Skip to main content
24.05.2023

10% biodiversity net gain: current issues facing the sector

“You’re not getting rid of BNG mate!”
“My hope is that wherever I’m going for a run, I’m swallowing flies”

These are just some of the quotes from the excellent panellists and speakers at the BNG conference earlier this year. A day of fascinating and thought provoking topics left the room feeling both inspired to do better but also gloomier around the limitations of the current framework. The mandatory 10% biodiversity net gain comes into force in November 2023 but it was clear that the industry is not quite ready for it yet. Here we take a brief look at some of the concerns raised: 

- Lack of expertise / uncertainty. The secondary legislation nor the detail required (e.g. for phased developments and exemptions) remains yet to be seen and the guidance published in February left much to be desired. Meaning discussions need to be had by all now to ensure consistency in application when November approaches. Lawyers are voicing uncertainty around conservation covenants, ecologists were still getting their heads around Metric 3.0 (although the new metric 4.0 has since been published), a third of local authorities do not have an in-house ecologist and are concerned about the enforcement of BNG and councillors are unsure of the unintended consequences on other priorities.

- Inconsistency in mitigation hierarchy. The mitigation hierarchy in the guidance (i.e. on site gains preferred over off site gains, and off-site gains should be provided locally) is not required by the Environment Act 2021 which is expected to lead to future litigation or appeals.

- Competing priorities. Evidence suggests that a 10% increase is the minimum required to ensure that a net loss in biodiversity would be avoided. However Councillors and other stakeholders are already concerned of the unintended consequences (particularly where local authorities are requiring 20% BNG) on other key priorities such as affordable housing, open space etc. And this is before even considering the circular economy and how to achieve all of this ‘sustainably’ or, where relevant, the difficulties and costs involved in preparing brownfield sites for development.

- Under resourced enforcement teams. Studies on BNG from around the world have all shown that a proper monitoring enforcement regime is vital (and that third party auditing works best) if the long term 30-year maintenance period is to work. Not only are many LPAs under-resourced, but LPAs cannot enforce against landowners delivering off-site gain where the LPA isn’t a party to the conservation covenant.

- Skills gap. There appears to be a skills shortage particularly for those who would be managing BNG sites on the ground. The skill set we’ve typically seen has historically been for manicured amenity spaces which is different to that where managing land for nature for a long term (at least 30 years).

- Lack of cohesion between BNG, nature recovery and green infrastructure plans. Ideally these need to be pulled together strategically to deliver the most effective outcomes.

Clearly not all of the above will be solved before November 2023, but the industry is grappling (at speed) with the pending BNG framework.

How we can help

Irwin Mitchell has recently provided strategic advice on and negotiated a bespoke section 106 planning agreement for a new habitat bank to provide habitat units for the benefit of planning applications which are unable to provide 10% biodiversity net gain as part of a development.

For more information please contact Sejal Patel