Partner Karen Jones, in our Planning & Environmental Law team, explains the mandatory requirements that developers need to be aware of in relation to biodiversity net gain.
The Environment Act 2021 introduces the mandatory “biodiversity net gain” (BNG) requirement for new housing and commercial development in England, subject to any exemptions that may apply. From November, the developers will need to provide a minimum of 10% biodiversity net gain for any new development in England that results in loss or degradation of habitat and for smaller sites the BNG requirement will apply from April 2024.
What is Biodiversity Net Gain?
The government guidance published on 21 February 2023 titled ‘Understanding biodiversity net gain’ states that “BNG is a way to contribute to the recovery of nature while developing land to ensure that the habitat for wildlife is in a better state than it was before development”. To minimise the impact on biodiversity, developers will need to provide minimum requirement of 10% of BNG.
A developer intending to develop land, must try to avoid loss of habitat of the land and if the developer is unable to do this, they have to create habitat either on site or off site. Provisions for offsite BNG will be either be on land away from the development site or buying units from a land manager. The government guidance states that if the developer cannot provide BNG either on site or on off-site land, then they must buy statutory credits from the government.
BNG will apply to development that requires:
- Planning permission granted under the Town and Country Planning Act 1990 (as amended) (the 1990 Act), where the development must provide of at least 10% of BNG.
- Development consent as a NISP granted under the Planning Act 2008. The BNG will need to be set out in biodiversity gain statement or where the relevant national policy statement contains such a statement.
BNG will apply to developers, land managers and local planning authorities.
Biodiversity Net Gain – Planning Condition
The requirement to provide mandatory BNG will apply to all new development under the town and country planning regime that results in loss or degradation of habitat. Schedule 7A of the 1990 Act (inserted by Environment Act 2021) sets out the details of new general condition and requires a biodiversity gain plan to be submitted and approved by LPA before development can lawfully commence. The biodiversity gain plan needs to contain an assessment of the value of natural habitats before development and after the development and ensure that at least 10% of net gain is achieved.
The 1990 Act allows for planning permission to be granted subject to a planning condition and is a deemed planning condition as it exists in statue. The planning condition can be met at the grant of planning permission, where a biodiversity plan has been approved by the local planning authority.
On 2 May 2023, Defra published guidance for England titled ‘What you can count towards a development's biodiversity net gain’. This is guidance for developers on how they can use habitat creation or enhancement towards their BNG. The Defra guidance states that if a developer is creating or enhancing habitat as part of its development, this may count towards its BNG and this will apply even if the habitat required for the development is to:
- Comply with a statutory obligation or policy, for example green infrastructure, environmental impact assessment (EIA) compensation or sustainable drainage.
- Provide river basin management plan (RBMP) mitigation and enhancement measures.
- Provide mitigation or compensation for protected species or sites, for example, nutrient mitigation.
Off-site mitigation and compensation for protected sites and species may also count towards BNG, however at least 10% of BNG should be done through other activities, for example, on-site habitat creation and enhancement. If the developer is using off-site units, this must be legally secured for at least 30 years, and registered, before they can count towards BNG. Habitat creation or enhancements do not count towards BNG if required for restocking conditions relating to a tree-felling licence, marine licensing, or remediation under the environmental damage regime.
Defra has yet to publish the draft regulations and it has also indicated that it will publish more guidance on final biodiversity gain template, appropriate use of off-site gains, what local planning authorities should take into consideration when creating legal agreements to secure biodiversity credits and statutory biodiversity credits.
Biodiversity metric and how it is calculated
Biodiversity metric is a habitat-based approach used to assess an area’s value to wildlife and uses habitat features to calculate a biodiversity value.
The biodiversity metric can be used by:
- ecologists or developers carrying out a biodiversity assessment
- developers who have commissioned a biodiversity assessment
- planning authorities who are interpreting metric outputs in a planning application
- communities who want to understand the impacts of a local development
- landowners or land managers who want to provide biodiversity units from their sites to others
On 24 March 2023, Natural England published version 4.0 of the proposed statutory biodiversity metric for measuring mandatory BNG for new developments in England under the 1990 Act and the Planning Act 2008. It also published an updated version of the small sites metric, which is a simplified version of the metric for use on small development sites. The full biodiversity metric and the small sites metric are accompanied by guidance and calculation tools. The metric scores different habitat types based on their relative value to wildlife, to calculate how a development will change the biodiversity value of a site.
The biodiversity value of any habitat or habitat enhancement are calculated in biodiversity units using the biodiversity metric. The metric uses habitats as a proxy for biodiversity value, however it does not address impacts on species, recognise the significance of site designations, or take account of indirect impacts, cumulative impacts or in-combination impacts.
The biodiversity value for the development is the total of the post-development biodiversity value of the on-site habitat, the biodiversity value of any registered offsite biodiversity gain allocated to the development and biodiversity value of any biodiversity credits purchased for the development.
Significant increases in onsite biodiversity value can only be considered by the local planning authority as part of the post-development biodiversity value if they are secured through a suitable mechanism and are maintained for at least 30 years after the completion of development. The local planning authority must be satisfied that any such habitat enhancement will be maintained for at least 30 years after the development is completed either by way of:
- A condition subject to which the planning permission is granted
- A planning obligation
- A conservation covenant (which is a new statutory scheme under the Environment Act 2021 for private voluntary conservation covenants).
The developer must commission a ‘competent person’ to conduct the habitat survey and assessment and use the approved metric. A ‘competent person’ is defined as being able to confidently identify the positive and negative indicator species for the range of habitats likely to occur in a given geographic location at the time of year the survey is undertaken. For a full metric application, the competent person should be an ecologist.
The biodiversity gain site register records biodiversity enhancement for registered off-site biodiversity gains as defined in paragraph 10 of Schedule 7A of the 1990 Act. The purpose of the register is to record allocations of off-site biodiversity gains to developments and make this information publicly available. Regulations will set out who establishes the register i.e. Natural England, which land is eligible to be registered, procedures and fees.
Exemptions to Biodiversity Net Gain requirement
The exemptions that apply to the BNG requirements are:
- habitats below a ‘de minimis’ threshold of 25 metres squared; or
- five metres for linear habitats like hedgerows
- householder applications
- biodiversity gain sites
- and small-scale self-build and custom housebuilding.
For the latter exemption, Defra state that they will be aiming “to define this exemption in a way that addresses the risks of exempting large sites made up of many custom plots and will keep this under review.”
Comment
Developers need to consider BNG from the outset for any proposals. Planning applications should be supported by a biodiversity gain plan complete with the Biodiversity Metric calculations. The biodiversity plan should outline how net gain in biodiversity will be achieved and managed for a minimum of 30 years after development and how this will be secure whether via planning condition or a planning obligation.
For phased development, developer will require a biodiversity gain plan for each phase of the project, subject to approval prior to commencement.
For further information or legal advice, please contact law@blandy.co.uk or call 0118 951 6800.
This article is intended for the use of clients and other interested parties. The information contained in it is believed to be correct at the date of publication, but it is necessarily of a brief and general nature and should not be relied upon as a substitute for specific professional advice.
