Our first Natural Capital blog highlighted policy and legal changes coming down the track as efforts to understand the services provided by the environment (ecosystem services and accounting) and use them to inform policy. This is allied to investor interest in Environmental and Social Governance (ESG). To be more than a buzzword you have to be able to measure what you treasure. In the Environment Act 2021 world of delivering biodiversity net gains through the Planning regime, the metric matters, not least because it will get tougher over time.
Natural England released a new and improved ‘3.0’ version of its biodiversity metric in July 2021, to increase certainty and provide a benchmark tool for the Environment Act. Metric 3.0 has now had a full six months to flourish, but will it measure up?
Changes from the Beta Version
Metric 3.0 is still a land-based biodiversity calculator to measure the existing baseline value of a site and predicted biodiversity gains and/or losses from development. The overall methodology and inputs are unchanged. The changes are technical tweaks – for example, removing accelerated succession (a complex mechanism for calculating the maturation of woodland habitats) and the connectivity multiplier (which was often open to interpretation).
Metric 3.0 will smooth variations in metric outcomes – many of which will be welcomed:
- The incentive for the advanced creation of habits. Metric 3.0 proportionally reduces the time needed to reach a habitat’s target condition where it has been created or enhanced (and allows habitat difficulty multipliers to be applied once a habitat has been established). The change rewards developers for early biodiversity improvements by offering a higher weighting than if the improvements were done as part of development works. For local planning authorities eager to realise biodiversity improvement, this change in the Metric 3.0 is a significant improvement over its beta version.
- The allowance for delayed creation/ enhancement of habitats. Metric 3.0 now allows for delayed creation/ enhancement of habitats – e.g. where there will be a significant delays due to phased developments and developments which temporarily require parts of the development site for construction purposes.
Metric 3.0 therefore acknowledges that habitats may be created in advance of development or after development has taken place, but incentivises advance creation.
- The ‘small sites’ metric was also released at the same time as the revised metric, which is a simplified version of Metric 3.0 for residential developments on small sites (which were will now fall within the mandatory BNG requirement).
- Like 2.0, there is a balance – while changes have been made to change the valuation of certain habitats, the presence of other variables in the metric’s calculations softens these major amendments.
Arbitrary Rules?
For the critics of 2.0, Metric 3.0 has not done enough to assuage grumblings given it still relies on land (i.e. habitat) to assess and model biodiversity – rather than actual species richness. As result, there will always be oddities:
- 3.0 may end up overcompensating in trying to reduce the attractiveness of, for example, bramble and hazel scrub – there is a strong nudge to more valuable and complex habitats, but in practice this is a habitat that can play an important role in delivering species richness within rewilding projects
- 3.0 favours hedgerow – it now reduces the difficulty penalty for all hedgerow habitat. Additionally, all hedgerows with trees benefit from an additional bonus over their non-tree counterparts. As a result, woody hedgerow is likely to be a more popular habitat replacement choice considering its value in Metric 3.0 and its relatively cost-effective creation.
- 3.0 still does not consider protected and locally important species. As a land based metric, the methodology relies on existing policy and legislation to protect important locations and fauna. Given the public attention to certain fauna like bees, badgers, dormice, and hedgehogs, Metric 3.0 is still not a substitute for professional ecological judgement.
Rollout
Metric 3.0 was launched six months ago, but the 2.0 version is still in use as a result of updating analysis already undertaken using the 2.0 metric. Where a project has already been assessed using 2.0, or is in the process of being assessed by 2.0, then the 2.0 version should still be used. While the changes to Metric 3.0 are a finessing of an established methodology, there could be significant differences between the metrics’ final outputs. Until all usage of the 2.0 metric disappears, attention should be given to which metric is being used, especially in cases where habitat was created in advance!
Use of Metric 3.0 will continue to overtake the 2.0 metric over the course of 2022, ahead of the mandatory BNG requirement coming into force in 2023 (as the 10% continues to be used as yardstick for achieving the broad brush NPPF goals).
So what?
Whilst Metric 3.0 addresses a number of flaws and concerns arising from the beta version, there are still grumblings that the metric does not go far enough. Whilst Metric 3.0 has not yet had enough time to become the solely used version and make an impact, DEFRA have already stated that they will consult on potential revisions to Metric 3.0 before the legal requirement for 10% BNG comes into force, so watch this space; version 4.0 may bring future surprises.
With thanks to Grace Pinault for assistance with this blog.
