Government updates planning rules to secure biodiversity improvements

The Government has announced changes to the planning system which will require developers to improve their environmental performance and follows greater public awareness of the impact of climate change.

The latest changes to the National Planning Policy Framework (NPPF) will make it mandatory for developers to improve the biodiversity of their sites by 10 per cent for their projects. The move coincides with the combined efforts of David Attenborough, interest in tackling plastics waste and rise of Extinction Revolution.

Tim Spicer, Associate Director at DHA, which has offices in Maidstone and Crawley, said: “The Government has stipulated that measurable biodiversity net gain will be a mandatory requirement for all major planning applications. This will require developers to assess the biodiversity of their sites at the time of the application and then demonstrate that it will deliver a measurable 10 per cent net improvement when the development is completed.

“As with any amendment to policy, it often takes a period for the precise implications of the changes to be fully understood and how the rather ambiguous wording within the NPPF is to play out in practice.”

The team at DHA is increasingly being asked to provide evidence to demonstrate measurable net gains using the Defra Biodiversity Metric, with the latest version available on Natural England’s website. This is set to become widespread following the introduction of the mandatory 10% net gain to be introduced by Defra as part of planning policy.

Tim Spicer added: “A number of our clients have already been investigating options for providing greater bio-diversity mitigation for developments as part of their social and environmental responsibilities. These new measures will seek to confirm what a number of responsible developers are already doing.”

The metric calculates the value of a habitat type present within a site in terms of ‘biodiversity units’ by attributing it a numerical value (0-8) multiplied by the area it occupies. It then calculates the relative loss of a habitat in comparison to the proposed replacement habitat types being created or restored and managed, which is presented as a numerical value e.g. a net gain of numerical biodiversity units or a net loss.

Tim Spicer added: “With any system that tries to simplify a complex real-world situation the metric is not without its flaws, but irrespective of its shortfalls, the approach demanded by the metric often requires larger areas of habitat creation than would typically be expected in order to demonstrate net gain.

“We believe it is prudent to engage an ecologist who is familiar with the metric to define areas needed to achieve net gain early in the project design. This will help prevent delays later in the project and the implications of having to retrofit a scheme later in the process or even after submission.

“Whilst off-site biodiversity offsetting remains an option in theory, the mechanism through which to secure this either doesn’t exist or is more convoluted.”

DHA recommends the use of the metric to its clients at the earliest possible stage of the design process.

For more information call 01622 776226 or email:

Share this