Maximising Biodiversity Net Gain for Developers

An ecological assessment will first need to be be conducted before any development begins to measure the baseline biodiversity value of the site. Using the project plans, another measurement will be taken to predict the expected biodiversity value after the development. By comparing these two readings, necessary changes can be made to ensure a 10% increase in biodiversity, removing any obstacles that may prevent the local planning authority from granting approval for the site.

Once the current biodiversity value is determined, the applicant will calculate the number of Biodiversity Units required to achieve their desired net gain in biodiversity after the development. These units can be created within the development site or in a suitable location elsewhere if necessary.

This information must be submitted as part of a new planning application and approved by the Local Authority before planning permission is granted. Our team of experts can help not only assess and plan your project but deliver and review it too, please get in touch with our consultancy team for a quote to do this work for you.

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Biodiversity net gain is underpinned by the mitigation hierarchy, which is set out in the National Planning Policy Framework. The Mitigation Hierarchy outlines a sequential approach to addressing impacts from development on biodiversity, prioritised as per below:

1. Avoidance: project proposals should firstly seek to avoid any adverse impacts on biodiversity through symapathetic scheme design.
2. Minimise: where avoidance is not feasible, adverse impacts on biodiversity should be minimised by modifying scheme design and strategy as much as possible.
3. Mitigate: all non-avoidable adverse impacts on biodiversity must be adequately replaced or mitigated for, on the development site.
4. Offset or Compensate: the final resort after all other options have been exhausted is to offset or compensate for the adverse impacts on biodiversity through offsite compensation.

Whilst biodiversity net gain relates only to habitats, the mitigation hierarchy is applied to all aspects of ecology and potential for avoidance, minimisation, mitigation and offsetting impacts on species will also need to be considered outside of a BNG approach.

It is crucial to adopt a ‘nature first’ approach in development projects, where every effort must be made to avoid causing harm to the existing biodiversity on the site. To successfully meet biodiversity targets, it is necessary to retain and work alongside existing natural features onsite, and only use offsetting as a last resort.

Developers are required to achieve a biodiversity net gain of 10% under the mandatory biodiversity net gain (BNG) legislation. This can be measured using the statutory biodiversity metric. There are three ways for developers to reach the 10% BNG target. Developers have the flexibility to combine all three steps, but it is important to follow the steps in the specified order.

1. Enhance and restore biodiversity within the red line boundary of the development site. This means taking measures to improve the biodiversity onsite.
2. If developers are unable to achieve the full 10% BNG onsite, they have the option to combine onsite and offsite efforts following the mitigation hierachy. This can be done by making biodiversity gains on their own land outside the development site or purchasing offsite biodiversity units from the market.
3. In cases where developers cannot achieve the required biodiversity net gain either onsite or offsite, they must resort to buying statutory biodiversity credits from the government. However, this should be considered as a last resort. The revenue generated from these purchases will be used by the government to invest in habitat creation in England.

The Environment Bill mandates a minimum 10% increase in biodiversity value before granting planning permission. This value is determined using a biodiversity metric established by the Secretary of State and applied nationwide.

Kent faces various land use pressures due to its location near London and as a gateway to Europe. The county experiences significant and unprecedented levels of growth and yet it is also home to over 20,000 species of animals and plants, accounting for nearly 30% of all species in the country.

A study conducted by Vivid Economics on behalf of Natural England examined the economic and developmental impacts of biodiversity net gain. It concluded that the financial viability of housing developments (up to a 20% biodiversity net gain scenario) would not be significantly affected.

Implementing biodiversity net gain onsite can also enhance the value of developments. Proximity to open spaces can increase the value of commercial properties by 3% and housing by 18% according to Kent Nature Partnership's report. Furthermore, promoting biodiversity net gain can create a thriving natural environment teeming with wildlife, providing local communities with opportunities for engagement and reaping the mental and physical health benefits of such connections.

In summary, a biodiversity net gain of 20% or more demonstrates a real commitment to support the nature recovery network, prioritise nature in planning and development, and deliver higher-value homes and buildings.

Typically, the requirements remain the same for both on-site and off-site BNG. Regardless of the location, developers need to:

1. Ensure a mandatory 10% increase in BNG, regardless of its impact on existing biodiversity.
2. Conduct a habitat assessment prior to development and utilise the statutory biodiversity metric to accurately calculate the biodiversity value of habitats before and after the project. This will determine if the 10% BNG target (or more depending on the local authority and your preferences) has been achieved.
3. Prepare and submit a biodiversity gain plan once planning permission has been granted.

Developers may have different obligations when delivering on-site compared to off-site BNG, these obligations include:

1. Management and monitoring, which can be in the form of a habitat management and monitoring plan (HMMP).
2. There may be a legal agreement with a local planning authority (a section 106 agreement) or responsible body (a conservation covenant).
3. There is a requirement to maintain the BNG for a minimum of 30 years which is mandatory for offsite locations but only mandatory onsite for 'significant' onsite habitat enhancements.

All planning applications must include a BNG delivery plan that explains how a site will increase biodiversity after development.

Our BNG solutions have a proven track record of enhancing biodiversity in Kent for over 20 years. We prioritise long-term biodiversity improvement and make the most of your land's potential to benefit nature. Our BNG offsetting solutions are guided by the high integrity principles of Kent Wildlife Trust Group, ensuring maximum benefits for nature are protected in the long run.

Choosing the right habitat. We carefully select habitat interventions that strategically support local nature recovery priorities and contribute to wider conservation goals. Our approach is based on the latest environmental research and aligns with the conservation vision of the Kent Nature Partnership, which aims to create a connected network of natural spaces across the county.

Maximising benefits for nature. Our BNG solutions exceed the minimum requirement by delivering at least a 20% uplift. We avoid offsetting for habitats that are irreplaceable, highly distinct, or important for local species populations. Whenever possible, we create offset solutions that have recognisable wildlife value and the potential to become designated Local Wildlife Sites.

Sustainability. Our habitat management plans prioritize climate resilience and consider how sites can provide additional benefits to communities, such as reducing flood risk, acting as air pollution barriers, and offering recreational opportunities.

We provide a personalised service by taking into account the unique aspects of each project. We customise our service to align with the most suitable offset solution for each development. Our partners BTF have unparalleled expertise in rural land ownership in Kent and the Southeast. Additionally, our collaboration with farmer clusters has given us a deep understanding of land management in the agricultural landscape.

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Kent Wildlife Trust Group can offer a range of services to enable developments to deliver the least environmental impact possible. We have a wealth of experience in delivering habitat improvement projects that maximise the benefits to local wildlife and nature and can provide you with expertise and advice at every step of your project. BNG provides the opportunity to drive best practise development and land management combined with funds to protect and restore nature across Kent.

Kent Wildlife Trust Group are now very well placed to make Biodiversity Net Gain work for wildlife in our county.

• Our Planning team work closely with the planning teams at Kent County Council and will continue to object – where required – to highlight bad planning applications, whilst working with local planning authorities, developers and partners in the Kent Nature Partnership to make sure that BNG is delivered within an effective and a joined up local policy framework that puts nature first.
• Our Consultancy team will work with those developers who pass our due diligence processes to develop BNG plans that have the best chance of driving real gains for wildlife – working in a mission consistent way with Kent Wildlife Trust and investing profits back into nature conservation.
• Our Land Management team will then be able to take on long-term management of any additional land that we can bring into conservation management as offsets are created.