Southwest Environmental Limited

Biodiversity Net Gain

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Biodiversity net gain (BNG) is an approach to development that aims to leave the natural environment in a measurably better state than it was before. It's essentially a way to ensure that new developments don't just minimize harm to nature, but actually enhance biodiversity overall.

How much can I earn from BNG Credits?

Do you need a BNG Assessment? If yes, hit big yellow button and email plans for a quote.

Here's how it Works

1. Assess the existing biodiversity: Before any development takes place, the ecological value of the site is carefully assessed. This includes identifying the types of habitats present, the species that live there, and the overall health of the ecosystem.
2. Calculate the biodiversity loss: The next step is to estimate the impact of the development on the existing biodiversity. This takes into account the area of habitat that will be lost, the fragmentation of habitats, and any potential harm to species.
3. Create a biodiversity gain plan: To achieve BNG, developers must create a plan for how they will compensate for the biodiversity loss. This can involve a combination of measures, such as:

• Habitat creation: Restoring degraded habitats or creating new ones on the development site or elsewhere.
• Habitat enhancement: Improving the quality of existing habitats by planting native trees and shrubs, managing invasive species, or creating wildlife ponds.
• Offsite mitigation: Contributing to biodiversity projects elsewhere, such as supporting existing nature reserves or creating new ones.

    4. Measure and monitor: Once the biodiversity gain plan is implemented, it's important to monitor its effectiveness over time. This ensures that the measures are actually   creating the intended benefits for biodiversity.

The specific requirements for BNG will vary depending on the location and the type of development. However, the basic principles remain the same: to leave the natural world better than we found it.

Here are some of the benefits of BNG

• Protects and enhances biodiversity: BNG helps to ensure that development doesn't lead to a net loss of biodiversity, but actually contributes to its recovery.
• Improves ecosystem services: Healthy ecosystems provide a range of benefits to humans, such as clean air and water, flood protection, and pollination. BNG helps to maintain and improve these essential services. Makes development more sustainable: By considering the impacts of development on biodiversity from the outset, BNG can help to make development projects more sustainable in the long term.
• BNG is still a relatively new concept, but it is gaining traction around the world. As we become increasingly aware of the importance of biodiversity, BNG is likely to become an increasingly important tool for ensuring that development does not come at the expense of our natural world.

How Do I Calcuate Biodiversity net gain (BNG)

There are two tiers of complexity here:

• The Small Sites Metric Calculation Tool . . . and for larger sites;
• The Biodiversity Auditing and Accounting Biodiversity Tool . . . and also;
• The Habitat Condition Assessment Sheets

Case Studies

• Building Back Better: How SWEL Delivered Compliant BNG for a Constrained London SW12 Development
• Turning Pasture into Paradise: How SWEL Achieved 122% Biodiversity Net Gain in Somerset
• Maybe Your Project?

Methodology

Biodiversity Net Gain assessments are conducted in accordance with the Environment Act 2021, utilizing the Defra Statutory Metric. We provide comprehensive UKHab classifications and River Condition Units where required for Statutory BNG compliance.

Technical Guidance: Statutory Biodiversity Net Gain (BNG)

BNG Legislation and Mandatory Planning Requirements

Under the Environment Act 2021, most new developments in England are now legally required to deliver a minimum 10% Biodiversity Net Gain (BNG). This mandatory requirement ensures that development projects leave the natural environment in a measurably better state than before. At SWEL, we support developers through the entire process, from initial planning applications to the final discharge of ecological conditions, ensuring that your project meets the statutory requirements of the local planning authority.

Utilizing the Defra Statutory Biodiversity Metric

The core of any BNG assessment is the Statutory Biodiversity Metric. This tool quantifies the "biodiversity units" of a site before and after development. Our consultants utilize professional UKHab classifications and River Condition Units to establish a robust baseline. Whether your project requires the full statutory version or the Small Sites Metric (SSM), we provide the technical data needed to prove compliance, often as part of a wider Environmental Impact Assessment (EIA) for larger schemes.

Designing the 30-Year Habitat Management and Monitoring Plan (HMMP)

To secure planning consent, developers must submit a Biodiversity Gain Plan supported by a Habitat Management and Monitoring Plan (HMMP). This document outlines how the 10% gain will be maintained for at least 30 years. We work closely with design teams to integrate high-value habitats into the site layout, such as wildlife ponds or native woodland, ensuring these measures are sustainable and manageable, often linked to environmental permitting requirements for specialized management activities.

Off-site Offsetting and Biodiversity Credits

Where on-site delivery is not feasible due to space constraints, particularly in urban infill projects, off-site mitigation or statutory biodiversity credits may be required. We assist landowners in identifying BNG credit opportunities and developers in securing necessary offsets. Our consultancy provides technical evidence for Conservation Covenants and Section 106 agreements, ensuring that off-site enhancements are legally secured and accurately mapped using our proprietary infrastructure and catchment data.

Technical Evidence for Professional Planning Statements

Securing BNG approval is now a fundamental pillar of any successful Planning Statement. Our "True Data" approach provides the scientific foundation needed to satisfy planning officers and statutory consultees like Natural England. With over 900 projects across the UK, SWEL brings the technical authority and ecological expertise required to navigate the complexities of BNG, ensuring that your development contributes to national nature recovery while meeting all regulatory deadlines.