Biodiversity Net Gain in Greater Manchester: What Developers Need to Know

Biodiversity Net Gain in Greater Manchester (BNG) is a relatively new policy that requires developers to ensure their projects enhance biodiversity, leaving the natural environment in a better state than before. While its goals are commendable, for many developers BNG represents yet another hurdle in an already challenging planning process. Resolve can support developers in meeting these requirements efficiently, even in the face of mounting pressures. In Greater Manchester, a region committed to sustainability, BNG has become a key consideration for development projects of all sizes. The mandatory requirement for a 10% net gain, adds a significant layer of complexity to development projects. This blog will explore the intricacies of BNG, including its purpose, the stakeholders involved, and its implications for small developers. We will also discuss the challenges in achieving BNG along side other sustainability goals.

What you need to know about the power of Biodiversity Net Gain?

Biodiversity Net Gain refers to measurable improvements in biodiversity resulting from development. It is assessed by comparing the biodiversity value of a site before and after development, using tools like the Defra Biodiversity Metric. Developers are required to ensure that their projects achieve at least a 10% net gain compared to the baseline biodiversity value. This can be achieved through on-site enhancements, such as planting native species, or off-site measures, like purchasing biodiversity credits.

To achieve BNG, developers follow a structured process:

• First, a baseline assessment determines the biodiversity value of the site.
• Next, potential impacts are measured, and measures to mitigate or offset those impacts are identified.
• Finally, enhancements are planned, implemented, and monitored to ensure compliance with the net gain requirements.

These calculations consider distinct habitat types such as areas of land, hedgerows, and water habitats. Each is assessed based on factors like size, condition, and ecological importance. Although it would be ideal, we do not count the plants and animals, numbers, or species present during a BNG calculation; instead, the habitat calculations serve as a proxy or indicator for the biodiversity that will thrive there. Better habitats inherently support better biodiversity, ensuring ecological improvements are meaningful. BNG is not just about compliance; it is a commitment to leaving the environment better than before, fostering long-term ecological benefits.

Why Was BNG Introduced?

BNG was introduced as part of the UK government’s efforts to address the alarming decline in biodiversity. The policy is rooted in the principle that economic development and environmental stewardship can coexist. The Environment Act 2021 makes BNG mandatory for most planning applications in England starting in November 2023. Its primary goals are:

1. To reverse decades of biodiversity loss and restore ecosystems.
2. To ensure sustainable development that benefits both people and nature.
3. To create a standardised framework for biodiversity improvements, making it easier for local authorities to evaluate planning applications.

In Greater Manchester, a region with ambitious sustainability targets, BNG aligns with broader goals, such as achieving carbon neutrality by 2038. By embedding biodiversity considerations into the planning process, BNG fosters resilience against climate change and enhances the quality of life for local communities.

BNG: Who Needs to Be Informed?

BNG affects a broad range of stakeholders involved in development and urban planning. Developers, architects, planners, and local authorities all play vital roles in its implementation.

For developers, understanding BNG is crucial to avoid delays or rejections in the planning process. Architects and planners must incorporate biodiversity measures into their designs, ensuring compliance with BNG requirements. Local authorities oversee the enforcement of these requirements, ensuring that developments align with broader sustainability objectives. Even property investors have a vested interest, as sustainability credentials increasingly influence property values.

Community groups and environmental advocates also have a stake in BNG, as it directly impacts the quality of local ecosystems and green spaces. For all these stakeholders, BNG represents an opportunity to collaborate on projects that balance economic growth with environmental protection.

Although a qualified professional with expertise in conducting the assessment must be appointed, developers are increasingly turning to sustainability consultants not only to carry out the required BNG assessment but also to provide guidance on enhancements needed to maximise the site’s ecological value.

How Biodiversity Net Gain Impacts Small Developers in Greater Manchester

For small developers, including those working on single properties or minor housing developments, BNG introduces new challenges and opportunities. The requirement to achieve a 10% net gain in biodiversity may seem daunting, especially for projects with limited budgets and space. However, it is possible to meet these requirements with careful planning and innovative solutions.

