Biodiversity Net Gain

Biodiversity Net Gain

Biodiversity is the variety of all living things on our planet, from species to habitats and ecosystems. It is a form of natural capital that helps to create and maintain our eco-system services.

Biodiversity Net Gain (BNG) is an approach to planning, developments and land management that aims to leave the natural environment in a measurably better state than it was beforehand. It is intended to deliver measurable improvements for biodiversity by retaining, creating or enhancing habitats.

From 12 February 2024 all major developments in England will have to deliver 10% BNG and from 2 April 2024 all developments (except for some exceptions, such as householder applications) will have to deliver a minimum 10% BNG under the Environment Act 2021 calculated using the Statutory Metric. Developments must achieve this net gain within 30 years.

This requirement does not replace, but is in addition to, the existing policy and legal requirements related to biodiversity and development.

To measure BNG and assess the impacts of planning applications Defra’s Biodiversity Metric (or for smaller sites the small sites metric) should be used.

Biodiversity Net Gain: Good Practice Principles for Development (published by CIEEM) should be followed when designing developments and preparing planning applications. Biodiversity net gain sets out 10 ‘Good Practice Principles for Development’ which must be applied all together, as one approach. Further advice can be obtained from the council via our pre-application advice service.

Planning applicants will need to provide information on the biodiversity value of their application site and how they plan to deliver 10% BNG as part of their application.

In most cases, BNG should be provided on the development site (particularly where proposals impact designated sites, irreplaceable habitats or priority habitats), but in some cases, and in agreement with the council, it may be necessary to provide the net gain off-site. This could be on land within the planning applicant’s control or via another landowner or BNG broker.

Government guidance on the BNG process is available at:

• Developer guidance

This is also in accordance with Policy NAT1 (Biodiversity, Geodiversity and Important Natural Features) of the Tewkesbury Borough Plan.

Further site/project specific input can be provided via our pre-application service.

Mitigation Hierarchy

The requirement for Biodiversity Net Gain does not alter existing requirements and protections in planning policy and legislation for the natural environment such as protecting importance habitats and species. It maintains and reinforces the mitigation hierarchy, which is embedded in national planning policy (NPPF paragraph 180). Gains in biodiversity should initially be achieved on-site (within the proposed development site), avoiding impacts first, then minimising and mitigation, and compensation for losses as a last resort. If compensation for losses on-site is not possible, as a last resort, biodiversity losses should be sought off-site.

Ideally, BNG should be delivered:

• on-site, through habitat creation/enhancement via high quality landscaping and green infrastructure provision, but can be delivered;
• off-site through habitat creation/enhancement, including via habitat banks and with public and private landowners preferably in the local authority area.
• if local off-site BNG delivery is not possible, the last resort option is to buy statutory credits from the government.

Gloucestershire Local Nature Recovery Strategy and BNG

Local Nature Recovery Strategies are spatial strategies introduced by the Environment Act 2021 which aim to guide nature restoration to contribute to the expansion of the Nature Recovery Network across England. The strategies help to understand where nature recovery actions in the area would be most effective and will make the greatest collective impact for biodiversity. The Gloucestershire Local Nature Recovery Strategy [SC5.1](LNRS) establishes biodiversity priorities and maps proposals for actions to push the recovery of nature and improvement of biodiversity across the county. Gloucestershire County Council was appointed by Defra as the Responsible Authority for the Gloucestershire LNRS which was published on the 13th February 2026.

Developers should use the LNRS to design green infrastructure that delivers for people and positively impacts nature and its recovery across the county. The LNRS should also be used by planning applicants when determining how and where to deliver BNG as part of their development, including to inform the location of off-site BNG. Development projects which create, enhance or recover habitat in locations mapped in the LNRS will generate a higher biodiversity value within the metric than they would in other locations which are not mapped within the LNRS. The BNG statutory metric user guides contain guidance on how to assign strategic significance for habitats in the biodiversity metric using the LNRS.

Planning applicants should refer to the relevant guidance for BNG to ensure that the LNRS and strategic significance have been appropriately considered and recorded within their BNG proposals prior to submitting their application to the local planning authority. Further information published by Local Government Association Planning Advisory Service provides guidance on how strategic significance should be recorded after the publication of the LNRS. Guidance documents are periodically updated to reflect changes in national and local legislation, policy and guidance.

In conjunction with referring to the LNRS, applicants may need to consult with an ecological professional to decide on the most appropriate creation, enhancement or restoration measures or to inform habitat and land management plans. Alternatively, applicants can engage with Tewkesbury Borough Councils pre-application advice service: Get advice on your planning application – Tewkesbury Borough Council.

Planning

Applications should continue to meet the current local validation requirements. This includes the submission of the latest DEFRA Biodiversity Net Gain Metric to confirm how the biodiversity gain objectives of at least a 10% gain will be met for the development. Once planning permission has been granted, a Biodiversity Gain Plan must be submitted and approved prior to the commencement of development.