Below is a selection of questions on Biodiversity Net Gain (BNG) that members have asked. The answers represent industry best practice. The responses represent industry best practice as we understand it from our engagement with the relevant government departments and SNCOs. We intend to keep adding to this Q&A page as a resource for BNG practitioners. If you have a question that you would like answered, please contact the CIEEM policy team at policy@cieem.net.
Regulation
How do you intend to create a standardised framework for regulating the offsite BNG market beyond the national register? Do you intend to provide criteria for reviewing habitat banks beyond this for use by LPAs or RBs.
Work is being undertaken by the British Standards Institute to develop best practice principles for biodiversity markets.
What is the inheritance tax liability on land in a 30 year BNG agreement?
Independent legal advice should be sought to quantify IHT liability.
How do we stop the abuse of the Self-Build exemption? Many local planning authorities (LPAs) are receiving self-build exemption applications, which upon scrutiny turn out not to be self-build or are changed from self-build after validation. Furthermore, outline planning applications are being received for multiple self-build homes. Is this exemption justified? If so, how do LPAs stop the abuse of this exemption?
An exemption from BNG applies to self and custom build applications when it meets all the following conditions:
- consists of no more than 9 dwellings
- on a site that has an area no larger than 0.5 hectares
- consists exclusively of dwellings that are self-build or custom housebuilding as defined in section 1(A1) of the Self-build and Custom Housebuilding Act 2015
The Self and Custom Housebuilding Act 2015 Section 1 (A1) sets out the definition for self-build and custom housebuilding which means the building or completion by a) individuals, b) associations of individuals, or c) persons working with or for individuals or associations of individuals of houses to be occupied as homes by those individuals. In recognition of some confusion around what qualifies as a self- build, Defra updated the BNG guidance on 21st August 2024 Biodiversity net gain: exempt developments – GOV.UK (www.gov.uk).
When will the exemption for retrospective applications be closed? Is there a stop date for exemptions to retrospective applications? The concern is that if not, this loophole will continue to be used to avoid the requirement for BNG.
BNG does not yet apply to retrospective planning permissions made under section 73A. There are provisions within Schedule 7A of the Town and Country Planning Act 1990 which allow for modifications to the statutory framework in respect of planning permissions granted under section 73A, and regulations would need to be brought forward to apply BNG requirements apply to these circumstances.
Is there any prospect of building flexibility into the BNG rules, such that small gains on small sites could be collected/coordinated, to deliver more strategic and meaningful biodiversity gains nearby? For example, through intervention and enhancement at sites within the LPA area such as Country parks.
Under mandatory BNG, the delivery of off-site biodiversity units needs to be guaranteed before the gain plan is approved. Delivery of these units requires funding and legal security, meaning that contributions can’t be pooled and spent later. An LPA could fund improvements of their country park, register it as a gain site, and then sell the biodiversity net gain units to small developments as needed to recover the costs.
How can the impacts of statutory utilities providers be managed? The statutory powers of utility providers enable them to access and use land in connection with their statutory purposes. This can include land used for habitat banks or land that has been provided to deliver the required BNG in connection with approved developments. There appears to be no obligations on these statutory undertakers to restore or compensate for any losses of biodiversity resulting from their operations. Please can you advise on ways of managing these risks?
The statutory powers of utility providers are within a separate framework which sits largely outside of planning. Habitat banks would need arrangements in place to address situations which result in a detrimental impact on the habitat. This could be covered by clauses within the agreements in place, stipulating what should happen if this type of situation arises, and could also include force majeure clauses.
Biodiversity Metric
If I want to change 100m2 of amenity lawn into a manège (area for horse training) I can’t offset with species rich hedgerows around the perimeter because the metric won’t allow this despite hedgerows clearly offering more biodiversity than an amenity lawn. What should I do?
There are three types of biodiversity units, which are calculated in three separate ‘modules’ of the metric (area units, hedgerow units and watercourse units). The size measurement for these modules varies between area (m2 or ha) and length (m or km).
