Biodiversity Net Gain (BNG) means that developers must make sure that the habitat for wildlife on land they plan to do development work on has more biodiversity after development than it was before development by protecting the habitat and creating new habitat either on-site or off-site.
Developers will have to assess the amount and condition of the habitat on their development site and show they will deliver a net gain of 10% in biodiversity, with the preference being for on site provision. If necessary provision can be off-site. If on-site or off-site land cannot be used, as a last resort developers must buy statutory credits from the government. They must provide strong evidence justifying this option.
These requirements will apply from November 2023 for developments requiring planning permission, unless exempt. It will apply to small sites from April 2024.
In Cornwall the adopted Climate Emergency Development Plan Document includes Policy G2 which covers Biodiversity Net Gain. This policy need not be repeated in Cornish NDPs, but should be reflected in other policies.