Biodiversity net gain (BNG) is a way of creating and improving natural habitats. BNG makes sure development has a measurably positive impact (‘net gain’) on biodiversity, compared to what was there before development. 

• For an overview of key information and terms relating to BNG, read Understanding biodiversity net gain GOV.UK
• Planners, developers, land owners and those already involved with BNG can view the statutory guidance relating to BNG on GOV.UK

Under the statutory framework for biodiversity net gain, subject to some exceptions, every grant of planning permission is deemed to have been granted subject to the condition that the biodiversity gain objective is met ('the biodiversity gain condition'). This objective is for development to deliver at least a 10% increase in biodiversity value relative to the pre-development biodiversity value of the onsite habitat. This increase can be achieved through onsite biodiversity gains, registered offsite biodiversity gains or statutory biodiversity credits.

Information required to support a planning application

Exempt applications must include a supporting statement setting out which of the exemption criteria are met and evidencing that exemption. Photographs of the site or site plans with measurements may be required as supporting evidence.

Applications which are not exempt will need to demonstrate that they have followed the biodiversity hierarchy and achieved the necessary minimum 10% gain by including the following documentation with their application:

• A completed statutory metric or small-sites metric where applicable.
• A clear detailed plan of current on-site habitats.
• A supporting BNG report which describes the current biodiversity value 

View the statutory biodiversity metric tools and guides and associated guidance on GOV.UK

A standard condition will be applied to all relevant planning decisions under The Environment Act 2021 and is set out in Part 2, Regulation 13. The condition states that development may not be started unless:

• A biodiversity gain plan has been submitted to the planning authority, and
• The planning authority has approved the plan.

The council may choose to include additional conditions on the decision notice around securing elements of site design, landscaping etc. and may secure elements of BNG through a Section 106 agreement.

The biodiversity gain plan

The biodiversity gain plan is a document which sets out how a development will deliver biodiversity net gain and allows us, as the planning authority, to check whether the proposals meet the biodiversity gain objective. Applicants must complete the biodiversity gain plan template available here biodiversity gain plan on GOV.UK.

The applicant must also submit:

• A completed statutory metric or small-sites metric where applicable, even if submitted at planning application stage.
• Pre-development and post-development habitat plans.
• Any registered off-site biodiversity gain allocated to the development.
• Any biodiversity credits purchased for the development.
• If necessary, a Habitat Management and Monitoring Plan (HMMP) using the Natural England template available here Habitat Management and Monitoring Plan Template - JP058.

Biodiversity net gain and the Local Nature Recovery Strategy

Local nature recovery strategies (LNRS) cover the whole of England. Each strategy area will include a local habitat map and a written statement of biodiversity priorities. A habitat unit is a proxy measure for an area of land. Habitat units are used by the statutory metric tool when calculating biodiversity. If you deliver biodiversity units in a strategic area which has been identified in the LNRS, the biodiversity metric tool will attribute those units additional value.

View further information on our Local Nature Recovery Strategy page.

Biodiversity net gain (BNG) and private residential gardens

For development proposals subject to the mandatory biodiversity net gain (BNG) requirements under the Environment Act 2021, applicants may include both vegetated and non-vegetated areas of private residential gardens (residential curtilage) within the statutory biodiversity metric supporting a planning application.

Natural England has advised the Council that land within residential curtilage may contribute towards achieving the mandatory 10% BNG requirement, provided that the statutory biodiversity metric rules and guidance are followed.

Council approach

Herefordshire Council recognises that private residential gardens can form part of a BNG strategy:

• Minor development proposals may reasonably rely on gardens to deliver all or a significant proportion of the 10% BNG requirement.
• For major or larger-scale developments, where a substantial proportion of the biodiversity net gain is proposed within private residential curtilage, the council will normally:
• Seek a balanced approach, and
• Request that a proportion of BNG is delivered outside private gardens.

This approach reflects the following considerations:

• Habitat within private gardens is less certain to be retained and managed over the long term and is generally not secured in the same way as other habitats.
• The statutory biodiversity metric allows for garden habitats but assigns them low biodiversity value.

We will apply a case-by-case approach, taking into account:

• The scale and type of development.
• The proportion of BNG delivered within residential curtilage.
• The overall quality, security, and strategic value of the proposed habitats.

Where proposals other than minor developments rely heavily on private gardens to meet the BNG requirement, applicants should expect this to be subject to scrutiny and potential negotiation to ensure an appropriate and policy-compliant outcome.