BIODIVERSITY NET GAIN
What are BNG Credits?
Biodiversity Net Gain (BNG) is a strategy for development and land management that focuses on enhancing the natural environment, ensuring it is left in a better and measurable state than before.
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The term ‘biodiversity’ is derived from ‘biological diversity,’ which encompasses the wide range of all living organisms, animals, insects, plants, bacteria, and fungi.
Biodiversity net gain drives measurable improvements for biodiversity by creating or enhancing habitats alongside development. These improvements are quantified using the Biodiversity Metric, which calculates a proxy value in Biodiversity Units to represent a site’s ecological value.
As mandated by the Environment Act 2021, all planning permissions granted in England (with a few exceptions) must deliver a minimum of 10% biodiversity net gain, except for small sites.
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Biodiversity net gain can be achieved through on-site, off-site, or a combination of both on-site and off-site measures.
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There are two types of offsetting: private market credits and statutory credits.
Private Market Credits
Private market credits are provided by landowners. Projects that deliver measurable biodiversity improvements can be quantified using specific metrics and offered to the market. This forms the basis for most off-site biodiversity credit sales. Off-site projects must be secured through a Section 106 legal agreement, a standard planning tool, or a Conservation Covenant with a responsible body. When secured, off-site credits must be registered on the national register to ensure transparency and maintain a public record.
Statutory Credits
Statutory biodiversity credits are government-held credits available to developers who cannot find suitable offsets for their projects. These credits are typically used for small sites without strategic offset solutions or for projects impacting rare habitats that are otherwise unavailable in the country.
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Under the statutory biodiversity net gain framework, most planning permissions are subject to the biodiversity gain condition, requiring at least a 10% increase in biodiversity value compared to the site's pre-development state. This gain can be achieved through:
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Onsite biodiversity improvements
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Registered offsite biodiversity gains
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Statutory biodiversity credits
Biodiversity net gain is addressed post-permission to ensure compliance. Once planning permission is granted (unless exempt), a Biodiversity Gain Plan must be submitted and approved before development begins. This plan ensures the biodiversity gain condition is met by:
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Using the statutory biodiversity metric to calculate biodiversity value pre- and post-development
Measuring habitat characteristics like type, size, distinctiveness, condition, and location
Demonstrating correct application of the metric through submitted calculation tools.
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This framework ensures a structured and measurable approach to enhancing biodiversity in new developments.
