When to use Off-Site Biodiversity Net Gain (and deliver better outcomes than on-site)
Should BNG be delivered on-site or off-site? Explore why off-site biodiversity units can often achieve better outcomes for nature and development compliance.
With off-site biodiversity units now widely available through providers like Integrated Land Management, developers have more flexible options for achieving BNG compliance without redesigning their entire site layout.
Recent reports of on-site Biodiversity Net Gain (BNG) projects failing within years of establishment highlight a critical consideration for developers: sometimes off-site BNG isn’t just an alternative – for some schemes it can be the superior choice for delivering reliable biodiversity outcomes.
While on-site habitat creation might seem like the obvious solution, and under the right circumstances it can be an excellent solution, emerging evidence suggests that off-site biodiversity units can often deliver more robust, strategically valuable results that actually support nature recovery.
Understanding the Limitations of On-Site BNG
We’ve seen emerging reports of on-site BNG projects that haven’t been efficiently designed, managed, or monitored, leading to ecological failure within years of establishment. These biodiversity net gain failures often stem from fundamental constraints that off-site solutions can address more effectively.
Competing Development Priorities: Biodiversity can often become a final thought on development sites – squeezed into leftover spaces after the main development priorities have been addressed. This approach compromises the quality and connectivity of habitats, making it more difficult to achieve meaningful biodiversity net gain.
Limited Ecological Expertise: Many developers lack the specialist knowledge needed for long-term habitat management. Without the proper understanding of local ecology, soil conditions, and species requirements, even well-intentioned on-site BNG projects can fail to establish or maintain themselves over the required 30-year period.
Fragmented Habitat Delivery: Small, isolated habitat patches on development sites may struggle to support viable wildlife populations or connect to wider ecological networks. This fragmentation reduces the overall effectiveness of biodiversity offsetting efforts.
Benefits of Off-Site BNG for Developers
Off-site biodiversity net gain offers several advantages that can deliver more reliable and strategically valuable results for nature recovery:
-
Off-site units can be allocated in locations specifically chosen for their ecological potential - areas with suitable soils, hydrology, and connectivity to existing habitats. This strategic approach means habitats are more likely to establish successfully and support thriving wildlife populations over the long term.
-
Unlike on-site delivery where BNG is often squeezed around development constraints, off-site units are designed with biodiversity as their main priority. This means larger, more connected habitats that can support diverse species and ecological processes – exactly what effective biodiversity net gain should achieve.
-
With the introduction of Conservation Covenants and Responsible Bodies, off-site BNG is often more thoroughly regulated than on-site alternatives. This additional oversight helps ensure projects are properly designed, implemented and monitored for the full 30-year commitment period, reducing the risk of biodiversity net gain failures.
-
Off-site unit providers like Integrated Land Management bring dedicated ecological expertise and proven land management experience. We understand the practical realities of habitat creation and have established systems to ensure long-term success, something that’s often missing from on-site BNG projects.
When Off-Site BNG is the Better Choice
Consider off-site biodiversity net gain when:
Site conditions aren’t suitable for the habitats you need to create according to the biodiversity metric
Space constraints would result in small, fragmented habitats that can’t support viable ecosystems
You lack long-term management capacity for ongoing habitat maintenance and monitoring
Strategic connectivity could be better achieved through larger, connected off-site habitats
Combining On-Site and Off-Site BNG for Optimal Results
The most effective BNG strategies often combine both approaches strategically:
On-site delivery for smaller interventions that enhance the immediate development area and provide local community benefits
Off-site biodiversity units [link to sites] for larger biodiversity gains that require specialist habitats or strategic positioning within nature recovery networks
This hybrid approach allows developers to maximise both local environmental benefits and broader ecological impact while ensuring compliance with biodiversity net gain requirements.
Off-Site BNG Units with Integrated Land Management
At ILM, we specialise in delivering off-site BNG that works in the real world. Our comprehensive approach ensures your biodiversity net gain obligations are met effectively:
-
Our biodiversity units are positioned in locations chosen specifically for their ecological potential, ensuring habitats establish successfully and support thriving wildlife populations.
-
Our units are legally secured and registered, ensuring your BNG compliance is straightforward and secure.
-
We provide comprehensive legal protection through Conservation Covenants and Section 106 Agreements, guaranteeing your biodiversity net gain commitments are secured for the full 30-year period and will be properly managed and monitored.
-
Our detailed HMMPs ensure consistent delivery of biodiversity outcomes throughout the commitment period.
-
When you work with ILM, you deal directly with our experienced team who understand both the regulatory requirements and practical realities of delivering successful biodiversity net gain.
BNG Advice for Developers and Planners
Successful biodiversity net gain depends on choosing the right approach for your specific site and circumstances. While on-site delivery can work well in suitable locations, off-site BNG often provides a more reliable path to achieving your biodiversity obligations while supporting genuine nature recovery.
The key is working with experienced providers who can guide you through the options and help you make informed decisions based on ecological potential and regulatory compliance rather than just convenience.
Ready to explore off-site units for your project? Our team of BNG experts is here to help you navigate the biodiversity metric, understand trading rules and secure the right units to meet your planning requirements.
FAQs
-
While unit costs vary, off-site BNG can provide better value when you factor in design, implementation, monitoring and long-term management costs. You also reduce the risk of costly failures that can occur with poorly planned on-site projects.
-
Look for BNG units providers like Integrated Land Management with registered and legally secured Gain Sites, comprehensive management plans and transparent reporting systems.
-
Yes, well-positioned off-site units can support local nature recovery networks and biodiversity action plans more effectively than fragmented on-site habitats, creating genuine landscape-scale benefits.
