Biodiversity Net Gain: Local Planning Authority duties and key roles for developers | Fieldfisher
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Biodiversity Net Gain: Local Planning Authority duties and key roles for developers


United Kingdom

This briefing is focused on what Local Planning Authorities (LPAs) can do to prepare for the introduction of mandatory Biodiversity Net Gain (BNG), and how developers can support them as part of the planning application process.


Under the Environment Act 2021 (EA 2021), nearly all planning permissions granted in England (with a few exemptions) will have to deliver at least 10% BNG from January 2024 (and from April 2024 for small sites).

Mandatory BNG for nationally significant infrastructure projects is still planned for 2025.

The Government is spending over £15 million to assist LPAs to prepare for the introduction of BNG. By the end of November 2023, the Government has committed to publishing regulations and guidance on:

  • "the statutory biodiversity metric, critical for calculating the correct biodiversity gain
  • the draft biodiversity gain plan template, which will help developers prepare for what they will need to complete during the planning application stages
  • the Habitat Management and Monitoring Plan template, which will set out how the improved significant on-site and off-site habitats will be managed for the long term
  • a package of Biodiversity Net Gain guidance that sets out further advice for landowners, developers, and Local Planning Authorities around their role and responsibilities in delivering mandatory Biodiversity Net Gain"

Benefits of mandatory BNG to an area

BNG is a strategy to develop land and contribute to the recovery of nature ensuring the wildlife habitat is in a better state than it was before development.

It will create new/enhanced greenspaces, bringing nature to local areas. Greener neighbourhoods are more attractive to both current and future occupiers, which could lead to increases in property prices.

BNG can also finance new/existing green infrastructure, contributing towards the Government's Net Zero targets. It will enable the UK as a whole and individual communities to better adapt to climate change through the restoration and protection of nature (e.g. additional woodland will assist in reducing carbon dioxide).

For the economy, mandatory BNG can also be beneficial, creating long-term income opportunities for landowners through investment in habitat management.

What should LPAs do now?

The Local Government Association states: "Our experience of working alongside local authorities has led us to believe that [BNG], and getting to the point where net gain can be delivered, is a journey for local authorities."

We understand from our discussions with LPAs, that while they are in the midst of preparing for mandatory BNG, most have welcomed the delay in its introduction.

The introduction of mandatory BNG has been regarded as an administrative burden with the additional/enhanced duties to comply with, and the documents to be produced/amended.

However, it is recognised that when BNG 'processes' have been fully established and embedded into the planning application process, there will be benefits for LPAs (especially when acting as a land manager).

Below are some key actions LPAs should take now in preparation for January 2024 (and suggestions for how developers can help).

1. Ensure everyone in the LPA knows about BNG (and the biodiversity metric) – It is essential for everyone to understand the legislative basis to the obligation, the current biodiversity metric and related guidance in advance of the statutory biodiversity metric being published later this month.

The metric is used to assess an area's value to wildlife. It can be used by LPAs who need to interpret metric outputs in planning applications and developers carrying out or commissioning a biodiversity assessment, along with ecologists carrying out assessments, and landowners/land managers who are wanting to provide biodiversity units to other sites.

When carrying out/commissioning biodiversity assessments, developers should ensure the information is as clear as possible to aid the LPA's consideration of BNG and the application – this could also mean planning applications are decided more swiftly.

2. Local partnerships – LPAs and developers should engage with environmental charities, local environmental records centres, local nature partnership, and statutory agencies (i.e. Natural England) and other organisations who have a role in delivering mandatory BNG to agree plans and protocols for its delivery.

3. Local plans, strategies, and policies – LPAs should consider how to include BNG requirements in their local plans.

Supplementary planning documents could be created to provide guidance and details for developers and landowners on how to comply with BNG. LPAs should also be updating/creating information and policies on enhancement priorities and local habitat creation.

All of these documents, policies, guidance and information should be on the LPA's website.

LPAs should also review the following strategies to see how they will comply with their biodiversity duty:

a. local nature recovery strategies for environmental improvement which will contain a local habitat map and statement of biodiversity priorities;

b. species conservation strategies to protect the future of at risk species; and

c. protected site strategies to provide way to overcome offsite pressures (i.e. pollution of nutrients).

BNG should also influence how LPAs plan for and deliver other policies, such as those relating to nutrient neutrality, water neutrality and flood risk. 

4. Enforcing bodies for on and off-site gains – BNG will need to be legally secured for 30 years by way of a planning obligation, conditions and or conservation covenants. This will be dealt with in more detail in one of our forthcoming briefings. LPAs should consider (if they have not already) whether to be an enforcing body and how they will work with land managers and charities.

5. Phased development – Developers will need to provide LPAs with additional information setting out how BNG will be achieved throughout the whole development and how this could be delivered in phases. Such additional information will be expected to form part of the planning application – the information required will be set out in secondary legislation.

Preference will be that BNG works will be expected/required for each phase, and there will be no front-loading requirement for BNG works to be undertaken in the early phases. It is important to note that LPAs will have some discretion on this respect and certain schemes will require BNG delivery programmes with more robust timetables.

6. Biodiversity duty and report – Section 102 of the EA 2021 introduces the following duties on LPAs. They must:

a. consider how to conserve and enhance biodiversity;

b. agree policies and objectives based on such consideration; and

c. act to deliver such policies / achieve such objectives.

If there is already a strategy in place that monitors environmental performance, the BNG actions can form part of that strategy. However, LPAs should definitely consider creating a new standalone document if this is not the case.

Section 103 of the EA 2021 introduces the requirement for LPAs to publish biodiversity reports. The reports will document the actions the LPA has undertaken to comply with its biodiversity duty. This must be published no later than 1 January 2026 and within every five-year period thereafter. Examples of report structure are available online.

The Government has also commenced the parts of the Environment Act 2021 that allow the statutory BNG metric to be provided and the biodiversity gain register to be established.

We work with LPAs and developers on all legal aspects of the LPA requirements and obligations. If you have any questions about what BNG may mean for you, please do not hesitate to contact the Planning and Environment Team at Fieldfisher.

Areas of Expertise

Real Estate