Biodiversity Net Gain
Biodiversity Net Gain Update for Agents and Developers
You may be aware of biodiversity net gain (BNG). This is an approach to development that aims to leave the natural environment in a measurably better state than it was beforehand.
The Biodiversity Metric is a way of quantifying this. Natural England has published a free biodiversity accounting tool in Microsoft Excel format, which is to be used for the purposes of calculating biodiversity net gain.
It is not the Government’s intention for Local Authorities to produce their own guidance on how to use the Biodiversity Metric and achieve net gain as this will all be set out nationally. We are expecting final guidance to be published this month.
Achieving 10% net gain means fully compensating for losses of habitat on a development site, but then going further so that overall there is a gain in habitat of at least 10% as a result of the development process. The Government is introducing this requirement to help meet its aspiration to leave the environment in a better state than it found it, and to help meet targets for nature recovery required under the Environment Act. Since 01 January 2023, all public authorities have been under a statutory duty to conserve and enhance biodiversity. The main areas of the National Park’s work that help to deliver the Authority’s biodiversity duty are set out in Table 1 of the Authority’s Biodiversity Duty Reporting Update (December 2023). In terms of planning policy, in addition to the NPPF’s requirement for net gain in biodiversity (paragraph 180), Policy SP6 in the adopted Local Plan requires proposals to protect, maintain and enhance features of the natural environment, including habitats and species of biodiversity importance.
1. BNG will be mandatory from 12 February 2024 for major development
Under the Environment Act 2021, all planning permissions granted in England (with a few exemptions) will have to deliver at least 10% biodiversity net gain, using a metric developed by DEFRA that generates a biodiversity value for a site before and after development to demonstrate this. This applies to major development from January 2024 (exact date is due to be confirmed by the Government this month) and minor development from April 2024. Minor development means:
(i) For residential: where the number of dwellings to be provided is between one and nine inclusive on a site having an area of less than one hectare, or where the number of dwellings to be provided is not known, a site area of less than 0.5 hectares.
(ii) For non-residential: where the floor space to be created is less than 1,000 square metres OR where the site area is less than one hectare.
The following types of development will be exempted from BNG requirements:
- Temporary exemption for non-major developments (until April 2024) Defined as development not defined as major development under the Article 2 Town and Country Planning (Development Management Procedure) (England) Order 2015. The exemption will continue to apply to section 73 permissions where the original permission which the section 73 relates to was subject to this temporary exemption.
- Householder development as defined within article 2(1) of the Town and Country Planning (Development Management Procedure) (England) Order 2015.
- Development granted planning permission by a development order under section 59 This includes permitted development rights.
- Development subject to the de minimis exemption – development that does not impact a priority habitat and impacts less than 25 square metres (e.g. 5m by 5m) of habitat, or 5 metres of linear habitats such as hedgerows.
- Self-build and custom build development – development which:
- consists of no more than nine dwellings, and
- is carried out on a site which has an area no larger than 0.5 hectares, and
- consists exclusively of dwellings which are self-build or custom housebuilding as defined in section 1(A1) of the Self-build and Custom Housebuilding Act 2015.
- Urgent Crown development granted under s293A TCPA 1990.
- Development of a biodiversity gain site – development which is undertaken solely or mainly for the purpose of fulfilling, in whole or in part, the biodiversity gain planning condition which applies in relation to another development.
- Development related to the high speed railway transport network – development forming part of, or ancillary to, the high speed railway transport network comprising connections between all or any of the places or parts of the transport network specified in section 1(2) of the High Speed Rail (Preparation) Act 2013
2. How the process will work
The Environment Act amends the Town and Country Planning Act to make all planning permissions (other than exempted ones) subject to a pre-commencement condition requiring the submission of a plan that demonstrates how 10% net gain will be achieved. The management of the habitat created to achieve this must then be secured by legal agreement for a minimum period of 30 years.
The habitat creation required to achieve 10% net gain can be undertaken on the development site itself if space and circumstances allow, on a separate site or a mixture of the two. Offsite habitat creation can be undertaken on land owned by the developer, or on third party land where the landowner is willing to undertake such work and maintain it for at least 30 years in return for a payment from the developer. It is anticipated that a market will develop in the provision of such sites. As a last resort the Government intends to introduce a national credits purchase system for developments unable to meet their BNG requirements locally.
The National Park Authority has been reviewing options for offsite BNG units within and near to the National Park with landowners. Further information will be provided on this as options become available.
3. Information to be submitted with a planning application
The BNG process is built around a pre-commencement condition, which is when the full details of the metric calculations and of the measures to be taken to secure 10% net gain are required. However, enough information will be required at determination stage for the LPA to be satisfied that a suitable net gain solution exists for that development.
We await further guidance from Government about this, but it is likely to be most straightforward to submit all required information with the planning application whenever possible, so that discharge of the BNG condition can follow on immediately after determination. The metric calculations and associated reporting as well as the development of habitat creation to achieve net gain will need to be undertaken by an experienced Ecologist.
