Biodiversity Net Gain Consulting

What is the Biodiversity Net Gain Requirement

Since February 2024 it has been mandatory for certain development projects in England to deliver at least 10% biodiversity net gain. This is a way of ensuring that wildlife habitats are left in a better state after development than they were before development. It is part of the wider strategy to reverse biodiversity decline in the UK.

Whilst the process can be challenging, biodiversity net gain can help to deliver meaningful biodiversity enhancements in a way that is complementary to much-needed development projects. Biodiversity net gain is about habitats – the fundamental building blocks of our beautiful countryside that support the plants, animals and natural processes we need for a healthy planet.

Understanding your obligations can be complicated – this is a relatively new area and things are still changing. We have provided some guidance, but if in doubt please do not hesitate to contact us and we will be happy to help.

Which Developments are Exempt from Biodiversity Net Gain

Most ‘typical’ developments – such as housing and renewable energy projects – are included in this requirement, and it even covers smaller projects. Some planning applications are exempt from biodiversity net gain.

The main exemptions are:

• Planning applications submitted before 12th February 2024
• Householder applications
• Self-build and custom-build applications
• Applications below the threshold, meeting the biodiversity net gain de-minimis criteria

Finding out whether your project is included or whether it might be exempt from the biodiversity net gain requirements can be complex – speak to one of our team if you would like help with this.

How is Biodiversity Net Gain Measured

Biodiversity net gain is measured using a nationally standardised metric, which helps us to put a number on the amount and quality of habitat on a site and compare this with the proposed habitats. The results are presented as a change in the number of ‘Habitat Units’ before and after development, expressed as a percentage net gain. The calculations have to be provided for all ‘area habitats’ – grassland, woodland etc, linear habitats such as hedgerows; and watercourses.

Special qualifications are needed to survey some habitats for biodiversity net gain – we only use River Condition Assessment qualified surveyors for our watercourse surveys. Our long and varied experience of habitat surveys across the UK and overseas also underpins the quality of our habitat surveys.

Ultimately the net gain metric, spreadsheet and percentage changes are just a way of representing the complex and sometimes unpredictable natural world. The government guidance on biodiversity net gain is clear that the “biodiversity metric is not a complex or comprehensive ecological model and is not a substitute for expert ecological advice.” Common sense, experience and a collaborative approach are all essential ingredients in ensuring that biodiversity net gain calculations best present your project and its potential.

Off-site Biodiversity Net Gain

One of the key principles of biodiversity net gain is that habitat creation and enhancement should, where practical and reasonable, be local to any impact. Generally, it is expected that the 10% net gain requirement is delivered on-site i.e. within the red line planning application boundary. This is not always possible and may not always be the best way to deliver meaningful biodiversity enhancements. It is possible to deliver a project’s net gain requirement ‘off-site’, either within the land owned by the applicant (blue-line land) or by purchasing ‘biodiversity units’. The number and distribution of sites on the net gain register that can sell biodiversity units is growing, and where a site is not available for your development the ‘fall-back’ position is the purchase of statutory credits from the government.

The cost of buying net gain credits can be substantial, so by ensuring that everything has been done to maximise on-site gains we will help you to manage these costs.

After consent: 30 years of monitoring

Securing planning permission is only the start of a BNG project. Under the Environment Act 2021, the new and enhanced habitats on the site must be managed and monitored for at least 30 years, with formal reports back to the Local Planning Authority at years 2, 5, 10, 15, 20, 25 and 30. That long-term obligation is set out in a Habitat Management & Monitoring Plan (HMMP), and it sits with the developer or landowner for the full thirty years.

Bengrove provides the monitoring service that discharges the obligation – drone-based condition assessment, botanical surveys, formal reporting and LPA liaison. Where we have written the metric and the HMMP, we are uniquely positioned to deliver the monitoring that follows. Read more about our BNG Monitoring service.