Small developers working on new builds must integrate biodiversity enhancements into their plans. Simple measures, such as planting native trees, creating wildflower meadows, or installing green roofs, can contribute significantly to the net gain. These measures not only enhance biodiversity but also improve the aesthetic appeal of the development, potentially increasing property values. These must also align with each planning authority’s specific requirements.

While refurbishments may not always require a full BNG assessment, incorporating biodiversity measures can still offer advantages. Adding bird or bat habitat, or pollinator-friendly plants can improve public perception of the project and streamline the planning process. Even small enhancements can make a big difference, demonstrating a commitment to sustainability.

Challenges for Small Developers

The primary challenges small developers face include space constraints, financial limitations, and the complexity of BNG assessments. Achieving the 10% net gain on sites with limited room for significant enhancements can be particularly difficult, particularly for developments on greenfield sites. These sites often have high baseline biodiversity values. In such cases, off-site measures, such as purchasing biodiversity credits, may be necessary. Balancing these requirements with other planning priorities, such as housing density and energy efficiency, demands careful coordination and expert guidance. However, a skilled architect or, preferably, a sustainability consultant will have a playbook of tried-and-tested ideas to achieve BNG on site affordably and without significantly disrupting development plans

How BNG Aligns with Greater Manchester’s Greater Sustainability Goals

Achieving BNG is just one aspect of sustainable development. Developers must also consider other criteria, such as carbon reduction, water management, and community benefits. For example, incorporating sustainable drainage systems (SuDS) can help manage water runoff while enhancing biodiversity. Similarly, energy-efficient building design which Resolve is experts in can contribute to sustainability goals without compromising green space.

If we had to point out some concerns with their BNG assessment, their reliance on habitat calculations as proxies for biodiversity, may be number one. While these proxies provide a structured and measurable framework, they oversimplify the complexity of ecosystems, ignoring species-specific needs and interactions. This can lead to outcomes that appear beneficial on paper but fall short of genuine ecological improvements.

Another concern is the potential for off-site measures, such as biodiversity credits, to become a loophole. While these credits provide flexibility for large developers, they can shift the burden of conservation away from development sites, creating “greenwashing” opportunities where biodiversity losses are inadequately compensated. This undermines the principle of local ecological enhancement. Small developers don’t have this luxury, BNG assessments present financial and logistical challenges. The process can be expensive and complex, often requiring specialist consultants. These risks creating a barrier to entry for smaller projects, disproportionately favouring larger developers with greater resources. Arguably counter intuitive to economic sustainability and a just transition.

The 10% net gain target, though well-intentioned, may be insufficient in areas where biodiversity is already severely degraded. Without robust enforcement and monitoring, there is a danger that BNG assessments could prioritise compliance over genuine ecological recovery, limiting their long-term impact.

Achieve BNG Success with Expert Guidance from Resolve Sustainability Consulting

Our team supports developers, especially smaller ones with limited resources, in navigating BNG requirements. We offer end-to-end services to ensure compliance and maximise biodiversity benefits.

Starting with a baseline site assessment using the Defra Biodiversity Metric, we calculate existing biodiversity value and create a tailored plan to achieve net gain. This will include on-site measures like wildlife corridors or planting native vegetation.

We focus on cost-effective implementation, balancing BNG requirements with budget constraints and local planning authority expectations. Our consultancy provides innovative, expert-driven strategies to address these challenges while aligning biodiversity goals with broader sustainability objectives. If you have an upcoming development or are preparing to submit a planning application, we encourage you to get in touch. BNG can be addressed alongside resource management and low-energy building design, ensuring a holistic approach to your project.

From Challenge to Success: BNG on a Greater Manchester Development

Imagine a single-house development on an infill site in Greater Manchester. The site was in the early stages of rewilding, with some native species, such as brambles. One-third of the land was to be occupied by the footprint of the new building. Our team conducted a baseline assessment and identified opportunities to improve the architect’s proposed landscape design, including species-specific native hedgerows and the creation of wildflower and heath habitats.

Although the original plans showed a 41% reduction in habitat units and a 100% loss in hedgerow units, our revised landscape plans resulted in a 32% increase in habitat units and a 360% increase in hedgerow units. The BNG assessment was completed alongside a report on the findings and best-practice installation methods in accordance with Trafford Planning Authority.