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Biodiversity Net Gain – requirements for developers have now become law

From 12th February 2024 mandatory biodiversity net gain (BNG) requirements, part of the Environment Act 2021, became effective. This means that developers must ensure a minimum 10% net gain in biodiversity based on a pre-development assessment of the land they are developing, to secure planning permission. Some councils will demand higher percentages, such as 20%.

For major development applications in England, (which broadly means residential projects of 10 or more houses or commercial buildings with over 1,000 square meters of floor space) mandatory BNG applies from 12 Feb 2024. From April 2024, small-site developments must comply, while Nationally Significant Infrastructure Projects will follow suit in 2025, although they are currently exempt pending confirmation on the application.

Exemptions cover developments with minimal impact on habitats, householder applications, approval of reserved matters, biodiversity gain sites, and irreplaceable habitats (if separately compensated). A Biodiversity Gain Plan detailing the gain strategy is mandatory, to be approved by the planning authority before development commencement, typically within 8 weeks, unless agreed otherwise.

If a developer is unable to achieve the required level of BNG within the development site (on-site BNG), they can purchase BNG credits/units from landowners who can deliver BNG through schemes on their land (off-site BNG).

The statutory biodiversity metric assesses pre and post-development habitat values, including offsite gains or credits. Habitat management, either onsite or offsite, must be maintained for 30 years, secured through conditions, planning obligations, or conservation covenants. Section 106 agreements ensure enforceable commitments, while conservation covenants, less restrictive, involve private agreements with responsible bodies like councils or charities.

This new legislation will unlock opportunities for landowners to create biodiversity improvement schemes and sell units to developers. Our planning team have already worked on a several credit selling agreements and advise landowners and developers on the legal framework required for these contracts. Over the coming months we expect to see the demand for credits increase as developers seek to unlock planning permissions. If you are considering selling biodiversity credits it is important to fully understand the implications of the contracts as they have both short and long terms impacts on your farming business. Our team can help both draft and check agreements giving you piece of mind whilst enabling you to benefit from this significant new legislation.

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For further information please get in touch with our expert planning team.


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