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Biodiversity Net Gain – more than just a number

Posted by: , Posted on: - Categories: Biodiversity

It has been great to see the growing amount of coverage in the news about Biodiversity Net Gain (BNG), including a recent episode of BBC Countryfile. Under the Government’s flagship Environment Bill, both Town and Country Planning Act (TCPA) and Nationally Significant Infrastructure Project (NSIP) developments will need to deliver a minimum 10 per cent BNG.

This is a significant opportunity to ensure that developments provide lasting benefits for wildlife and to people’s ability to experience nature where they live and work. For generations, the natural environment has all too often been negatively impacted by development. While designated sites have received certain protections under current law, other habitats have shrunk, connectivity between them has been lost and our ability to experience and encounter wildlife in our daily lives has been reduced. BNG provides a unique opportunity to begin to redress that, to support the nature recovery network and put nature back at the heart of planning and development.

Much of the recent coverage of BNG has focussed, for understandable reasons, on the recently launched Biodiversity Metric 3.  This Metric is a key part of BNG, and it is important that we, as Natural England, get it right. We will continue to listen to feedback and adjust it if  necessary, before we recommend its usage for mandatory BNG, as set out in the Environment Bill, to Government. Any changes will be clearly communicated.

The metric, however, is but one part of BNG. Of even greater importance is ensuring that BNG is undertaken to a high standard and that habitats are created or enhanced to achieve BNG are managed, maintained, and monitored for the long-term.

We were delighted to see the publication in August of the new British Standard for BNG – BS 8683. Developed collaboratively with a wide range of expert input, this is a process standard for designing and implementing BNG. Natural England was involved in the development of this standard which is equally as relevant to land managers delivering off-site net gains as it is to development projects delivering BNG within their development. Uniquely, and unlike the BNG requirement set out in the Environment Bill, the standard can be applied by projects across the UK, not just England.

Natural England is also developing a net gain sites register, a key component of the future mandatory BNG requirement. The register will include information about any site that is being used to deliver BNG. The register will be publicly accessible and detail the baseline biodiversity value of the delivery site and the expected future biodiversity value of that site. The register will also contain information about who owns the site and it will enable such sites to be traced back to the individual development whose BNG requirement they are helping to fulfil. The register will play a key role in minimising the risk of ‘gaming’ the BNG system by ensuring that the same parcel of land cannot be claimed as the means for delivering BNG by multiple developments. It will also ensure that there is a transparent, public record setting out what existed on the site before its use to deliver BNG and what the site biodiversity outcome the site is supposed to deliver. This will help reduce the risk of fraudulent or misleading claims.

However, we recognise that a register alone is not enough. We are finding that people are generally supportive of the principles of BNG but like us, want to be assured that the policy is helping to contribute towards nature recovery (and into local nature recovery strategies) and is providing more opportunities to experience wildlife close to where people live and work.  This is a new policy with new delivery tools relying on a wide cohort of deliverers which brings a lot of uncertainty at this stage that many are picking up on. Natural England, working with Government, has commissioned a study to help shape what a future monitoring and evaluation framework for BNG should consist of and how we can ensure approaches are adapted as we gather more evidence over the long term. Between now and the commencement of the mandatory BNG requirement we will be working with colleagues across Government to implement this macro-level monitoring and evaluation framework.

At the individual site level, we are also starting work on a net gain habitat management plan and reporting template. It is vitally important that habitats are managed and maintained for the duration of the BNG agreement and that, if necessary, corrective measures are implemented if the BNG outcomes forecast through the metric are not forthcoming. None of us wants to see an outcome that looks good in the metrics calculation but then fails to materialise on the ground. Habitat enhanced or created to achieve BNG must achieve the distinctiveness and condition forecast and be managed and maintained over the long-term to benefit wildlife. Currently many habitat plans only consider what is needed over a 5-10-year period. BNG requires habitats be secured for at least 30 years, which means they must be managed and monitored. Adaptive management techniques may be needed to help facilitate this combined with periodic reporting of the habitat outcomes that enable corrective or enforcement (in extremis) action to be undertaken. Natural England will work with key stakeholders to develop a long-term habitat management and reporting plan for use in BNG.

The above only touches on some of the additional detail that is still needed to ensure that BNG delivers the outcome that we all want. This Autumn, Defra will be consulting on BNG Secondary Legislation and Regulations. We anticipate that this consultation will set out more of the detail needed to help ensure BNG delivers for nature and for people. Natural England has been working closely with Defra group colleagues in on this and we encourage everyone to get involved when the consultation is published.

So, to conclude. BNG is not just about the metric, important as that is. It is also about ensuring that BNG is delivered to a good standard, in the right places and in a manner that is transparent and can be managed, monitored, and maintained for the long term.  Natural England has a key role in some aspects and welcomes engagement, but we must all work together over the coming years while this beds in to ensure that we do realise our ambitions – this is too good an opportunity to miss.

