Biodiversity net gain

All planning projects subject to BNG requirements should consider BNG from the very outset, prior to site design, and ideally at site selection stage to help minimise the need for providing replacement habitats.

Mitigation hierarchy

Gains in biodiversity should be achieved on-site (within the proposed development site) and this should be a key consideration when designing development proposals.

This falls in line with the principle of the mitigation hierarchy that is embedded in national planning policy, where the impact on biodiversity must first be:

• avoided, then
• minimised, then
• compensated for on-site

Only as a last resort, and if compensating for losses on-site is not possible, then biodiversity losses should be offset by gains off-site.

Compensating for biodiversity losses elsewhere

Where a development is set to lose biodiversity value because of proposed work, conservation work can be done on the site to try and compensate for the losses. This is as well as any planned measures to avoid or mitigate biodiversity loss.

Compensating for the biodiversity loss by improving biodiversity elsewhere should be used as a last resort. In certain cases, it is not appropriate and should not be used.

Developments must:

• have applied the mitigation hierarchy
• follow national government BNG principles and rules including being as local to the site of impact as possible

The habitat should also be located somewhere of strategic significance to ecology, for example where they help wildlife to move through the landscape by providing a connective corridor or buffering an existing wildlife site.