Biodiversity Net Gain in England ; An Introduction (Part 1)
Biodiversity Net Gain (BNG) is a principle which aims to leave the natural environment in a better state after development than that in which it stood before development takes place. Mandatory statutory requirements for a development to provide net gain apply to planning permissions granted on or after 12 February 2024 (unless an exemption applies).
In addition to the mandatory statutory requirements, Biodiversity gain is encouraged by policy in the National Planning Policy Framework (NPPF), and may be a requirement of local planning policy. Some Local Planning Authorities (LPAs) may have included BNG policies in their local plan, and it is vital for prospective developers to check whether this is the case before submitting a planning application, because both statutory and policy-based BNG may apply.
The BNG Planning Practice Guidance (PPG) was finalised on 14 February 2024. It applies to statutory-based (rather than policy-based) BNG.
Background to mandatory Biodiversity Net Gain:
The 25-year Environment Plan, published in January 2018, sets out a commitment by the Government to strengthen the requirements in the NPPF on BNG. It contained confirmation that the Government would consult on whether a mandatory requirement should be introduced for development in England to deliver BNG, to ensure that necessary development can proceed while improving the environment by more than compensating for biodiversity loss where it could not be avoided or mitigated.
The Environment Act 2021 (EA 2021) received Royal Assent on 9 November 2021. It inserts provisions into the Town & Country Planning Act 1990 (TCPA 1990) to make planning permissions automatically subject to a requirement to deliver 10% BNG, from 12 February 2024. The Biodiversity Gain planning condition does not apply in relation to:
• a planning permission where the application was made before 12 February 2024
• planning permission granted further to an application made under TCPA 1990, section 73 where: (a) the original planning permission to which the TCPA 1990, section 73 planning permission relates was granted before 12 February 2024; or (b) the application for the original planning permission to which the TCPA 1990, section 73 planning permission relates was made before 12 February 2024
On 19 January 2023, several Statutory Instruments were made, putting in place the BNG legislative framework, which came into force on 12 February 2024 in line with the BNG launch date. A statutory version of a biodiversity metric tool was also made available from 29 November 2023.
Biodiversity Net Gain Objective
TCPA 1990 provides that all grants of planning permission in England are subject to a condition to secure that the “BNG Objective” is met.
It also states that the BNG Objective is to be treated as having been met in relation to a development for which planning permission is granted if the biodiversity value attributable to the development exceeds the pre-development biodiversity value of the “Onsite Habitat” by at least 10%.
‘Onsite Habitat’ is defined as ‘the habitat on the land to which the planning permission relates’. It is important to distinguish ‘habitat’ from, for example, ‘species’, which will not be a factor in calculating the biodiversity value.
For these purposes, the biodiversity value attributable to the development is the total of:
• the post-development biodiversity value of the Onsite Habitat
• the biodiversity value of the development of any registered Offsite Biodiversity Gain allocated to the development, and
• the biodiversity value of any biodiversity credits purchased for the development.
The biodiversity value is calculated by ecologists who will work closely with the developer in the planning application process.
The 10% BNG must be maintained for at least 30 years after the completion of habitat enhancement works.
The habitat creation, enhancement and management work should start as soon as possible, or within 12 months of the development commencing at the latest.
Planning Application
An application for planning permission in England must be accompanied by information relating to the Biodiversity Gain condition, such as whether the applicant believes that planning permission, if granted, would be subject to the Biodiversity Gain condition and, if not, the reason for that belief.
In recognition that phased development can often be implemented over a long period of time, TCPA 1990 distinguishes between the overall Biodiversity Gain plan (the ‘overall plan’) on the one hand, and a phase Biodiversity Gain plan for each phase before development takes place (the ‘phase plan’) on the other.
The Act specifies that that every planning permission granted for the development of land in England is deemed to have been granted subject to the condition that development cannot start, unless:
• a Biodiversity Gain plan for the whole development has been submitted to the relevant planning authority and
•the planning authority has approved that plan.
(The general rule is that the relevant planning authority is the LPA which granted the planning permission, or the one which could have granted the planning permission had it not been granted by the Secretary of State).
The Act provides that, in the case of a phase plan, the first and each subsequent phase of development cannot start, unless:
• a biodiversity gain plan for that phase has been submitted to the relevant planning authority, and
• the planning authority has approved that plan.
Submission of Biodiversity Gain plan
A 2015 Statutory Instrument sets out the requirements about the form, timing and contents of the Biodiversity Gain plan.
The Department for Environment, Food & Rural Affairs (DEFRA) has published Biodiversity Gain plan templates (including for phased developments) and guidance on how to submit a Biodiversity Gain plan.
A habitat management and monitoring plan (HMMP) can provide the management and monitoring information for significant onsite enhancements and offsite gains. The HMMP gives a detailed schedule of what the applicant needs to do to create and enhance habitats for BNG and manage and monitor the habitat for at least 30 years. DEFRA has published guidance on creating a HMMP for BNG , which links to a template HMMP.
Submission of a Biodiversity Gain plan must be accompanied by payment of the relevant fee.