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  1. Comment by Professor David Rogers posted on

    Document BS8683 is £218 to the general public and half-price for BSI members. If DEFRA/NE is serious about the application of these new environmental standards BS8683 should be free to members of the public to download.
    I appreciate that this is not the usual BSI funding 'model' but neither does BSI say much, often, about the environment. NE should strike a deal with BSI over the free distribution of this important document.

    • Replies to Professor David Rogers>

      Comment by nickmann posted on

      Thank you for the feedback and suggestion. We did discuss whether the BS8683 document could be free to enable wider take-up and use, but the fees are set by the British Standards Institution. We will re-visit to see if there is something more we can do with BSI here. More generally, Natural England and government are developing further public guidance ahead of the introduction of mandatory BNG, and as part of this we will be seeking opportunities to work with other organisations on their own guidance.

  2. Comment by Professor Ian Rotherham posted on

    A big problem is the idea that catastrophic losses can be offset - which often they cannot. Whilst there are great opportunities to get developers and business to reinvest in biodiversity this should not be an excuse for irreparable damage. Landscape heritage is also not replaceable or capable of being 'offset' - so ancient woods, ancient hedges, veteran trees, traditional unimproved grasslands etc cannot be compensated for. The other real worry with this is the incentive for consultants to offer (for a good-sized fee) offset solutions which are essentially pie-in-the-sky and incapable of realistic delivery and not transparent in terms of their long-term outcomes. This appeals to developers, to politicians, and to planning inspectors since it justifies damaging developments but with a clear conscience - greenwash. We need to engage business and others in genuine commitment to sustainable ecological and heritage solutions. Finally, losses at a particular locale cannot be genuinely offset by actions displaced to another site - ecological systems & local communities simply do not operate in that way. We require more genuinely visionary and pragmatic solutions.

    • Replies to Professor Ian Rotherham>

      Comment by Max Heaver posted on

      Thanks for your comment. This blog doesn’t set out all the detail of the biodiversity net gain proposals, which stress the importance of the mitigation hierarchy in applying net gain in practice and recognise the incompatibility of a BNG requirement with losses of irreplaceable habitats.

      Hopefully some of the links below provide some reassurance, and the forthcoming consultation will give more detail. We think, in combination with local nature recovery strategies and wider policy proposals, that biodiversity net gain will set the stage for visionary environmental improvements but would always welcome more ideas and suggestions directly to the mailbox on the metric 3.0 webpage or through the consultation.

      “Net gain will not weaken existing planning policy protection for irreplaceable habitats such as ancient woodland.”

      “Consultation responses expressed strong support for the proposal that mandatory net gain should not weaken the existing legal and policy protections for protected sites, protected species or irreplaceable habitat. Government will therefore keep irreplaceable habitat sites out of scope of the net gain requirement…”

      “Biodiversity net gain tools and guidance will reinforce and support adherence to the mitigation hierarchy which is already well established in planning policy. Government will improve environmental mapping so that biodiversity impacts can be better avoided in the first instance. We also received support for our proposed approach to introducing a “spatial hierarchy” to incentivise on site and local compensation where appropriate.”

      “A net gain in biodiversity cannot be achieved on areas of development which result in the loss of irreplaceable habitat, such as ancient woodland. In recognition of this paragraph 18 allows the Secretary of State to make regulations that modify or exclude the application of the general condition to irreplaceable habitat. Existing strong planning policy protections for irreplaceable habitat will remain, and will not be replaced or in any way undermined by the biodiversity gain requirement or any regulations to be made in relation to irreplaceable habitat. Sub-paragraph (2) specifies that, where development does impact irreplaceable habitats, regulations must require measures to be taken to minimise the negative impacts of this development on those habitats, and that those measures should be agreed with the planning authority where they are not made by the planning authority in the first place.”
      Para 1659 of the Environment Bill’s explanatory notes:

    • Replies to Professor Ian Rotherham>

      Comment by Nicholas White posted on

      It is important to emphasise that Biodiversity Net Gain does not change or replace any existing protections for irreplaceable habitats.

      Biodiversity offsets also have to be managed, monitored and maintained for at least 30 years with the details set out in a public register.

    • Replies to Professor Ian Rotherham>

      Comment by Mary Parker posted on

      I agree. Worst of all is being able to pay DEFRA for BNG credits. So they can destroy our beautiful Sussex countryside and plant a few trees in Scotland

  3. Comment by Peter Blem for Thanet Biodiversity posted on

    Both Professor David Rogers and Professor Ian Rotherham’s comments above, deserve an urgent response.

  4. Comment by Rebecca Moberly posted on

    Thanks for this excellent blog - really helpful in explaining the context in which the Biodiversity Metric sits and the work going on to help ensure it delivers on its promises.

  5. Comment by Claire Baker posted on

    I agree with Professor Ian Rotherham above and also add the following:

    From my limited exposure to BNG as a resident at Owlthorpe Fields, BNG has been, and I believe will continue to be, used by developers as an excuse to build on more green spaces and habitats.

    The metric does not seem to properly account for the importance of adjacent interconnected habitats or value the habitat itself properly. The developer at Owlthorpe made little attempt to use the mitigation hierarchy and didn’t even complete a full suite of surveys, yet the Government Inspector still granted Planning Permission at the appeal.

