved early on in the process, to reduce any future delay and improve the quality of a proposal.

The council is also intending to launch another ‘Call for Green Sites’ later this year, alongside the local plan update process. Landowners interested in putting forward land to deliver biodiversity net gain as a potential source of long-term income are encouraged to engage via this process. Further details will be published soon.

In the meantime we would encourage landowners / landholders looking to deliver a BNG project within the borough to list their site on the Future Homes Hub. This enables any developer seeking local BNG units to identify suitable habitat banks within the borough.