Biodiversity Net Gain Legislation
Biodiversity Net Gain (BNG) is expected to become a mandatory requirement for many development projects in England from November 2023. UPDATED: BNG has now been introduced, effective from 12th February 2024. This legislation is being implemented under the Environment Act 2021 and will require developments in England to achieve at least a 10% increase in biodiversity. This increase can be achieved through habitat creation, habitat enhancement, or through the purchase of biodiversity credits.
The development projects to which this will apply are:
Those which are greater than 25m2 in size
In England only
Those due to occur above the mean low water level
Retaining and restoring different habitat types will help to tackle the biodiversity crisis, which poses a serious risk to human wellbeing without action being taken. By increasing biodiversity, we can build ecosystem stability and subsequently improve their resilience to the effects of climate change. Increasing the variety of species rather than solely increasing the population of individual species, we hope to address a major issue in England: monocultures and lack of resources for native species. The Environment Act 2021 makes amendments to the Planning Act 2008 and the Town and Country Planning Act 1990.
BNG legislation seeks to establish a market for biodiversity, by quantifying the value of not just an area, but habitat themselves (and the ecosystem services they provide). All habitat types are included, varying in complexity from bare ground to saltmarsh. It is hoped that by attaching a value to all habitat types, we can assign a monetary value to the priceless role that the ecosystems around us play in human lives
An example of this could be hedgerows, which break up the monoculture created by farming and provide a crucial habitat for species, but represents lost arable land in the eyes of a farmer.
Credit: Natural England 2022
The Biodiversity Net Gain legislation is coupled with the use of the Biodiversity Metric 4.0, Natural England’s calculation tool. The tool uses input data to determine the pre-development biodiversity value of the site, which is subsequently compared with the post-development biodiversity value of the site to determine percentage biodiversity gain/loss arising from development.
Pre-development value is determined by habitat distinctiveness, habitat condition and strategic significance of the development site/habitat, with these being determined by a “competent person”. This competent person will generally an ecologist, or someone with relevant experience conducting such assessments. The post-development biodiversity value of the site can be calculated by considering difficulty of achieving relevant habitat creation/enhancement, time to target condition, and in the case of offsite creation/enhancement, the distance from development site. Subtracting the pre-development biodiversity value from the post-development biodiversity value will determine percentage biodiversity gain/loss arising from development.
Our sister company Exo Environmental has recently been focussing their efforts on understanding the scope of the legislation, and working with the Biodiversity Metric 4.0, so that they can aid developers in achieving their BNG goals. For more information, feel free to contract them here.
Check out the CPD zoom recordings over on their YouTube channel by clicking here
