According to London's Natural History Museum, the UK is one of the least biodiverse countries in the world, having lost almost half of its wildlife and plant species since the industrial revolution. Enter Biodiversity Net Gain (BNG): the government's attempt to reverse this trajectory.
The legislation, introduced under the powers of the Environment Act 2021, aims to leave the natural environment in a measurably better state than it was pre-development. It will become a mandatory planning requirement from November 2023 for most developments. The draft BNG regulations are still awaited, yet we are seeing projects in which some councils are already introducing the requirement to provide a BNG of 10% or more through their development plans. Whilst this will certainly present challenges to developers, there is also scope for exciting opportunities for developers, funders, and landowners.
How will developers achieve BNG?
When the regulations come into force all planning permissions in England will be granted subject to a pre-commencement condition requiring the approval of a biodiversity gain plan, setting out how the biodiversity baseline of a development site will be increased by 10%. These habitat enhancement works, which can include on or off-site habitat improvements, as well as the purchase of BNG credits, must be secured for at least 30 years. The BNG requirement must be secured by a planning condition, planning obligation under a Section 106 Agreement, or a conservation covenant. For off-site biodiversity net-gain, they must be registered on the Biodiversity Gain Site Register.
How will BNG be measured?
Natural England published the 'Biodiversity Metric 3.1' in April 2022. This will be regularly updated and is expected to be the tool used to calculate BNG. It is important to note that biodiversity will be quantified by the number or types of habitats present on any given site, rather than by species present.
'Net gain' is calculated as a 10% increase on the biodiversity of the site prior to development. But what if there is zero biodiversity on-site? 10% of zero is zero, so does the requirement for Biodiversity Net Gain then fall away? The DEFRA consultation document (published in January 2022) suggests that, yes, brownfield developments that exclusively involve the redevelopment of buildings on hardstanding or sealed surfaces will be exempt from the BNG requirement. However, contrary to proposals under the December 2018 consultation, brownfield land as a whole will not be exempt from the requirement.
However, it is not a given that brownfield land has a lower biodiversity rating than other sites. Where brownfield sites have been left untouched for a long period of time, allowing nature to take over, the site may have developed a high biodiversity value. Furthermore, sites which have sparse areas of vegetation could be considered 'Open mosaic habitats on previously developed land' ("OMHPDL"), which is given "high" distinctiveness on Biodiversity Metric 3.1. Clearly then, not all brownfield land provides an easy route to securing BNG.
Exemptions
The DEFRA consultation closed on 5 April 2022, and its conclusions have not yet been published, however, following the release of the consultation in January 2022, the exemptions from the requirement have come into sharper focus. Permitted Development under the GDPO is likely to be exempt under the regulations, as are urgent Crown developments and householder applications.
Minor developments which impact habitat areas below a 'de minimis' threshold of 50 square metres are also proposed to be exempt. However, if priority or irreplaceable habitats are impacted, the exemption will not apply to the site, regardless of its size.
Some previously suggested exemptions are now off the table. These include temporary permissions and developments in conservation areas and national parks, as well as brownfield sites.
Small sites
All sites of whatever size are required to make a proportionate contribution of 10%, unless they fall under one of the exemptions outlined above. However, a small sites metric (such as that prepared by Natural England in April 2022) is likely to apply, to recognise the burden this puts on small site developers. Under the metric prepared by Natural England, a 'small site' is less than 0.5ha or up to 9 dwellings on sites less than 1ha.
Challenges and Opportunities
BNG will influence decision-making from the nascent stages of developments to well beyond completion. It will be imperative for developers to consider how they are going to achieve BNG as early as possible in the design process, to allocate land for on-site BNG if necessary (which is the preferred method of delivery). Furthermore, developers, landowners and funders will need to consider how they will maintain BNG for 30 years post-completion and factor this into business decision-making and budgeting.
Despite its challenges, BNG presents a whole host of opportunities to developers, landowners and funders alike. Firstly, as much brownfield land may have a low biodiversity baseline, the wise developer will seek out these sites, as the uplift will be a much easier and less costly task than on a site with a higher biodiversity baseline. Furthermore, developers may be able to take advantage of selling BNG credits. Where developers cannot achieve the required BNG on-site, or elsewhere in the local area, they will be able to purchase BNG credits for the enhancement of biodiversity elsewhere in England. This creates an opportunity for alternative land use where land is not viable for development; developers and landowners can carry out habitat enhancement works that meet the requirements, and 'bank' the units created, to sell BNG credits to developers. This would provide a stable income from the habitat land for at least the 30-year period during which developers must be able to guarantee BNG under the proposed regulations.
Whilst there is certainly a lot to bear in mind and much which could be subject to change, there are also a wealth of opportunities in this evolving sphere. Watch this space for further updates on how the proposed regulations develop, and if you require specialist planning advice, do not hesitate to contact a member of the Planning team.
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