Understanding Biodiversity Net Gain
Biodiversity Net Gain (BNG) is now a legal requirement across England, transforming how development and land use are approached. For landowners, especially those in rural and peri-urban areas, the BNG framework opens new opportunities and responsibilities.
The core principle is simple: any property development must leave biodiversity in a measurably better state than it was before. This is calculated using a statutory biodiversity metric that assesses the pre-development biodiversity value and the proposed post-development enhancements.
As part of the Environment Act, mandatory biodiversity net gain applies to most major developments. Local planning authorities require a biodiversity gain plan, which details how projects will achieve at least a 10% net gain in biodiversity. The biodiversity baseline is crucial, determined by measuring the existing habitat and ecological value of the development site before any work begins.
The Role of Landowners in the New Legal Landscape
Landowners now play a pivotal role in helping developers meet BNG requirements. This often involves offering land for off-site biodiversity units where on-site gains cannot be fully achieved. Land that provides suitable habitat creation and management can be registered as a biodiversity gain site on the National Biodiversity Gain Site register. This is where landowners can directly contribute to sustainable development practices while establishing long-term revenue streams.
Providing biodiversity units through habitat banks or individual agreements allows landowners to sell units to developers in need of off-site gains. These units are calculated using standardised biodiversity metrics, ensuring consistency in how biodiversity value is assessed across different sites. This helps developers comply with the mitigation hierarchy while ensuring that real ecological value is delivered.
Off-Site Biodiversity Units and Credits
Off-site biodiversity is a key aspect of the BNG strategy, particularly for projects with limited space or ecological capacity on site. In such cases, developers must seek off-site biodiversity gains to meet their net gain obligations. Landowners offering off-site BNG options must enter into legal agreements, such as conservation covenants with a responsible body. These ensure long-term habitat management and protection.
In circumstances where neither on-site nor off-site gains are feasible and no private marketplace BNG options are available, statutory biodiversity credits may be purchased by developers from Natural England. However, this is intended as a last resort in the biodiversity gain hierarchy.
Off-site habitat creation led by private landowners remains a preferred option because it often delivers more targeted and locally beneficial outcomes.
Legal Framework and Key Considerations
The legal framework underpinning BNG includes several key components that landowners should be aware of. The Environment Act, biodiversity gain site register, and statutory biodiversity metric provide the foundation. Any biodiversity enhancements offered as part of a gain plan must be secured by a legal agreement (e.g. Conservation Covenant) that demonstrates a long-term commitment to habitat enhancements and maintenance.
A responsible body, such as a local authority or conservation organisation, oversees compliance with conservation covenants. For landowners, this means a clear and enforceable obligation to manage and maintain the habitat to the agreed standard. These measures provide developers and planning authorities with the assurance they need to approve projects with confidence.
Developers purchasing biodiversity units must provide full details of the purchase agreement in a Biodiversity Gain Plan. Local planning authorities will scrutinise all biodiversity gain plans during the planning permission process. This includes evaluating whether the unit provider has satisfied all the necessary legal requirements and due diligence checks to operate as such.
Opportunities for Landowners and Land Managers
For landowners and land managers, BNG can offer a valuable and sustainable income stream. Habitat banks and direct provision of biodiversity units can become a central part of a land management strategy. By considering BNG habitats on their land, landowners can market their sites to developers undertaking major developments, including nationally significant infrastructure projects. This allows landowners to secure lucrative and guaranteed long-term income on their land; this income is well in excess of usual yield-based incomes and completely independent of the impacts of variables like weather that usually add uncertainty to yield-based income streams.
Engaging with BNG on your land also aligns with broader goals of enhancing habitats and improving ecological services. Off-site habitat creation not only meets the requirements of biodiversity net gain but also contributes to improved soil health, water retention, and climate resilience. These benefits enhance the long-term health of the land while supporting the natural environment.
Investing in suitable habitat creation is a tangible way to support wildlife habitats and protect the ecological value of rural and semi-rural areas. Whether restoring hedgerows, rewilding wetland corridors, or reinstating grassland, landowners can tailor their biodiversity gain strategies to local environmental needs and conditions.
Navigating the Planning System and Gaining Approval
To participate effectively in the BNG framework, landowners must understand how to work within the planning system and/or with a responsible body. Local authorities and responsible bodies are looking for clarity, accountability, and long-term ecological viability in any proposed off-site biodiversity unit. Civity guides landowners and land managers through this process from start to finish.
Civity are experts at producing site-specific and robust Habitat Management and Monitoring Plans (HMMP). An effective HMMP is vital to clearly demonstrate how the site will deliver net gain through habitat management. It must reference the biodiversity baseline, specify habitat types, and detail long-term management and monitoring plans. This document is essential to achieving registration on the BNG register and ensuring the responsible delivery of biodiversity gain.
The integration of BNG into the planning process means that all stakeholders—developers, landowners, local authorities, and conservation bodies—must collaborate more closely. By aligning the goals of development with nature conservation, the system aims to create more resilient and biodiverse landscapes.
Conclusion: The Future of Land Use and Biodiversity Net Gain
The introduction of mandatory biodiversity net gain is reshaping the way land is managed, developed, and protected in England. Landowners are no longer on the periphery of the planning system but are now essential partners in delivering ecological improvements. The new legal landscape offers not only regulatory challenges but also exciting opportunities to enhance biodiversity, support sustainable development practices, and create lasting environmental and economic value.
By providing biodiversity units, engaging in suitable habitat creation, and managing land for ecological value, landowners are helping to meet the goals set out in the Environment Act and the wider environmental agenda. As the system matures, the biodiversity gain site register, statutory biodiversity credits, and conservation covenants will continue to evolve, offering new mechanisms for landowners to contribute to and benefit from the biodiversity net gain system.
For landowners committed to sustainable and responsible land management, this is a pivotal moment. Civity is a specialist biodiversity consultancy helping developers and landowners navigate Biodiversity Net Gain requirements with expert guidance and strategic support. With careful planning, expert advice, and a commitment to ecological value, BNG can become a central part of your land management strategy and a legacy for the natural environment.
