Explaining Biodiversity Net Gain

Explaining Biodiversity Net Gain

You may have noticed the phrase ‘Biodiversity Net Gain’ appearing more often recently. It’s because it’s one of the key phrases in the government’s proposed Environment Bill.

In Spring 2019, following a consultation period, it was announced that Biodiversity Net Gain would be included in the Environment Bill, the legislation being introduced to replace the EU legislation that will no longer apply in the UK from 1st January 2020. Biodiversity Net Gain will become a compulsory element of planning and development work in England, but as yet, there isn’t complete clarity as to what will actually be required.

For the purposes of the government’s consultation, Biodiversity Net Gain was defined as:

“an approach which aims to leave the natural environment in a measurably better state than beforehand.”

The consultation aimed to find out if a standardised approach is needed, and how this should be put into practice and measured. Although the consultation has ended, the Environment Bill is still working its way through Parliament so it’s not yet clear how Biodiversity Net Gain will be put into practice.

Is Biodiversity Net Gain new?

Biodiversity Net Gain is essentially the practice of leaving a habitat in a better condition than it was before human intervention such as development work. It’s a practice that is already in use, but there is not a standard method of measurement.

Generally, a survey needs to be carried out before any work is started and another after completion. Various aspects are measured to produce ‘biodiversity units’ to provide a comparable before and after score.

While this works for individual developments, it can make it difficult to compare schemes. Defra’s own biodiversity metric is the most commonly used, but many organisations and local authorities have their own systems. Each planning authority also works independently when it comes to assessing and enforcing the metrics.

Biodiversity Net Gain can also be misleading when it comes to more complex habitats – while a common species thrives, an endangered species could be severely affected by development work. However, the overall net gain could be seen as positive depending on how it’s measured.

Should we be using Biodiversity Net Gain?

Embedding this concept in law, regardless of the potential pitfalls, can only mean an increase in environmental protection. As it stands, the Environment Bill will make a net gain of 10% for at least 30 years compulsory on most new developments. With lots of plans to increase housing and the related social infrastructure, it should lead to a big increase in the Biodiversity Net Gain across the UK.

Areas deemed ‘irreplaceable habitats’ will be given special protection to avoid risking endangered species.

Defra’s biodiversity metric is the one put forward for standard use, and this takes into account the condition of the land, how distinctive it is, how significant it is and how it connects to other nearby habitats. These are all evaluated according to a scale, and the resulting figure is multiplied by the size of the site to give a score.

The same procedure will be used at the end of the development work to give a second score.

Regardless of the initial score, any extra protections put in place for certain species, habitats and designated sites will always take precedence.

Using this model as standard should make it easier for anyone applying for planning consent to understand what will be required, and should strip away lots of the quirks which have crept into the requirements of individual planning authorities.

Ongoing biodiversity monitoring will mean that this new standard model will be used to map current levels across the country. This will help to identify areas which could benefit from extra support, as well as providing a record of an area in case of illegal developments – it will be easier to measure the impact illegal activity has had, and so penalties can be set appropriately.

Are there negatives to this approach?

Once the Environment Bill becomes law, there will be a two-year transition period. With no indication as to how long it’s going to take for the Bill to get Royal Assent, there’s also no way of knowing when these measures will start to be used.

Defra have also acknowledged that there are some other areas which are important to consider but which aren’t included in their metric, such as what the land means to the people nearby and how it contributes to the wider ecology.

The government has created a list of exemptions to the compulsory 10% biodiversity increase, including major infrastructure projects, some urban brownfield sites and small developments covering less than half a hectare or with fewer than 10 residential units.

These exemptions could equate to huge swathes of land turned over to development with no requirement to protect the natural habitats.

Another potential loophole has been created through a ‘compensation’ scheme, where biodiversity work can be carried out at a site away from the development project if it’s believed that biodiversity losses are unavoidable. In some cases, this could mean that a habitat would be completely destroyed, whereas under previous legislation, some of it would have had to remain.

Particularly important habitats will continue to be protected, such as ancient woodlands, for example, but this will only apply to some exceptional areas.

As with all planning and environmental legislation, this only applies in England – devolved governments will make their own decisions. Architects, developers and others could be faced with different requirements and processes in different countries of the UK.

What’s next?

While we know that Biodiversity Net Gain is likely to become a compulsory part of planning legislation, it’s impossible to know when. No one knows how long it will take for the Environment Bill to be passed into law, although recent indications suggested it will be enacted in spring 2021.

However, while we wait, some larger developers are preparing for the change by increasing the work they do to protect habitats and enhance areas near their developments.

Although infrastructure developments are exempt and developers might make use of off-site ‘compensation’, we know that areas of special interest will still be protected, and overall there seems to be a desire to continue looking after biodiversity in England.

To find out more about Biodiversity Net Gain and how to incorporate it into your plans email enquiries@engain.com.

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