Legal Aspects of BNG

The Environment Act, 2021 secures the BNG via a pre-commencement condition, which states:

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 gain plan.

To discharge this condition and commence development the developer must submit a Biodiversity Gain Plan to the LPA. At the application stage, the developer is not required to submit a full Gain Plan but must submit a comprehensive baseline survey and biodiversity metric. However, there are benefits to giving as much information as possible on post-development plans and any offsite compensation needed.

The Biodiversity Gain Plan template should be used which is downloadable on the government’s Biodiversity Gain Plan page.

The delivery of any off-site units must be secured legally either with a S106 or a Conservation Covenant, be registered on the National BNG register and be maintained for at least 30 years. Before the Gian Plan can be approved the offsite unit must be allocated to the development.

On-site unit gain may be secured with planning conditions or S106.  These are subject to a habitat management and monitoring plan for 30 years and developers are responsible for monitoring the habitat and reporting to the LPA. Habitats within residential gardens, and other non-significant gains cannot be legally secured and will not require a management and monitoring plan for the 30 years.

Mitigation Hierarchy

BNG sets a spatial hierarchy of habitat delivery, where the delivery of 10% net gain on site is the priority before off-site options are explored. This is in line with the 2021 National Planning Policy Framework that states any impacts to biodiversity must first be avoided, then minimised and as a last resort compensated for. To ensure that the mitigation hierarchy is adequately applied, developers must consider BNG early in the development planning process and evidence this within their planning application. The steps of the mitigation hierarchy are set out below.

Any off site provision should be provided in proximity to the development and within the Local Authority area. There is also a ‘last resort’ option for developers to purchase credits if on-site and off-site options have been exhausted; this is operated as a National Scheme by Natural England. Developers must submit clear evidence with their planning application to show that all other options have been exhausted before using the national credit scheme.

Monitoring, Enforcement and Reporting

Monitoring of BNG over the 30 years is the responsibility of the developer/land manager on-site, and the landowner/manager of the off-site provision. Details about the frequency of monitoring and maintenance of this should be set out in their Habitat Monitoring and Management Plan (HMMP) and legal agreement. The LPA will be responsible for reviewing monitoring, and reporting on BNG delivery within their jurisdiction, Enforcement responsibilities will depend on the legal agreement used.