Biodiversity Net Gain : Reflecting on Year One

Written by Maisie Mckenzie, Biodiversity Manager

One year on, the UK embarked on a transformative path toward environmental sustainability with the introduction of Biodiversity Net Gain (BNG). A policy requiring all new developments to deliver a 10% measurable improvement in biodiversity, BNG represents a monumental shift in how we approach urban growth and construction. For developers, planners, and communities alike, it offers an opportunity to integrate nature into the fabric of modern life. But as with any significant change, its first year has revealed both remarkable potential and undeniable challenges.

BNG aims not only to offset the ecological impacts of new developments but to enhance the natural world for future generations. By focusing on habitat creation, long-term conservation, and sustainable design, it provides a blueprint for transforming our built environment into a network of nature-rich communities. However, turning this vision into reality has proven to be a complex task, particularly for local planning authorities (LPAs) and developers leading the charge. 

Local planning authorities are key to BNG’s implementation, but the first year highlighted the opportunity for growth in this area. Before the statutory requirement, 92% of LPAs did not have a dedicated policy on biodiversity net gain. Since then, many have been working diligently to build the capacity, expertise, and resources needed to meet these new expectations.

Studies showed that 85% of LPAs felt they would benefit from having more ecological professionals on staff to better manage the workload. This variation in resources has led to differences across regions, with some authorities well-equipped to assess BNG applications effectively while others work towards meeting standards. Even with the involvement of ecological experts, their varying requirements can sometimes create challenges and extend timelines for developers.

Streamlining and standardising these processes will be crucial moving forward. Without it, LPAs risk becoming the bottleneck in a system designed to accelerate ecological restoration. 

The introduction of BNG has presented significant challenges for developers. From identifying which parts of a project should incorporate biodiversity measures to meeting the 10% improvement target and accounting for long-term monitoring costs, its complex requirements have sparked widespread industry debate. 

However, by embracing the Ten Core Principles of BNG and integrating biodiversity enhancements into project designs, developers have the opportunity to create developments that benefit both nature and society for generations to come.

Here’s a summary of the ten core principles of Biodiversity Net Gain (BNG):

1. Apply the Mitigation Hierarchy: Prioritise avoiding and minimising biodiversity impacts. Only compensate for unavoidable losses as a last resort, ensuring gains elsewhere if necessary.

2. Avoid Losing Irreplaceable Biodiversity: Prevent impacts on biodiversity that cannot be offset or replaced.

3. Be inclusive and equitable: Engage stakeholders early and involve them in designing, implementing, and monitoring Net Gain efforts. Share benefits fairly.

4. Address Risks: Mitigate uncertainties and risks to achieving Net Gain by using contingency measures and accounting for time delays between losses and gains.

5. Make a Measurable Contribution: Ensure biodiversity gains are measurable and contribute to nature conservation priorities.

6. Achieve the Best Outcomes for Biodiversity: Use robust evidence and local knowledge to make decisions that deliver the greatest benefits for biodiversity, including enhancing habitats and ecological connectivity.

7. Be Additional: Deliver outcomes that go beyond existing obligations and would not have occurred otherwise.

8. Create a Net Gain Legacy: Ensure long-term benefits by planning for adaptive management, securing funding, and designing resilience to external factors like climate change.

9. Optimise Sustainability: Prioritise biodiversity gains while maximising broader environmental and societal benefits.

10. Be Transparent: Communicate Net Gain activities openly and share learnings with stakeholders in a timely manner.

Another challenge is the need for clear systems to monitor and maintain these ecological enhancements over time. While projects may meet the initial requirements for approval, ensuring compliance over a 30-year period requires thoughtful planning and reliable follow-up. With proper systems in place for monitoring and enforcement, we can help preserve biodiversity gains and uphold the goals of this policy. 

On top of this, achieving BNG has required significant financial investment. Costs associated with ecological surveys, habitat management, and ongoing monitoring have increased, encouraging careful budget planning in an industry navigating economic challenges. While this has led to a slight decrease in planning applications over the past year, it presents an opportunity to focus on high-quality, sustainable projects.

BNG offers a practical pathway to boost biodiversity through habitat creation and enhancement. By integrating sustainable design principles into buildings and hardscape features, it provides effective solutions to address broader environmental challenges, making meaningful progress well within reach.

For example, permeable pavers promote sustainable landscaping by reducing water runoff, mitigating soil erosion, and lowering flood risks in urban areas—an essential element of sustainable developments. Similarly, rainwater harvesting systems enable the collection and reuse of rainwater for everyday tasks such as flushing toilets, running washing machines, and watering gardens. 

Innovations like eco-habitats provide developers with opportunities to deliver further species focused biodiversity improvements by creating protected spaces that support local wildlife, including birds and bats. These solutions not only help meet compliance requirements but also bring meaningful benefits to communities.

Beyond the logistical and financial hurdles, it’s important to remember why BNG exists. With 16% of UK species threatened with extinction, enhancing biodiversity isn’t just a regulatory checkbox—it’s an ethical imperative. 

The first year of BNG implementation has been far from smooth, but it has laid the groundwork for a brighter future. The second year is an opportunity to learn from the challenges, close the knowledge gaps, and build momentum. Developers should increasingly turn to tools, resources, and innovative products specifically designed to meet BNG requirements while maximising project value. 

Want to stay ahead of the curve and broaden your expertise in biodiversity? Register your interest in our Enhancing Biodiversity in the Built Environment CPD session. These sessions are designed to equip planners, developers, and other industry stakeholders with the knowledge and tools needed to confidently achieve BNG targets, streamline processes, and integrate sustainable practices into projects. 

Sign up for a biodiversity CPD session today using the form below and help shape a future where urban development and nature thrive together: