The Scottish Government commissioned NatureScot to develop a ‘biodiversity metric’ for Scotland’s planning system.  This is specifically to support delivery of National Planning Framework 4 (NPF4) Policy 3b, which states that national and major developments (or those subject to Environmental Impact Assessment EIA), will only be supported where it can be shown that they will conserve, restore and enhance biodiversity, including nature networks. The policy requires that such proposals demonstrate significant biodiversity enhancement, in addition to any proposed mitigation. A ‘biodiversity metric’ would provide a consistent method of measuring such proposed change.

A Scottish biodiversity metric webpage, providing an outline of this work, has recently been published on the NatureScot website. There will be a focus on adapting the existing English statutory biodiversity metric to produce a tool that is suitable for use in Scotland. Further updates and early signalling of the intended approach will be published on the webpage as the metric project progresses. There will be opportunities to contribute. 

BNG - Biodiversity Net Gain legislation in England

In England legislation requires that most planning permissions (with some exemptions) deliver at least 10% BNG (Biodiversity Net Gain). This can be delivered either on-site or off-site. All off-site and significant on-site habitats should be secured for at least 30 years.

To support this, a statutory biodiversity metric and a statutory biodiversity metric calculation tool have been developed.  Together they measure the biodiversity value of habitats, actual and proposed, by calculating the number of ‘biodiversity units’.
They take into account:

• different types of habitat (grassland, hedgerows, lakes, woodland, watercourses)
• a range of site factors (size, condition, strategic significance, type)
• and factors around proposed newly created or enhanced habitats (difficulty in creation or enhancement, timescale, distance from habitat loss) in different location

The approach in Scotland

NPF4 Policy 3b does not require a specific assessment approach to be used to demonstrate the delivery of positive effects on biodiversity. A range of approaches are currently being used, including England’s metric described above. Lack of consistency and the need to use a metric reflecting Scotland’s policy-led approach (in contrast to England’s legislative approach) will be addressed in the work currently being progressed by NatureScot.

So far

• A summary of key issues from stakeholder consultation during April and May 2024 has been published
• A meeting summary note of the roundtable discussion on the development of a Scottish biodiversity metric which took place in May 2024 is published

Next Steps

The final outputs will include a Scottish biodiversity metric tool for use in the planning system and accompanying guidance (together with any additional supporting information). 

Updates in Scotland

BNG in England

Statutory biodiversity metric in England