Biodiversity net-gain (BNG) is a development approach which seeks to improve a site’s biodiversity value. BNG has quickly become an important tool to make sustainable decisions easier, leading the way towards a whole new development paradigm. We are diving into the BNG approach to explore how urban planners, designers, decision makers, and landowners can use BNG to gain positive outcomes from their development plans, while also help put a halt to global biodiversity loss.
When Milford attended the Build for Biodiversity conference in Copenhagen a few weeks ago we were introduced to the Biodiversity net-gain (BNG) approach as part of the inspirational conference program. In the last couple of years, people in the construction industry have become more familiar with BNG, and the approach have become widely popular, especially in the UK, where BNG has also found its way into the UK’s legislation act. Furthermore, BNG has the potential to be an important driver of change in the construction industry to ensure the halt of biodiversity decline towards 2030.
Throughout this article we will explain how BNG works and can become useful for everyone working with planning, designing, or investing in urban development projects.
In essence, BNG is an approach to development, land and marine management that leaves biodiversity in a measurably better state than before the development took place. BNG can be achieved on-site, off-site or through a combination of those.
BNG has been underway especially in the English planning system since 2019 where the Environment Act of UK delivered a mandatory 10% biodiversity net gain for all landowners, also meaning that any off-site net gain must be protected for a period of at least 30 years.
BNG consists of a metric system tool where calculated biodiversity unit scores are used as a proxy for the relative biodiversity worth of a habitat or site.
1. The habitat size (how big or small is the site?)
2. The condition of the habitat (based on the biodiversity value of the habitat relative to others of the same type)
3. The distinctiveness or importance of the habitat (based on the type of habitat and its ecological importance)
4. The location of the habitat (whether the habitat is in a strategic important area, or in connectivity to other relevant areas)
It is important to note, that while the metric tool is available for free download online, it requires ecological expertise from a biologist or similar to classify the right condition of the habitats and biological classification to ensure the quality of the outcome.
The generated biodiversity unit score derived from the calculation is used to put down a baseline, which can be used to inform design and decision making for planning the further development of the site.
Biodiversity is under high pressure and declining worldwide, and it has caused a heightened political concern, which has moved the subject up on the agenda to prevent further declines. If not addressed in time, biodiversity loss can cause irreversible damages to ecosystems and lead to negative challenges for future livelihoods and quality of life, according to the latest global assessment report from IPBES (Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services).
Naturally, the question for the construction industry is how to lead future economic growth and urban development which at the same time accelerates nature recovery in order to minimise the challenges from biodiversity decline. Something that will also help maintaining a secure future economy and provide healthy ecosystems.
BNG gives a new opportunity for developers, landowners, and local planning authorities amongst others to encourage the enhancement of nature recovery and communicate its positive outcomes for the benefit of future urban habitants and their wellbeing.
Urban planners/designers – Can use BNG to inform the design and lean towards nature-based solutions early in the design process.
Landowners/Investors – Can use BNG to establish a baseline to reveal long-term income opportunities and/or to identify potential net gain values leading to an increased attractivity of the site and positive natural capital assets.
Local planning authorities – Can use BNG to inform planning strategies and make sustainable decisions easier to support and communicate wider biodiversity objectives. It also gives the opportunity to include local citizens and get them involved in climate related adaptation projects, which stimulates local communities and creates green jobs.
Urban habitants – Getting familiar with the concept and the biodiversity metric tool helps urban habitants learn about the positive outcomes which promotes health and wellbeing by connecting with nature.
With BNG it is easier to undertake a baseline assessment of any site before development and by using the biodiversity metric tool to forecast a proposed outcome.
It is also important to note, that while the results from BNG can be used to improve design and communicate its gains, BNG aims to encourage an enhancement, not a complete transformation.
To sum up, BNG is a way to measure and communicate the positive outcomes from nature recovery, and to inform the design and development process towards more nature-based solutions. BNG is a valuable tool and can be a driver for change for people in the construction industry to make sustainable decisions for future urban development and to create attractive urban places, which increases financial and natural capital asset values.
As BNG has now become mandatory in the UK through the Environmental Act, we might see that other countries will get inspired and that BNG will become an integrated part of all new development plans on a global political level.
At Milford we support the positive movement of BNG to make future cities greener and liveable. We want to become a part of a new urban development paradigm that uses biodiversity as a positive driver, increasing the well-being of urban habitants and more resilient cities.