Biodiversity unit outputs, for each type of unit, must not be summed, traded, or converted between types.
The requirement to deliver at least a 10% net gain applies to each type of unit. This means that the loss of area habitats cannot be compensated for with hedgerow creation.
This rule and the metric trading rules ensure that the habitat provided is appropriate to compensate for the loss.
What should I do with a “lost” river?
User guide currently states: Permanent loss of watercourses – Natural rivers cannot be permanently lost. Permanent loss of a watercourse length only applies to canals or ditches.
In the metric (or user guide), would it be possible to blank out habitat conditions that are not achievable within a 30 year period (e.g. other broadleaved woodland in good condition)?
The removal/blanking out of condition categories for habitats that take 30+ years to reach, could disincentivise the creation/enhancement of habitats with a 30+ year time to target condition.
In specific cases, there may be a need to meet the trading rules for high distinctiveness habitat which would prompt the requirement to enter into a legal agreement to secure a habitat for more than 30 years to reach target condition. For woodland, see page 17 in Metric User Guide (July 2024).
Where a 30+ year option is selected in the metric the applicant should provide evidence to justify why the choice of habitat and condition combination, how it will be achieved over the timeframe. The LPA and habitat manager should ensure the legal agreement covers the commitment for the extended duration.
Will there be a table with the translation from UKHab habitat types to Metric habitat types?
Tab G1 in the Statutory metric provides this information.
Is there any intention to introduce a High distinctiveness neutral grassland to the metric, like there is for acid and calcareous grassland?
Future consultations on the metric will consult on the inclusion of additional habitats.
Support and Guidance
Will additional funding be provided for LPAs, in order that they can deploy adequate resources for review and enforcement of BNG implementation?
LPAs are responsible for monitoring compliance with conditions set. Where planning obligations are used, LPAs can charge a monitoring fee through section 106 planning obligations, to cover the cost of monitoring and reporting on delivery of that section 106 obligation. Monitoring fees can be used to monitor and report on any type of planning obligation, for the lifetime of that obligation. Councils could also seek to recover costs in relation to the preparation of the section 106 agreement.
Where conservation covenants are used, it will be the responsibility of the buyer and the responsible body to make sure, in agreement with the landowner, that adequate arrangements exist to monitor delivery of the gains. An LPA may apply to be a responsible body however there is no obligation on them to fulfil this role.
Is it the intention to provide guidance on the creation of various metric types (for example, to differentiate between the different preparation or planting needed to achieve different woodland types after 30+ years)?
Industry would be best placed to provide these experience-led standards, which are likely to be subject to local variations.
There is currently no mechanism to amend a biodiversity gain plan once it has been approved. If the proposed habitat creation is unsustainable and could be replaced by an equivalent or better alternative (according to the biodiversity metric) could a mechanism be put in place to allow this?
It is assumed the question relates to amending proposals for on-site habitat creation that have been previously agreed with the local planning authority through the approval of the Biodiversity Gain Plan.
In principle, if the development has not commenced, it would be possible to amend this through re-applying to discharge the condition requiring the approval of a Biodiversity Gain Plan, effectively substituting a previously approved gain plan for another (assuming this is approved by the LPA).
Alternatively, should an application be granted to vary a permission under Section 73 of the Town and Country Planning Act 1990, this may trigger the requirement for an updated Biodiversity Gain Plan to be submitted – as set out within Paragraph 016 of the Planning Practice Guidance, if any conditions attached to the new planning permission granted under section 73 do affect the post-development biodiversity value, then a Biodiversity Gain Plan for the new permission must be submitted and approved prior to the commencement of the permission.
It should be noted that a section 73 permission cannot be used to vary or remove the biodiversity gain condition.
In cases where a development has commenced, there is currently no mechanism in place within the statutory framework that would allow for these changes to be made, as BNG requirements are implemented through a pre-commencement condition. There is an expectation that these details are finalised prior to the commencement of development.
