Skip to main content

Lucy Stephenson, Environmental Data Analyst at CSX comments on the Government’s upcoming Biodiversity Net Gain (BNG) policy that goes live later in 2023:

Through my relatively short time working as an environmental data analyst at CSX, the recognition and importance of Biodiversity Net Gain (BNG) has grown remarkably. When I began my role in August 2022 BNG was a concept I, and many others, were unfamiliar of. Fast forward to now, and BNG is heavily discussed in environmental magazines, conferences, and online webinars in its run up to becoming mandatory in November this year.

Despite, there being many uncertainties surrounding BNG and how this will change future developments, it is very clear to me that off-site BNG provision will be essential in achieving the mandatory net gain in biodiversity. 

Biodiversity Net Gain recap

Biodiversity Net gain is a policy coming into effect in November 2023. The policy requires all developments in England to have a 10% net gain on biodiversity. Habitats are measured through a tool called Metric 4.0, as a way of quantifying the biodiversity. If the net gain cannot be achieved on-site, developers have the option to purchase biodiversity credits from an off-site provider to reach the required 10% uplift. 

On-site Vs Off-site

On-site BNG

Developers are encouraged to deliver the net gain within the red line boundary of a development site through habitat interventions such as green roofs and hedgerows. These habitats can contribute to increasing urban greenness and provide a range of ecosystem services. However, it is unlikely that the total net gain can be achieved fully on site every time due to reasons such as space availability and council specific requirements. Moreover, some Councils are requiring developers to reach a 20% net gain instead, and it is likely that more councils will follow. Additionally, updates to trading rules in Metric 4.0 mean that even if a development has achieved a net gain of 10%, the proposal cannot be accepted if trading rules are not satisfied. This is likely to happen if highly distinct habitats cannot be enhanced or retained post development.

Off-site BNG

Off-site BNG has several huge benefits. Firstly, these sites tend to allow more space for the creation of habitat mosaics which can be strategically located through providing connectivity or achieving habitats of significant importance to the local area. It is highly likely that these sites can create habitats of a higher distinctiveness in the BNG metric and produce a greater number of credits. Secondly, the habitats created off-site are much more likely to have a positive effect on true biodiversity and natural capital provision due to, again, the larger area and a reduction in human disturbance. Finally, off-site BNG projects provide landowners and farmers with an opportunity to improve nature, to be rewarded for doing so and to have access to the private market which many are restricted from.

Final thoughts

Despite concerns on reaching net gain fully on-site, I have noticed that many BNG discussions fail to acknowledge the importance of off-site BNG providers in ensuring upcoming targets are met. I recently attended a very insightful BNG workshop hosted by CIEEM. After 2 days of discussing everything BNG, the use of off-site BNG credits was only mentioned briefly once which was slightly worrying to me.

A combination of on-site and off-site BNG is essential for the policy to truly work. However, I believe there needs to be a greater recognition for the important role off-site BNG projects will have in developments achieving a 10% net gain and in achieving a wide scale positive impact on biodiversity. At CSX, we feel greatly motivated in encouraging the provision of off-site BNG. In the countdown to November, we continue to aid landowners into accessing the BNG market, whilst expanding our technology to accurately monitor biodiversity.

Photogrammetry result of a drone survey to 0.75cm GSD to assess and record the type, extent and condition of an area of mixed habitat vegetation.

Leave a Reply

%d bloggers like this: