From January 2024, developers will be required to deliver at least a 10% net gain in biodiversity as part of all large schemes in England, with the requirement also being implemented for small schemes from April 2024. Our planning director Dan Hughes looks at the new BNG requirements in more detail and answers some frequently asked questions.
The new rules on biodiversity net gain have been a long time coming, so shouldn’t come as a major surprise for most property developers and land managers.
First introduced under the Environment Act 2021, the implementation of the 10% net gain mandate was originally delayed by the Covid-19 pandemic.
It had then been due to become a legal requirement in November 2023. However, the government announced in September 2023 that the legislation wouldn’t be implemented until January 2024 to give local planning authorities, developers, and landowners further time to prepare.
What is Biodiversity Net Gain and how can developers deliver on it?
Put simply, biodiversity net gain is an approach to development or land management that aims to leave the natural environment in a measurably better state than it was in prior to development.
Shorthand for ‘biological diversity’, biodiversity refers not just to animals but the variety of all living organisms including insects, plants, bacteria and fungi.
Therefore, the BNG rules exist to deliver measurable improvements for biodiversity by enhancing existing habitats or creating new ones.
When does Biodiversity Net Gain become mandatory?
Developers will need to achieve at least 10% biodiversity net gain for all large residential, commercial, and mixed-use schemes starting in January 2024, unless the site is exempt.
Biodiversity net gain for small sites will become mandatory from April 2024, while implementation of the BNG rules for Nationally Significant Infrastructure Projects is expected to come in in 2025. The legislation will not apply to marine-based projects.
What does the BNG legislation entail and who enforces it?
The legislation is made under the Environment Act which amends the Town and Country Planning Act. In essence, this makes the minimum 10% net gain in biodiversity a condition of planning permission.
The minimum 10% gain in biodiversity will be calculated using the Biodiversity Metric, a habitat-based approach to determining a biodiversity value that’s been developed by Natural England. Those seeking planning permission for development will have to submit a biodiversity gain plan as part of their application.
Habitats created under the plan will be secured for at least 30 years by way of planning obligations or conservation covenants. The gains must be delivered either on-site, off-site, or via a new statutory biodiversity credits scheme and a national register for net gain delivery sites.
The biodiversity credits scheme allows the UK government to sell biodiversity credits to developers if the required biodiversity net gains cannot be achieved on-site or through the off-site market.
What constitutes a small site under the biodiversity net gain rules?
For residential development, a small site for the purposes of BNG is one with up to nine homes on less than one hectare of land. Where the number of dwellings is not known, the site must have an area less than 0.5 hectares.
For non-residential development, a small site is one where the floor space to be created is less than 1,000 square metres or where the site area is less than one hectare.
Who can advise developers and landowners on biodiversity net gain?
Local planning authorities, professional planning consultants, ecology teams, and other professional advisors will all play a role in supporting private developers, landowners and farmers to adjust and comply with the new rules on biodiversity net gain.
Developers will need to factor in BNG planning for the developments, seeking advice from their professional teams at the earliest opportunity.
