What is Biodiversity Net Gain?

Biodiversity Net Gain (BNG) is development that leaves biodiversity in a better state than before. The revised National Planning Policy Framework (2019) states that local planning authorities (LPAs) in England should identify and pursue opportunities for securing measurable net gains for biodiversity. Whilst BNG is not a new concept, the Environment Bill will see the introduction of a mandatory requirement for 10% BNG on most new developments. This is likely to come into effect later this year (the committee examining amendments has been adjourned in light of Covid-19).

Who Does It Apply To?

The mandatory requirement will apply to most developments where planning permission is required. Smaller development sites (with less than ten residential units or an area less than 0.5ha) will be subject to a more simplified requirement. Some LPAs also have their own local policies in place, so local knowledge is essential.

Some businesses have already introduced their own BNG targets ahead of the new legislation being introduced, including within some industries to which the Bill will not apply. This is because the results of delivering BNG are apparent in terms of economic benefits and corporate reputation.

Biodiversity Net Gain Assessment

BNG Assessment involves calculating biodiversity units pre- and post-development, and then calculating the percentage change, using a Biodiversity Metric. The key steps to an assessment are as follows:

  1. Conduct a pre-development field survey to catalogue baseline habitats (EMEC can undertake this as part of the usual Preliminary Ecological Appraisal to make the process more efficient).
  2. Review landscape and planting proposals to assess post-development habitats.
  3. Use a Biodiversity Metric to calculate pre- and post-development biodiversity units and the percentage change. EMEC uses the Natural England Metric 2.0 (2019 Beta Version), but other local versions can also be used.
  4. If there is a shortfall in the target BNG (i.e. less than 10%), EMEC can provide pragmatic recommendations for achieving an increase in post-development biodiversity units. Consideration can be given to on-site and off-site habitat creation and enhancement solutions. EMEC uses local knowledge to secure the best results for local wildlife, maximising the number of biodiversity units that can be achieved.


How Can EMEC Help?

  • EMEC can conduct a BNG Assessment and advise developers how best to achieve their BNG target.
  • EMEC can discuss options for increasing post-development biodiversity units through local off-site habitat creation.
  • EMEC’s land management team can enhance existing habitats and create new habitats with high biodiversity value.
  • EMEC can prepare long-term ecological management and monitoring plans for a site. EMEC’s land management team can deliver on those plans in the long-term and satisfy all long-term management and reporting requirements.
  • EMEC can project manage the entire BNG process through its whole service provision.