BNG Masterclass for Infrastructure Developers

Key takeaways: Understanding BNG in real-world projects

Infrastructure developers have some months before they will be required to answer to 10% biodiversity net gain (BNG) mandates of the UK’s Environment Act 2021.

That makes now a great time to gain an understanding of what will be expected in 2025.

Milestone Infrastructure Director of Sustainability Edward Godsiffe joined AiDash Senior Ecologist Hannah Williams to deliver a live-event Masterclass for Infrastructure Developers at UKREiiF 2024. They looked at the need for BNG, what BNG does, and ways to approach BNG mandates. They also provided best practice insights from a recent infrastructure project.

Read on for a few key Masterclass takeaways.

Takeaway 1: Biodiversity net gain is biodiversity through a new lens.

AiDash Senior Ecologist Hannah Williams walked attendees through the need for a clear-eyed look at biodiversity.

“We’re in a climate crisis right now, but we are equally within a biodiversity crisis. And the UK, unfortunately, performs really poorly,” she explained, citing several concerning statistics:

State of Nature report in 2023 identifies the UK as one of the most nature-depleted countries in the world.
Since the 1930s the UK has experienced a 97% decrease in lowland meadows.

Amid this frightening rate of decline, “we cannot continue to do things the way that we have done,” she said. “And development provides a key role in helping us on that biodiversity journey.”

While developers have started to improve on traditional environmental/biodiversity impacts, bringing those rates down, there is an urgency now to go beyond just reaching zero impact. “We have to move beyond that because … we’re on a declining trajectory here,” she added.

Enter UK biodiversity net gain regulations.

Takeaway 2: UK Environment Act 2021 challenges developers for improvements, but points to new opportunities

Although standard developers and small site developers have been required to comply with Environment Act 2021 since February 2024 and April 2024, respectively, infrastructure developers have had more time to adjust with their mandatory compliance expected in 2025.

The Environment Act generally requires that developers:
• Ensure each development project’s habitat achieves 10% biodiversity net gain: that is, 10% better than it was before the project commenced.
• Put plans in place to maintain that improvement for 30 years.
• Use the Defra Statutory Biodiversity Metric tool to measure and plan for BNG gains and losses.

Your local planning authority (LPA) requires you to create a BNG baseline of your development property and use the tool to assess against your design and plan for post-development biodiversity. Expect to work closely with your LPA to complete required documents to assemble a successful planning application.

It pays to use the Statutory Biodiversity Metric tool “often and early, to make sure you’re on track,” Williams advised. She extended that advice to even before land purchase to help determine whether development plans that meet BNG guidelines are feasible.

Mitigation hierarchy

Biodiversity net gain is designed to enforce mitigation hierarchy to limit effects on the environment, Williams explained. Developers are encouraged to create plans with the least impact possible, considering mitigation hierarchy’s 4 levels:

Avoid — prevent impact.
Minimize — reduce impact duration or severity.
Restore — make improvements to stabilize or improve.
Offset — find places on- or off-site to compensate for unavoidable impacts.

Challenges and opportunities

Williams acknowledged challenges and concerns voiced by developers during the live masterclass, including:

Cost — expense BNG planning and application process.
Timing/delays — application processes may move slower than expected due to under-resourced LPAs.
Land constraints — finding available parcels.
Lack of ecologists — may be a wait to engage an ecologist in assessment and planning.
Complex legal agreements — BNG complexities mean review for sound legal approach is necessary.

“Making sure that we can deliver actual multiple benefits on land, not just by BNG, is going to be a massive question for a lot of developers and local planning authorities to work out together,” said Williams.

But she also pointed to opportunities:

Revenue — biodiversity units (BUs) can be created by improving on-site and/or off-site land parcels, and allowing others to purchase those BUs as biodiversity credits.
Green legacy — securing green access, enhanced placemaking, improved health, and natural capital.

To provide a real-world view of these BNG considerations, Ed Godsiffe, Sustainability Director for Milestone Infrastructure, offered the following case study of a recent highway project.

Takeaway 3: Best practice for real-world applications: plan early, plan often

Milestone is the largest provider of highway services in the UK, managing more than 50,000km of highway across England as well as delivering civil engineering construction projects. Last year, the company delivered a highway improvement project for England’s Peterborough City. This $7.5 million, 12-month project was enacted to deliver capacity to the existing road network. Milestone was charged with adding a northbound lane to an existing highway as well as a new footbridge that would accommodate the new lane.

Godsiffe explained that space challenges were in the forefront of initial design planning. “Anything we’re doing to improve or enlarge the existing highway — you are ultimately taking from what is a limited space,” he said.

In addition, Godsiffe noted that any off-site improvement opportunities to compensate for the highway development were limited to what land Peterborough City actually owns.

And the Peterborough City Council added a degree of difficulty halfway into the planning of the project: It requested that Milestone step beyond the government mandated 10% BNG and deliver 20% BNG.

“We actually had to extend the red-line boundary of the project to allow us to take more land into the project to deliver biodiversity improvement … to get us towards that 20%,” he explained.

By project’s end, Milestone was able to deliver only 13% BNG, which was acceptable as the 20% was an ask, not a contractual element.

“We didn’t quite get there, but we learned a huge amount that we’ve taken forwards into subsequent projects,” he said. “One of the key things we learned: To deliver 20% [BNG], you’re very rarely going to be able to do that within just that single project’s red-line boundary. You need to start looking broader —across multiple projects, across the whole estate, across different land holdings — to allow that internal offsetting to get you towards that 20%.”

And he seconded Williams’ advice about using the Statutory Biodiversity Metric tool early and often. “Get in [to BNG planning] as early as possible. Be proactive with it. There’s a lot of different ways of achieving the outcome.”

For more about what infrastructure developers need to know about BNG, view the full masterclass here.

For more about how AiDash BNGAI™ can streamline and ease the BNG planning and the BNG application process, view our BNG compliance whitepaper.

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