Biodiversity Net Gain: A golden opportunity to demonstrate green leadership

Embracing BNG can fulfil multiple ESG goals, help secure community buy-in for your project, and create a lasting legacy for people and planet.

Under the provisions of the Environment Act 2021, a statutory 10% minimum biodiversity net gain will become mandatory for almost all land development in England from November 2023.

Meeting the new Biodiversity Net Gain (BNG) requirement will involve challenges and increase development costs. It also presents nothing less than a golden opportunity for the property and construction industry to make a sea change in its approach to sustainability.

At heart, BNG is a simple concept whereby a development must leave the natural environment in a measurably better state than it was beforehand. The driving principle behind BNG is the government’s preference for development on brownfield land where possible.

The new legislation is set to be pivotal for our planning system with the impact felt immediately by land owners and developers, who need to prepare now for the changes ahead. Ecologists and landscape architects can also expect to be kept busy for the foreseeable future in the rush to secure their services.

Some of the details about how BNG will be enacted are outlined below, though the industry is still awaiting exact guidance from the government about how the requirement should be delivered, and how it will be enforced. But, in a nutshell, the more biodiverse a site, the bigger the uplift in biodiversity needed to meet BNG. And this is not just a matter to be resolved during the development phase; BNG must be maintained for a minimum of 30 years post-completion. BNG can be achieved through an on-site approach, an off-site approach or a combination of the two. The upshot of the allowance for off-site BNG, which we discuss in more detail later, will be the creation of an off-site unit market.

Delivering environmental and social benefit through BNG

Bringing a site forward for development is no easy process, and the regulatory and planning environment can seem fraught with obstacles. But there is a real opportunity with BNG for the industry to contribute meaningful and lasting change for the better in the placemaking process.

Rather than see BNG as a type of tax to be avoided or minimised, BNG allows developers to demonstrate the wider value of their projects and sustainability leadership. Showing a clear commitment to, and evidence of, sustainability will boost your reputation for ESG principles and show how you are moving towards any stated Net Zero goals. The long-term benefits of embracing it are compelling from a commercial point of view too with investors increasingly looking for evidence of ESG principles in action, and, in the longer term, biodiversity increasing the value of land by helping to create high-quality space.

Securing a BNG of 10% necessarily means securing additional environmental benefits in the area, especially if the focus is on-site solutions. For example, through the provision of green walls, ‘living’ roofs or blue infrastructure such as wetlands and ponds. In turn, these features enhance the resilience of the site, aiding drainage and boosting soil health (which will no doubt become more of a focus in the future). Importantly, a development that enhances the natural environment serves to create places that offer new opportunities for people to connect to, and explore, nature, with all the benefits this entails for wellbeing and health.

Communicating the benefits of BNG

By embracing the need to provide extra biodiversity on your development site, you increase the chances of the community and planning officers supporting the scheme, helping to smooth your planning journey, saving time and money. It follows that it’s important that biodiversity benefits are clearly communicated as a key element of the development at the earliest stage possible.

Early collaboration with specialist advisers, especially ecologists and landscape architects, will allow you to be specific, and therefore credible, about how biodiversity will be created. Early engagement with the community can help establish what environmental enhancements local people would most like to see over the course of three decades.

Land development has had a negative effect on the natural environment for far too long. Biodiversity net gain is not just another hoop to jump through to secure planning. Through BNG, our industry has an opportunity to ensure that developments provide lasting benefits not only for wildlife but for people.

But these wider benefits need to be communicated clearly and in an engaging way from the outset of a project, and at each stage of its progress, if the opportunity that BNG presents to boost your reputation for ESG principles is to be maximised.  

Through our industry insight, extensive networks and integrated approach to communications, our specialist built environment team can help ensure that the work you are delivering to create BNG is recognised. From influencer engagement, to media relations, bespoke ESG content and digital campaigns, we understand how to reach the right audience, building understanding and driving positive change to create better places.

BNG: the detail

BNG will be introduced in phases with small sites having until April 2024 to comply with the regulations. Small sites are defined as those with one to nine inclusive dwellings on a site less than one hectare in area or with a site area of less than 0.5 hectares where the number of dwellings is not known. The government has made exemptions for self-build homes and householder applications to ensure that implementation is targeted towards developments with the most significant impact.

To ensure compliance with BNG, local planning authorities with planning oversight will receive £16 million in funding. This funding will be used to expand resources and upskill teams, including ecologists, to increase their capacity to oversee, and enforce, the new legislation.

How is BNG measured?

This is the million dollar question. Defra has developed a metric for calculating BNG and the calculation involves a comparison between the “baseline” biodiversity value of the site (which has been arbitrarily chosen as being the biodiversity value of the site pre-development) and the anticipated post-development biodiversity value. The baseline can be measured from a point in time some years in advance from the present to avoid any incentive to degrade the site’s existing biodiversity level.

The measurement of biodiversity value at each stage will take into consideration the distinctiveness, condition and strategic significance of three types of “biodiversity units”. BNG must be maintained for a minimum of 30 years post-completion.

How can BNG be achieved?

On-site solutions may come in the form of green walls, brown roof space or blue infrastructure such as wetlands and ponds. Developers will also have the option of tapping into habitat banks to secure gains from the start.

Where on site gains will not be sufficient, the legislation allows for off-site mitigation. This could bring opportunities to private landowners who will be able to capitalise on the new legislation through the “off-site unit market.” Natural England will publish a national register of biodiversity units on which landowners (and local authorities) can list land they have enhanced for developers to purchase or let. This market will also provide an opportunity for developers to monetise any excess of BNG beyond the 10% target.

Whilst this market establishes, the government will be offering a statutory biodiversity credits scheme. Where developers cannot achieve BNG gains either on or off-site, these credits could provide a last resort.

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Tori Madine
Tori Madine
Tori is a creative communicator and storyteller, translating clients’ strategic visions and complex stories into compelling content campaigns that deliver results.