Bath and Northeast Somerset Council and the introduction of Biodiversity Net Gain requirements

Bath and Northeast Somerset Council have introduced Biodiversity Net Gain (BNG) requirements ahead of its mandatory introduction in November 2023. Please note - Councils developing BNG approaches in advance of its mandatory introduction may have to adapt their approaches to comply with the details of legal requirements in November 2023.


Bath and Northeast Somerset Council shared how they introduced Biodiversity Net Gain (BNG) requirements

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Bath and Northeast Somerset Council began thinking about the implementation of measured Biodiversity Net Gain (BNG) in early 2018 after the publication of the Government’s 25 Year Environment Plan.

The year after the 25 Year Environment Plan was published, the Council declared a Climate Emergency and developed a Climate Action Plan in late 2019. This identified the main sources of green-house gas emissions within the area and priority areas for action. In the following year, the Council declared an Ecological Emergency which recognised the essential role played by nature in society and set out the council’s intent to do more to protect wildlife, and enable nature’s recovery..  

Just prior to this in in May 2020 a role of ‘Biodiversity Champion’ was identified for an elected member in the council, to advocate for decision-making within the council to be guided by its impacts on the biodiversity and the natural environment. This role is highly valued by council officers.

The Council’s Corporate Strategy, adopted in 2020, firmly emphasised a timeline until 2030 to prioritise two core visions:

  • Tackling the climate and nature emergency
  • Giving people a bigger say

It was the drive of support from its members, the subsequent emphasis on the environment within the Corporate Strategy, and the declaration of an Ecological Emergency which led to Bath and North East Somerset Council to develop and implement a BNG policy ahead of mandatory implementation in November 2023.


Timeline of Bath's BNG Journey

The project

Policy development

Bath and Northeast Somerset Council developed the interim BNG planning policy as part of a partial update to their Local Plan which has now been fully adopted (January 2023). The proposed policy approach, which was first published for public consultation in Spring 2021 contained three options for the implementation of BNG:

  1. ‘Development will only be permitted where a Biodiversity Net Gain of at least 10% is demonstrated and secured in perpetuity (at least 30 years) subject to other requirements as set out below’
  2. ‘Development will only be permitted where a Biodiversity Net Gain of 15% is demonstrated and secured in perpetuity (at least 30 years) subject to other requirements as set out below’
  3. ‘Subject to government guidance consider bespoke local Biodiversity Net Gain requirements for brownfield sites and householder applications’

Following the consultation Bath and Northeast Somerset Council took the decision to implement option 1 and require 10% net gain for all major developments and no- net loss with appropriate net gain for minor developments. The policy is now adopted and to date 84 BNG applicable planning applications (excluding change of use applications) have been submitted.

To support the new BNG policy requirements, the council updated their planning obligations supplementary planning document (SPD) and have prepared a BNG guidance note. This will be developed as a BNG SPD once all  Environment Act secondary legislation is in place. Critically the council also undertook some restructuring and recruiting.

Restructuring and recruitment of an environment team

Several new posts have been created including a Nature Recovery Manager to work on the Local Nature Recovery Strategy which Bath and Northeast Somerset Council will be leading on (on behalf of the West of England Combined Authority), a Green Infrastructure Programmes Manager and a Biodiversity Net Gain officer. The decision to create a new team was specifically chosen to separate environment to planning and

Council-wide practice

Bath and North-East Somerset Council recognise the need for better information, training and collaboration around BNG across the council, and the GI and Nature Recovery Team run internal training programmes for different audiences. To date this has included training for members, planning validation teams and planning officers, as well as senior managers across the Sustainable Communities Directorate. This has covered the background to BNG, the policy and laws surrounding it, why it is being implemented and the opportunities and risks for different service areas.

To continue to emphasise integration and collaboration on the implementation of BNG, the Green Transformation Service is considering how collaboration with the Council’s IT services could be used to streamline BNG data and make it more available and easier for council officers and members of the public to view. It is anticipated that the council will develop and manage a digital BNG  register  to capture both on-site and off-site BNG secured within district..

Challenges and solutions

Justifying funding prior to mandatory BNG

Unlocking funding prior to new burdens funding allocation (especially given the lack of clarity on the timing and level of financial support) for BNG was challenging but essential considering the council’s Ecological Emergency Declaration and the pending mandatory BNG requirements. Unusually and happily, stars were aligned in terms of the corporate strategy, member support, a new service director and creative team leaders.

The restructuring has been fundamental in giving the team the capacity to research, consider and prepare for BNG delivery within Bath and Northeast Somerset.  The Green Infrastructure & Nature Recovery Team now has 1.4 full-time equivalent staff solely working on the preparation for BNG, including developing the role of council land in BNG off-set provision. In the longer term the roles will focus on the monitoring and wider benefits and opportunities of BNG off-sets for nature recovery.

BNG as a cross-department issue

The Council’s new GI and Nature Recovery team felt that the introduction of BNG, whilst long announced, wasn’t recognised as a cross-service issue as it should be, but instead was viewed primarily as a planning service issue or problem. The team felt it should be better viewed as a cross-service issue and opportunity for better place making, supporting access to nature, for improving health and well being, for supporting the local green economy, as well as benefiting biodiversity. The beneficial outcomes from BNG were therefore seen as significant prizes from investing early in a BNG process.

To promote and improve engagement across different services, the  Green Infrastructure & Nature Recovery Team engage and network both internally within the council to provide increased support and awareness for BNG, and also with  neighbouring councils and with different partnerships such as the West of England Nature Partnership, to share and develop good practice. They also contribute to the council’s Developers’ Forum to support planning agents and developers.

Advice to other local authorities

Collaboration and learning

Bath and Northeast Somerset Council emphasise the importance of learning and engaging with other councils, as well as other services areas beyond planning. Their early introduction of BNG as an interim policy provided an opportunity to learn from the experience prior to its mandatory introduction and they are happy to share their experiences with others.

The importance to share information about BNG and to collaborate within the council and across different service areas beyond planning is stressed. Both the opportunities and risks need to be shared, with emphasis of what can be gained from early collaboration on council GI projects, council developments, land management and community initiatives. The experience to date has been really positive and is helping to fast track and enable much more collaborative working across the council for nature recovery. This could be key if the development of BNG practice falls to single officers.

They also stress the importance of the Planning Advisory Service’s BNG Practitioner Network which hosts a shared online space for local authority officers to share their experiences and hosts regular deep dive sessions in preparation for mandatory BNG.

Emphasise pro-active funding opportunities

Bath and Northeast Somerset Council highlight that a small amount of up-front investment to prepare for BNG can deliver significant benefits. They recommend emphasising the need for funding and resources ahead of implementation to promote a pro-active preparation period and avoid a reactive response to mandatory BNG