Biodiversity Net Gain Metrics


Biodiversity Net Gain Metrics


The DEFRA Biodiversity Metric 2.0 tool, first published in July 2019, provides a way of measuring the total number of biodiversity units pre and post construction of a development. The tool produces a quantifiable number of biodiversity units to determine if there will be a net gain or a net loss in biodiversity after construction.

The Biodiversity Metric 2.0 uses habitat types to represent biodiversity values. The value of each habitat is then adjusted depending on its condition and location. Risk multipliers are applied to any habitat created or enhanced post construction. Separate calculations for linear habitats such as hedgerows and rivers can also be applied.

The Environment Bill published earlier this year confirmed the Government would mandate net gains in biodiversity for new planning applications in England and Wales. This will be brought into legislation within the year and will be mandatory for all developers to prove there will be a 10% biodiversity net gain post construction. The development will not be approved unless a Biodiversity Gain Plan has been submitted to the Local Planning Authority.

Prior to the tool being used, a Phase 1 Habitat Survey will be required to map and classify the current habitats onsite. Our experienced ecologists can provide advice during the design process to ensure that post construction, a biodiversity net gain of at least 10% will be met. Our ecologists can then use the tool to calculate the total net gain in biodiversity units which will be used to produce a Biodiversity Gain Plan to be submitted alongside the planning application. Our ecologists can also use the tool for any offsite biodiversity gains that may be required.