If habitat creation works are banked but the units don’t sell for several years, when exactly does the 30 year clock start ticking?
The clock starts once the habitat enhancement works are complete and maintenance under the legal agreements starts, regardless of when the gains are sold/allocated.
Should planning applications for projects to improve the natural environment still be subject to the BNG requirements? Many such projects (including those intended to create BNG credits) trigger the requirement for planning permission e.g. because of the excavation of wetlands. Currently, such projects are being required to demonstrate how the minimum 10% BNG will be delivered. This seems paradoxical when the whole purpose of the project is to deliver benefits for nature.
Biodiversity gain sites are exempt from BNG. Developments undertaken mainly for the purpose of fulfilling the BNG planning condition for another development are exempt. See Biodiversity net gain: exempt developments – GOV.UK (www.gov.uk)
Should planning applications for projects to provide strategic mitigation for development impacts on the natural environment still be subject to the BNG requirements? Similarly, should projects intended to provide mitigation for impacts on the natural environment, such as constructed wetlands to remove nutrients from polluted catchments and new ponds excavated to provide compensation under the District Level Licensing (DLL) scheme for great crested newts, still be required to deliver BNG?
Biodiversity net gain: exempt developments – GOV.UK (www.gov.uk)
Biodiversity gain sites are exempt from BNG. Developments undertaken mainly for the purpose of fulfilling the BNG planning condition for another development are exempt.
Biodiversity net gain – GOV.UK (www.gov.uk) Paragraph: 003 Reference ID: 74-003-20240214
Development of a biodiversity gain site. Development which is undertaken solely or mainly for the purpose of fulfilling, in whole or in part, the biodiversity gain condition which applies in relation to another development.
Will Defra be establishing a regular forum/website for these type of questions as many LPAs would welcome access to speedy and reliable advice on BNG queries?
PAS host Base Camp for LPA questions, where FAQs are also published. Consideration as to how collaboratively best address industry questions and refine guidance is underway.
Will there be support for LPAs in determining when Rule 4 can be applied to deviate from the trading rules? Currently many LPAs are reluctant to deviate even if the criteria for deviating from Rule 4 can be met.
The user guide on pages 17-18 sets out the rules for this and states the ‘LPA needs to be satisfied that the exceptional ecological circumstances in which rule 4 can be applied are occurring’.
NE is not a statutory consultee for BNG but can provide discretionary advice subject to local capacity on a chargeable basis.
It would be really helpful to have some guidance/examples of situations where the LPA can agree exceptional circumstances where the standard BNG approach can be amended. (Rule 4 in the user guide, for which the guidance covers situations where the ecological reality makes it inappropriate because, for example, there is particularly sensitive habitat, but not ones where common sense indicates some element of BNG is not justified. This is not discussing the exemption where BNG is not needed for a scheme at all). Examples that spring to mind are: Relatively small site, for which terrestrial habitat BNG is required, and LPA has asked for red line boundary to include a long access track, even though there will be no physical works on the track, simple vehicles travelling over the track. This case would not increase the terrestrial habitat baseline value, but if for part of its length the track is within 10m of a watercourse, it could be seen as triggering the watercourse 10% BNG requirement, despite complete absence of any development or ancillary works within that 10m buffer. Pipeline where there are long sections with the pipeline whole installed by directional drilling, so tunnelling with no even temporary disruption of surface habitats. LPA should have potential to approve an alternative ‘RLB’ for BNG where habitat that has no intervention whatsoever, not even vehicles tracking over it, is excluded.
Guidance from Making an application – GOV.UK (www.gov.uk) Paragraph: 024 Reference IS: 14-024-20140306 states: ‘The application site should be edged clearly with a red line on the location plan. It should include all land necessary to carry out the proposed development (e.g. land required for access to the site from a public highway, visibility splays, landscaping, car parking and open areas around buildings).” Hence the access road should be included.
If the red line boundary (RLB) falls within the riparian zone of the watercourse then details within the User Guide pages 39-43 should be followed.)