Biodiversity Gain plan: overall plan
TCPA 1990 defines a Biodiversity Gain plan as being—for the purposes of an overall plan—a plan relating to development granted by outline permission or any other kind of planning permission, where the grant is subject to conditions, which must specify:
• information about the steps taken, or to be taken, to minimise the adverse effect of the development on the biodiversity of the Onsite Habitat and any other habitat
• the pre-development biodiversity value of the Onsite Habitat . It is good practice to obtain good evidence of the existing habitat and condition of the site for the purposes of specifying the pre-development biodiversity value
• any registered Offsite Biodiversity Gain proposed to be allocated to the development and the biodiversity value of that gain in relation to the development
• any biodiversity credits proposed to be purchased for the development
• where the Biodiversity Gain plan does not relate to a development for which planning permission has been granted under TCPA 1990, section 73 for the development of land without complying with conditions subject to which a previous planning permission was granted (a ‘section 73 case’): the post-development biodiversity value of the Onsite Habitat of the development, as well as for each phase of development, and the strategy for meeting the Biodiversity Gain objective if, after the development has started, there is a change in the information provided
• in a section 73 case: the post-development biodiversity value of the Onsite Habitat for each phase of development, any registered Offsite Biodiversity Gain allocated to the development and the biodiversity value of that gain in relation to the development before the date of submission of the overall plan, any biodiversity credits purchased for the development before the date of submission of the overall plan, and the strategy for meeting the Biodiversity Gain objective if there is a change in the information provided, as well as the reasons for any departure from the strategy specified in the overall plan approved.
Biodiversity Gain plan: phase plan
TCPA 1990 defines a Biodiversity Gain plan as being—for the purposes of a phase plan—a plan relating to development granted by outline permission or any other kind of planning permission, where the grant is subject to conditions, which must specify:
• the post-development biodiversity value of the Onsite Habitat for the phase of the development to which the phase plan relates
• the post-development biodiversity value of the Onsite Habitat for each other phase of development (whether started or not)
• any registered offsite Biodiversity Gain allocated to the development and the Biodiversity value of that gain in relation to the development before the date of submission of the phase plan
• any registered offsite Biodiversity Gain which is proposed to be allocated to the development and the biodiversity value of that gain in relation to the development
• any biodiversity credits purchased for the development before the date of submission of the phase plan
• any biodiversity credits proposed to be purchased for the development
• the strategy for meeting the Biodiversity Gain objective if there is a change in the information provided, and the reasons for any departure from the strategy.
Approval of Biodiversity Gain plan
The LPA has to give written notice, to the person submitting the Biodiversity Gain Plan, of approval or otherwise of the plan within either eight weeks, beginning with the day after the day on which the LPA receives the plan, or such longer period as is agreed in writing between that person and the LPA.
Approval of overall plan
The LPA can only approve the Biodiversity Gain plan in relation to an overall plan if the authority is satisfied that:
• the pre-development biodiversity value of the Onsite Habitat is as specified in the plan
• where the Onsite Habitat of any part of a development is irreplaceable habitat, the adverse effect of the development on the biodiversity of the Onsite Habitat is minimised and appropriate arrangements are made to compensate for any impact
• in short, the Biodiversity Gain objective is met, taking into account relevant factors.
Approval of phase plan
The LPA can only approve the Biodiversity Gain plan in relation to a phase plan if the authority is satisfied that:
• the pre-development biodiversity value of the Onsite Habitat is as specified in the plan
• the post-development biodiversity value of the Onsite Habitat is at least the value specified in the plan
• the registered offsite Biodiversity Gain allocated to the development has the biodiversity value specified in the plan in relation to the development
• any biodiversity credits specified in the plan as purchased for the development have been so purchased, and
• the Biodiversity Net Gain objective is met.
Biodiversity gain hierarchy
In deciding whether to approve the plan, the LPA must take into account how the Biodiversity Gain “Hierarchy” (the Hierarchy) must be followed, and any reasons where it cannot be followed (except in relation to irreplaceable habitats where the Hierarchy does not apply).
The Hierarchy means the following actions in the following order of priority:
• avoiding adverse effects of the development to Onsite Habitat with a habitat distinctiveness score, applied in the biodiversity metric, equal to or higher than six
• so far as those adverse effects cannot be avoided, mitigating those effects
• so far as those adverse effects cannot be mitigated, habitat enhancement of Onsite Habitat
• so far as there cannot be that enhancement, creation of Onsite Habitat
• so far as there cannot be that creation, the availability of registered offsite Biodiversity Gain
• so far as that offsite habitat enhancement cannot be secured, purchasing biodiversity credits.
Appeal against LPA’s determination on biodiversity gain plan
The applicant has the right to appeal the non-determination or refusal of the Biodiversity Gain plan within six months of the date of determination, or the expiry of the time limit for determination where no determination is given. The government has published guidance on appealing a Biodiversity Gain plan and on how to complete an appeal form.
Exceptions:
The Net Gain provisions do not apply to:
• permitted development, and
• urgent Crown development
• any other development specified in Regulations.
Exemptions:
The Biodiversity Gain Requirements (Exemptions) Regulations 2024 exempt certain developments from meeting the BNG requirement. They relate to:
• “small developments” where an application for planning permission is made or has been granted before 2 April 2024.
• development impacting habitat of an area below a ‘de minimis’ threshold of 25 metres squared, or five metres for linear habitats such as hedgerows with no impact on priority habitat—i.e. a habitat specified in a list published under section 41 of the Natural Environment and Rural Communities Act 2006
householder applications
• the high-speed railway network
• offsite gain developments, i.e. developments which fulfil the BNG requirement arising in relation to another development, and
• certain self-build and custom build developments, where the development consists of no more than nine dwellings and is carried out on a site which has an area no larger than 0.5 hectares.
(This article is not intended to be comprehensive or to provide specific legal advice. It should not be relied upon in the absence of specific advice given in relation to particular circumstances.)
For further information, please contact: Natalie Linehan, Andrew Williamson or David Thorp