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Biodiversity Net Gain London: How we can assist

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Biodiversity Net Gain London

Biodiversity net gain (BNG) is an approach to development that is already well-known in legislation across the UKs local planning authorities. However, BNG is set to become a mandatory part of all development and planning applications by January 2024 through the Environment Act 2021.

Biodiversity Net Gain refers to the process in which a project or development site has to consider its impact on the surrounding irreplaceable habitats and environment. This means that developers must adapt their planning processes, both for major applications and minor developments, to ensure no damage is done to any local ecosystems. Developers must aim to conserve and enhance biodiversity in the area of a development project.

A biodiversity net gain plan ultimately aims to leave the natural environment around a development in a measurably better state than 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 have planning permission granted in England. This is with the aim that developers will demonstrate how the development proposal will benefit the environment around them.

BNG requirements essentially act 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 Act 2021, local authorities must require all developers to achieve at least 10% biodiversity from 2024 onwards. The Environment Act has implemented a strengthened legal duty for developers and local authorities to consider BNG.

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 biodiversity 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 ecological features through habitat creation and retention, 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 kilometres 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.

Biodiversity Units

Biodiversity net gain involves quantifying the change in biodiversity value resulting from development projects. Biodiversity net gain units refer to the standardised measurements used to assess biodiversity, such as the number of species, habitat area, ecological functionality, etc. These biodiversity net gain units can then be used to assess whether any mitigation measures may need to be used to meet planning obligations.

To calculate the uplift, the number of units is increased by a minimum of 10%. This value is the number that will be required to be delivered in order to obtain development planning permission.

Biodiversity net gain can be implemented on-site and should be maintained for a minimum of 30 years. If net gain of 10% or more cannot be completed and maintained on-site, or can only be partially completed on-site, the remainder can also be accommodated off site using biodiversity banking.

BNG planning

To secure planning approval for a development from a Greater London authority, it is imperative to demonstrate your commitment to enhancing biodiversity net gain. A crucial initial step involves engaging a proficient ecologist to craft and refine a biodiversity net gain plan.

Based on the ecologist’s discoveries in a BNG assessment, the proposal will assist in identifying natural elements that might face potential risks due to the development project, as well as suggesting mitigation strategies to avert such impacts.

How can we assist with achieving biodiversity net gain, London?

Our London ecology unit has helped numerous clients over the years, including issuing policy guidance for biodiversity gain in the London area. Achieving biodiversity net gain, London, through development is something that we are qualified and experienced in.

Our team of ecologists are experts in the field of biodiversity net gain and can keep you up to date with local plans 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 to meet biodiversity reporting requirements. 

Please get in touch if you would like further information about Biodiversity Net Gain, London, or BNG 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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