    No on-site gain could be achieved, so a payment of £230K has been made to use on an adjacent Local Wildlife Site that is already being managed under an environmental higher level stewardship scheme as a grassland habitat. Double counting at its best! The developer didn’t recognise the adjacent woodland was ancient (it is now registered as such following an incredible amount of work by residents and the help of Nat England) and suggested some inappropriate measures to 'improve' it. I do however support the use of a register.

    What happens in the interim while we wait for any ‘replacement’ habitat and measures to reach the same maturity as the one being destroyed? At Owlthorpe it took decades for the rewilded habitat to form, but the displaced wildlife must now wait a few decades for their ‘replacement’. What is that wildlife supposed to do in the meantime?

    Also, how can an off-site replacement actually be a replacement? The ‘replacement’ will alter another habitat (again using Owlthorpe as an example) and we don’t have an unlimited amount of ‘replacements’.

    Just my own opinion, but I can only see BNG being used effectively in a limited number of cases where some brownfield sites could be improved with on-site measures.

    Additionally, to ensure there is no deliberate obfuscation, developer wildlife surveys should be completed by independently allocated and managed ecologists controlled by CIEEM (or other independent organisation?) but paid for by developers.

    • Replies to Claire Baker>

      Comment by Max Heaver posted on

      Thanks for the comment and sharing your experience. The proposals for mandatory biodiversity net gain and the systems that support it are planned for introduction in 2023, and are intended to improve the elements of practice that we hear concerns about. As the replies above suggest, BNG doesn’t replace wider nature and sustainability provisions in planning policy which have important roles to play through site selection/allocation and raising a host of other planning considerations; what BNG will do is makes sure that any losses are more transparently presented for consideration than they are in current practice and that proper efforts are made to avoid impacts and compensate where necessary. We’re paying close attention to real world examples like this as we continue to design the secondary legislation, policy and mechanisms (like the off-site gains register) that will be in place when the Environment Bill’s BNG requirement takes effect.

  6. Comment by Dr Nicky Rivers, MCIEEM posted on

    Thank you for the article. Are you able please to provide a date when the secondary legislation may be out - rather than just autumn? Many thanks

  7. Comment by Dr Rosalind Sharpe posted on

    This is a very useful blog, and I appreciate the stated openness to input and readiness to adapt the plan as problems emerge, as they inevitably do with new policies. The Food Research Collaboration, in a blog here points out a hard-to-resolve hazard. This is that the policy potentially rewards farmers and land-owners whose land is in poor condition, and thus offers high possibilities for biodiversity gain and can be offered as an off-site BNG credit, whereas landowners whose land is already in a highly biodiverse state can not participate in the scheme.

  8. Comment by Andrew May posted on

    How do you evidence-based biodiversity net gain?

  9. Comment by Peter Massini posted on

    A couple of quick points of clarification if I may. Will the sites register include sites which have opted for an on-site BNG solution or just to sites which are being used for off-site solutions? Will it be LPAs or Natural England that will be undertaking verification checks to ensure that management is meeting stated objectives, and who will be ensuring corrective management is in place and/or taking enforcement action if necessary? Thanks.

    • Replies to Peter Massini>

      Comment by Nicholas White posted on

      Thanks for your query Peter. It is our ambition that the net gain sites register will include both the onsite as well as those offsite locations used for BNG delivery. However, the final details of the register are still to be confirmed with Government and this question (of including onsite) forms part of that discussion.

      It will be for the LPA to satisfy itself as part of the consenting process that the location and proposed management of the BNG outcome is appropriate and, beyond this, that the proposed net gain outcomes have subsequently been delivered. The net gain register will provide a publicly accessible record of the BNG commitments that have been entered into, including the baseline site value and the proposed net gain outcome that is to be delivered.

      Government is developing a biodiversity net gain plan template, which all developments will be required to complete and submit along with their metric calculations to support LPAs with this. This will include a standardised habitat management and reporting plan template. It is anticipated that more details about the above will be set out by Government when they undertake their forthcoming consultation on Biodiversity Net Gain secondary legislation and regulations.

      • Replies to Nicholas White>

        Comment by Peter Massini posted on

        Thanks Nick.

  10. Comment by Julie Alexander posted on

    I think Claire Baker made a good point about the length of time for habitat to mature, and what happens in the interim. Whilst there is a temporal element in the metric, the reality may not be satisfactory. I also think that Dr Rosalind Sharpe's comments in terms of 'reward' are very relevant - this is a matter that comes up in planning in connection with other issues.

    A key concern relates to the expertise and capacity of the LPA to monitor and enforce all aspects of BNG. Many authorities do not have ecologists, and Planning enforcement activities have been reduced by some Councils in response to squeezed resources - planning enforcement is not mandatory. If I am correct in understanding how the system is to be operated , It will be down to the LPA to decide whether it is expedient to pursue action if a site fails to deliver anticipated gains, in the same way as it considers any other planning breach. In these cases resources and Council priorities will be very relevant. There was some suggestion previously that additional financial resources would be made available to help Councils implement the new regime, but there has been little more about this.