Collington Winter Environmental

Biodiversity Net Gain Norfolk: How we can assist

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Biodiversity net gain (BNG) is already well-known in legislation across the UKs local planning authorities. However, BNG it is set to become a mandatory part of all development and planning applications at the end of 2023.

BNG refers to the process in which a project or development site has to consider its impact on the surrounding irreplaceable habitats and environment. This mean that developers must adapt their planning processes, both for major applications and minor developments, to ensure no damage is done to any local ecosystems.

A biodiversity net gain plan ultimately aims to leave the natural environment around a development in a better condition that it was prior to the development. This could be achieved through enhancing local habitats surrounding and within the development.

Local planning authorities are frequently asking developers to meet the requirements for BNG in order to obtain planning permission. This is in hope the developers will demonstrate how the project will benefit the environment around them. BNG essentially acts as a planning condition as well as a policy requirement for planning consent. As such, complying with biodiversity net gain is a significant factor in whether planning permission is granted or denied.


Is biodiversity net gain mandatory?

Following the Environment Bill 2021, local authorities must require all permissions they grant to achieve at least 10% biodiversity. A provision for secondary legislation has been put into place from the act, which will set a date in which the mandate will come into force. The mandate is predicted to come into force in late 2023. The 2021 act gives a two-year transition period for authorities to get their policies and processes in place before it becomes mandatory.

As well as detailing the developments impact on biodiversity, developers must also use mitigation techniques using the mitigation hierarchy if the development does not meet required standards. This includes offsetting BNG and maintaining it for at least 30 years.

Calculating biodiverity net gain

Comparisons can be made between the existing value of a site and what will be delivered through development or management and post development. This may include an increase in natural habitats and ecological features through retention and enhancement and/or creation, which goes over and above the environmental habitat originally on site.

Biodiversity net gain increase can be calculated through the DEFRA biodiversity metric 4.0, which requires a limited number of factors. These factors include:

 The type of habitat (both on and off site)

  • Any locations (if they are local environment priorities)
  • The size of habitat parcels in kilometers or hectares
  • The condition of any habitat parcels

The government website also provides a biodiversity metric 4.0 calculation tool. This can help to determine your BNG unit score that translates into the standards of the local authority.

How can we assist with achieving BNG?

Our Norfolk ecology unit has helped numerous clients over the years, including issuing policy guidance for biodiversity gain in the Norfolk Council area. Achieving net gain for biodiversity through development is something that we are qualified and experienced in. Plus, we can offer advice on planning projects.

At Collington Winter, our team of ecologists are experts in the field of biodiversity net gain and can keep you up to date with new and changing legislation. As regulations can vary across local authorities it is important to instruct a qualified ecologist to ensure you are following the correct rules. 

Please get in touch if you would like further information about Biodiversity Net Gain, Norfolk, or biodiversity net gain plans. We are happy to offer free CPD sessions on the Biodiversity Net Gain Principles and how we can help your schemes achieve this.


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