The Environment Consultant

Biodiversity Net Gain (BNG) is an approach to development and land use that leaves biodiversity in a better state than before. It requires that any loss of natural habitat or biodiversity as a result of a project must be more than compensated by measurable improvements elsewhere.

At its core, BNG is not just about avoiding harm – it is about actively enhancing ecological value. This is a significant shift from traditional impact mitigation, pushing stakeholders toward regenerative environmental practices.

In practical terms, BNG involves:

• Measuring baseline biodiversity using a standard metric (e.g., the UK’s Biodiversity Metric).
• Minimising impacts on-site as much as possible.
• Compensating for residual loss with habitat creation or enhancement.
• Demonstrating an overall net positive outcome, usually expressed as a percentage gain (e.g., 10% net gain in biodiversity).

UK as BNG Champion

The United Kingdom (UK) has been a global pioneer in adopting BNG through both policy and law. As of February 2024, BNG became mandatory in England under the Environment Act 2021 (inserted by Schedule 14) for most new developments. Key requirements include:

• A minimum 10% net gain in biodiversity.
• Use of a standardised biodiversity metric.
• A minimum of 30 years’ management and monitoring of BNG sites.
• A preference for on-site gains, though off-site and statutory biodiversity credits are permitted.

Several local authorities in the UK began requiring BNG on a voluntary or policy-driven basis even before national enforcement, leading to the development of best practices, data systems, and a growing marketplace for biodiversity units.

Voluntary BNG

Although mandatory only in the UK, the voluntary adoption of BNG is gaining traction worldwide as a best practice model, particularly in sectors like infrastructure, mining, and urban planning. BNG offers:

• A structured, quantifiable framework to measure and report ecological outcomes.
• Improved outcomes for biodiversity conservation in areas where environmental regulations are limited or weak.
• Strong alignment with global frameworks such as the Kunming-Montreal Global Biodiversity Framework, which calls for halting biodiversity loss and restoring degraded ecosystems by 2030.

Countries such as Australia, Canada, the Netherlands, and South Africa have adopted similar “no net loss” or net gain principles in regional planning and conservation banking, though these vary in scope, enforcement, and technical methodology.

Benefits of BNG for Projects and Stakeholders

From a project delivery perspective, BNG:

• Reduces long-term ecological risks, enhancing regulatory and community trust.
• Creates new revenue streams through habitat banking and conservation finance.
• Aligns with corporate sustainability goals, particularly for ESG reporting and nature-related financial disclosures (like TNFD).
• Encourages early integration of ecology into project design, reducing late-stage delays and costs.

The Need for Policy Integration

For BNG to be impactful globally, it must evolve from a voluntary tool to a formalised policy mechanism. This requires:

1. Standardisation of metrics: Cross-border compatibility and transparency in how biodiversity is measured.
2. Legal enforcement: Incorporation into national planning laws or environmental impact assessment frameworks.
3. Incentives for developers: Tax benefits, credits, or planning permissions that reward positive biodiversity outcomes.
4. Capacity building: Investment in training ecologists, local authorities, and planners in applying BNG principles effectively.
5. Data and monitoring infrastructure: Transparent systems for tracking long-term biodiversity outcomes.

The challenge lies in balancing ecological ambition with practical delivery. Where governance is strong, BNG can be mandated. Where governance is weaker, voluntary frameworks and market mechanisms may pave the way.

BNG represents a paradigm shift in how we think about biodiversity and development – not as opposing forces, but as interdependent outcomes. For ecologists and environmental professionals, this is a chance to lead a transformation in project design, policy, and land use planning.

While BNG is now a legal requirement in England, it is also a visionary tool for any country seeking to harmonise economic growth with ecological resilience. Whether used voluntarily or regulated nationally, BNG sets a new bar for responsible development, and for restoring nature in the process.