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Defra metric 3.0: what is it and how does it impact you?

4 Oct 2021

The latest and greatest in biodiversity net gain has landed. Do you know how it impacts you yet?

A step forward in Biodiversity Net Gain.

The Defra Metric 3.0 arrived what feels like a lifetime ago now, and it’s initiated a shift in the way that BNG is addressed.

But why should you care, you ask? Well, the Defra Metric 3.0 (and its predecessor) has largely become the go-to metric used to calculate whether a project has achieved the biodiversity net gain requirements set out in the Environment Bill and in many existing and emerging local planning policies. It’s literally how you will be measured and, ready or not, it’s here.

So, are you ready? We are.

What you need to know at a glance....

  • The metric for measuring whether a project obliges BNG terms has changed
  • If a project is in the process of, or has already been assessed by, V2.0 – you can still use it
  • Changes leave less room for inconsistency and interpretation
  • Delayed creation will help clients who are proposing phased developments
  • Some difficulty risks have been lowered
  • Images can now be submitted with assessments
  • Small sites metric is now live

We’ve been training our team to understand all the ins and outs, so we’re ready to support you.

Ready or not, here it is.

Before we get into the nitty-gritty of it, let us recap what Biodiversity Net Gain (BNG) means for anyone who is uncertain…

Biodiversity Net Gain is an approach to development, and/or land management that leaves nature in a measurably better state than beforehand.

Basically, it measures change by calculating the existing baseline value of a site and its predicted future biodiversity value. This includes any contributions provided through the creation or enhancement of habitats off-site.

What is the new Defra Metric?

The new Defra Metric (3.0) was implemented to help determine whether projects suitably oblige the terms of BNG in the Environment Bill, or not.

It is important to take note of the key differences between version 2.0 and what came into place earlier this summer.

However, to ease your urgent worries, we can assure you that the guidance from Natural England has been clear on previous or current assessments.

Cutting to it: no, you don’t need to redo these assessments. If a project has already been assessed or is in the process of being assessed by V2.0, then you can continue to use it.

That said, you’ll need to know the key differences we have found between the V2.0 and V3.0 for the future. So, let’s take a closer look.

The key differences of the Defra Metric 3.0

The Defra Metric 3.0 introduces the removal of both the connectivity multiplier and accelerated succession.

The connectivity tool added an extra layer to the unit calculator. However, there was never a strict methodology in determining the multiplier, so this was often left open to interpretation anyway.

By having it removed, this will take away the element of inconsistency throughout the industry.

Accelerated succession also triggered a lot of confusion throughout the industry. This is because for metric 2.0, an ‘error’ message would occur which could have thrown the whole calculation off.

Secondly, there was never in-depth information for the methodology/ reasons for usage. The introduction of the new tool has made it a lot more efficient, user friendly and beneficial.

Introduction of early creation and delayed creation tool

The most recent metric has also incorporated a new advanced creation tool which is brilliant news for enhancements that are to be done off-site or for habitat banks, as this gives these sites a heavier weighting.

The main thing to draw upon is that any habitat enhancements (either on or off-site) which are included within the metric and have already started (or are in the process of being completed) will be offered a higher weighting than if the enhancements or creation were done as part of the development works. This is because the habitat will already be on the way to its target condition (or, in some cases, it may have already been achieved!).

Secondly, delayed creation will help clients who are proposing phased developments. This is because, instead of ensuring net gain is achieved at each of the reserved matters stages, the promised deliverables can be produced at a later stage. However, it’s important to recognise that this delay will be reflected in the units obtained.

Lower difficulty risks

In addition, the creation and enhancement of some habitats have been made easier by difficulty risks being lowered. For instance, the difficulty of creation and enhancement for Other woodland broadleaved, Other coniferous woodland, and Other woodland mixed have all been lowered from medium to low. Moreover, there has been a reduction in time to target conditions for Other woodland broadleaved, other coniferous woodland and other woodland mixed in response to the Forestry Commission Woodland Specialists’ advice.

This means it is easier to tap into a solution whereby humans and nature can live in harmony, together.

Street trees count – and will be assessed!

Street trees have now been given the title of urban trees. This is great news for trees within a site that are not by a roadside. Trees also have condition assessments which may result in the post-development assessment having a higher value for trees.

A redefined balancing act

The ‘suburban/mosaic of developed/natural surface’ has now been removed and has paved the way for a 70:30 split which should be used across developed land and gardens. This will enable a more streamlined way to determine outputs when a proposal is at the outline stage.

For us, the condition assessment is now a lot more robust with points given to an overall score for a lot of habitats. This means a lot of the criteria is clearer and more explanatory – allowing for deeper, more rigorous assessments to be carried out. Plus, by making it more streamlined and rigorous, this will ensure a higher quality assessment and more reliable calculations on your first attempt.

Assessing correctly is essential to delivering great results and will significantly help in your application process.

A picture speaks a thousand words

The latest metric also allows you to add pictures to your assessments which is great for linking what we are talking about in our reports. This allows us to cut down on words, be more efficient and better illustrate what we’re talking about.

Small sites

Finally, the ‘small sites’ metric is now live (fanfares, please). This is suitable for residential developments with up to nine dwellings that are either:

1) less than a hectare

2) where the number of dwellings is unknown, but the development is <0.5 hectares

3) for all other developments <0.5 hectares where there are no priority habitats on site (excluding hedgerows and arable margins).

These small sites were previously exempt from the metric as it can be quite hard to deliver net gain on a very small proposal. A small site metric now takes into account that the footprint is going to be substantially lower than a large-scale development and so reduces the amount of ‘risk factors’ that are utilised to determine the unit value.

Lean on us

If you have land that needs assessing, leave it to one of our experts to do the paperwork. We love the work we do, and we love literally getting our hands dirty, so our clients get great results.

Get in touch with one of our team on 01285 831804 or email our Ecology Associate, Joseph Dance, here.

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