All new developments will have to improve biodiversity on their site by a minimum of 10% under the new Environment Act in a bid to boost sustainability.
Biodiversity Net Gain (BNG) is an approach used to improve a site’s biodiversity value – habitat creation or enhancement after proving they have avoided or mitigated harm.
The Environment Act mandates developers to deliver a mandatory 10% biodiversity net gain to be maintained for a period of at least 30 years. Development proposals must “leave biodiversity in a better state than before”.
They must determine and evidence a project’s final BNG value using the specified Defra biodiversity metric if they want their plans to move through the planning process swiftly.
To achieve biodiversity net gain, proposals must follow the ‘mitigation hierarchy’ which states planning applicants must first avoid harm, then mitigate or finally compensate for losses on-site, off-site or through a combination of the two solutions. These measures will be required in all planning conditions from next year.
Trish Holden, Director of Ecology Services, said current guidelines are outlined in the National Plan Policy Framework (2021), in particular paragraph 174 (d), ‘minimising impacts on and providing net gains for biodiversity. 179 (b), ‘promote the conservation, restoration and enhancement of priority habitats, ecological networks and the protection and recovery of priority species; and identify and pursue opportunities for securing measurable net gains for biodiversity’
and 180 (d) development whose primary objective is to conserve or enhance biodiversity should be supported; while opportunities to improve biodiversity in and around developments should be integrated as part of their design, especially where this can secure measurable net gains for biodiversity or enhance public access to nature where this is appropriate’.
We also have British Standard on biodiversity net gain and development projects: BS 8683:2021 Process for designing and implementing Biodiversity Net Gain.
Trish added: ‘Upcoming is the Environmental Act which will transpose down to Local Level – so local plans will need to be updated to reflect net gain (and set a target most will be 10%). The EA polices for net gain won’t come into force until winter 2023. However, London Plan already are on the ball and have this 10% net gain mentioned in Policy G6.’
But what they expect the EA to deliver is the following:
- Minimum 10% gain required calculated using Biodiversity Metric
- Habitat secured for at least 30 years via obligations/ conservation covenant
- Habitat can be delivered on-site, off-site or via statutory biodiversity credits
- There will be a national register for net gain delivery sites
- Will also apply to Nationally Significant Infrastructure Projects (NSIPs)