Biodiversity net gain - what does it mean?

Some developers and government agencies already follow a biodiversity net gain approach in response to the current National Planning Policy Framework (NPPF), but the new Bill will make such approaches a statutory requirement.

What does this mean for developers?

It requires developers to measure the value of habitats on site before a project is built and achieve a higher value of habitat after its completion – this applies to all types of development.

• Developers need to prepare and submit plans to show how they are meeting the requirements.
• Greater weighting applied to biodiversity at planning stage.
• Introduces commercial risk when not considered at an early stage – for example through:
  • Potential impact on developable area and future income through creation of larger habitats.
  • Potentially significant financial costs if requirements cannot be met on site, e.g.. purchase of additional land, or
• Increased maintenance costs.

Note: current species protection would still apply and so would not alter approaches to mitigation and licensing requirements.

How is biodiversity net gain assessed?

The current standard for assessment is DEFRA’s V1 metric (V2 is under consultation). Using the metric, an audit of habitats is undertaken during a field survey (it can be done using data from Preliminary Ecological Appraisals; specifically, Phase 1 habitat survey results).

Larger areas of higher quality habitats receive higher values, requiring more effort on the part of the developer to replace and achieve a net gain for biodiversity. Thus, there are incentives to avoid important habitats in favor of sites which are not important for biodiversity; for example, achieving a net gain following the removal of woodland would be more difficult than ornamental planning.

How will net gain be delivered in practice and what are the challenges?

• The NPPF mandates net gain through the planning system, and many Local Planning Authorities have adopted the principal already.  
• Biodiversity loss is a sensitive topic in the public arena.
• Habitat creation on-site is the primary way of achieving net gain, replacing low quality habitats lost to development with smaller but higher quality ones.
• Offsetting approaches could be considered, where cash is paid into habitat creation/restoration funds through S106 or CIL – such schemes are in their infancy at present and on-site integrated solutions likely to be favoured.

Councils and other decisions makers are adapting to this change, which is dragging ecological elements of the planning system into a more quantitative world. It’s easier to demonstrate to a client and engineering team the value of creating woodland, for example, if you can quantify its loss.

How can Delta-Simons help?

• Sustainable master planning – support early to identify constraints and opportunities using GIS.
• Provision of Biodiversity Net Gain Assessments by undertaking DEFRA Metric studies.
• Development of net gain strategies for developments through provision of habitat creation plans and enhancement programs.
• Working closely with architects and landscape planners to ensure net gain is applied through the project life cycle.
• Consultation, negotiation and management of biodiversity net gain requirements with Local Planning Authorities and Natural England.

For more information contact Charlotte Sanderson-Lewis, Associate Ecologist, Tel: 07884 498315.

See all Ecology services.