Biodiversity Net Gain, guidance for developers and ecological consultants

The Town and Country Planning Act has been amended to make every grant of planning permission deemed to have been granted subject to the following planning condition:

The development may not be begun unless:

• a biodiversity gain plan has been submitted to the planning authority, and 
• the planning authority has approved the plan.

The purpose of the condition is to secure the biodiversity objective, which is that the biodiversity value attributable to the development exceeds the pre-development biodiversity value of the onsite habitat by at least 10%. 

There are different options which can be utilised and combined to achieve net gain. They must be considered in the following order, known as the biodiversity gain hierarchy. 

1. habitat creation or enhancement onsite (within the red line boundary of a development site)

2. making off-site biodiversity gains on their own land outside the development site or buying biodiversity units from a habitat bank

3. or as a last resort buy statutory credits

Although final details may only be required through the discharge of the pre-commencement Biodiversity Gain Plan condition, BNG is often a material consideration when determining applications and Paragraph: 002 Reference ID: 74-002-20240214 of Planning Practice Guidance on Biodiversity Net Gain (GOV.UK: Biodiversity net gain (opens new window)) makes it clear that the Local Planning Authority (LPA) needs to understand how the BNG requirement is to be met prior to determining the application, so that necessary planning conditions can be imposed and/or S.106 Agreements signed. Accordingly, sufficient information is still required at the application stage.