The new custodians
“Mandating biodiversity net gain puts the environment at the heart of planning and development. This will not only create better places for people to live and work, but ensure we leave our environment in a better state for future generations.”
Former Environment Secretary, Michael Gove
In simple terms, Biodiversity Net Gain (BNG) refers to the idea that development should measurably improve the local habitats and wildlife surrounding it, rather than just seek to limit its damage on them.
This may seem an alien concept after decades of growth in which the development sector has, all too often, given the natural environment a low priority. But over the course of the last 18 months, the change of attitude has been astonishing. The sector is now being asked to pull off the ultimate balancing act: halting nature’s seemingly terminal decline at the same time as accelerating housing delivery.
Addressing nature’s ‘great thinning’
It is universally acknowledged that we need to dramatically increase the number of homes built in the UK. BNG seeks to address the risk that this increase in housebuilding also accelerates the loss of natural and semi-natural habitats, and the many critically important species that depend on them. By way of example, farmland birds declined by 56% in the UK between 1970 and 20151, and every square kilometre of the UK lost an average of 11 species of bee and hoverfly between 1980 and 20132. The rate of decline of most species is accelerating, not decreasing. Writer and journalist Michael McCarthy referred to this phenomenon as ‘the great thinning’. Others would see it as part of Earth’s ‘sixth mass extinction’.
With the UK already among the most nature-depleted countries in the world, continuing habitat loss is not an option. Part of the problem up to now has been a policy framework that gives strong protection to sites designated as environmentally sensitive, while adopting a very permissive attitude elsewhere. The argument has generally gone that if development can help to meet social and economic needs, a certain amount of harm to the environment can be tolerated.
Well, not any more. Both the National Planning Policy Framework (NPPF) and recently updated Planning Practice Guidance (PPG) strongly encourage biodiversity net gain through new development, and many local authorities are already pushing applicants to deliver this through planning applications. Before long, this will be mandatory for all but a handful of developments: the Government announced earlier this year that delivering net gain in biodiversity will be put on a statutory footing for the first time through a new Environment Bill. This significantly strengthens existing planning policy and builds on commitments in the ’25 Year Environment Plan’ to leave our environment in a better state than we inherited it.
In practical terms, this means developers will need to demonstrate the key moves that will be made to not just limit the damage to local habitats, but to enhance, nurture and maintain them. The requirement in the Environment Bill is for a 10% net gain on the pre-development baseline. This could be achieved by incorporating measures such as nature-rich green corridors, more multifunctional open spaces and a greater number and variety of trees on site. For new towns and villages, it might also mean investing in the natural environment on a broader, landscape scale. The possibilities are almost endless. It’s important to note that 10% is just a minimum requirement, which could be exceeded on many sites.
Are developers equipped to manage their new role as custodians of the natural world?
Some commentators have raised concerns about how developers and local authorities will cope with the new responsibilities. It will be a challenge, certainly.
But, there are very good reasons for the development sector to enthusiastically embrace its new role as a custodian of the natural world.
Local resistance to new housing is often predicated, at least in part, on an assumption that the area will be blighted with sterile suburbia and much-loved natural assets lost and degraded. More generally, public concern for the protection and enhancement of the environment has never been higher, brought into sharp focus by the visible effects of climate change and decades of unsustainable land and resource management. People are starting to see what science has been saying for some time. The built environment, and how we live our lives within it, should be central to this debate.
It follows that BNG could become the catalyst for rethinking how we plan and design places for the benefit of both people and planet.
Embracing the opportunity
Instead of treating the environment as a problem to be managed, it can be worked with to create places that are capable of being loved – places that facilitate healthier and more sustainable patterns of living, a strong sense of belonging and that people are happy to call home. With a creative approach and understanding of the bigger picture, development can be rooted in the landscape and connected to nature, with strong green infrastructure, varied ecosystem services, and a mutually supportive relationship between people and their natural surroundings. There will be change, of course, but that change need not be negative.
Embracing BNG could also raise development value to enable greater investment in infrastructure, community facilities and social housing – all crucial to delivering a positive social legacy, but too often sacrificed on the altar of viability.
LDA Design has tested some of these ideas in our masterplanning of Waterbeach New Town near Cambridge. We have recently worked with Defra and Natural England to design a new set of national green infrastructure standards.
If the Environment Bill is reintroduced in the next Parliament in its current format, the devil will be in the detail. For now though, it’s clear that progressive developers already welcome the prospect of a standardised, mandatory approach to biodiversity net gain because it brings clarity and a level playing field. It is also clear that there is an opportunity for biodiversity net gain to be so much more than the sum of its parts. These facts are unlikely to change.
Might we reach a point where we can say that our right to a home and to lead healthy, active lives does not come at the expense of the natural world around us?
Three things to keep in mind
First, BNG must be taken seriously. It cannot solely be left on the desk of the project ecologist to sort. It is a catalyst for rethinking places precisely because of its fundamental effect on how every project is planned, from putting together the land package to how the place created at the end of the development process will be managed and cared for over the long term. Solutions to challenges such as addressing biodiversity deficits while delivering other project requirements need the input of planners, masterplanners, urban designers and landscape architects too.
Second, biodiversity is just the start. Government has previously stated it wants to expand the net gain approach to include wider natural capital and green infrastructure benefits, such as flood protection, recreation and water and air quality. Local planning and combined authorities will target the enhancements that are needed most in their areas and developers will have flexibility in how they provide them. One of the first development areas to adopt this wider environmental approach will be the Oxford-Milton Keynes-Cambridge Arc. It seems likely that a more strategic approach to developing natural capital and GI is here to stay.
Third, the UK needs at the same time to start the rapid restoration, recovery and rewilding of already depleted habitats and ecosystems – all while adapting to the twin threats of a changing climate and diseases such as Ash Dieback that have the potential to radically alter some of our landscapes. The idea of ‘Local Nature Recovery Strategies’ proposed in the Environment Bill may go some way to achieving this if implemented, but probably won’t be enough when the problem is on a national scale.
None of us should rely on biodiversity net gain alone to solve the deep crisis besetting wildlife and natural habitats. After all, it has taken decades, probably centuries, to get to the low point we find ourselves at today, in the midst of a mass extinction. But the shift in approach we are witnessing in the UK is undoubtedly a positive start. Perhaps, we might one day reach a point where we can honestly say that our right to inhabit homes and lead healthy, happy lives does not come at the expense of the natural world around us having a fair shot at a secure future too.
Spencer Powell is a senior consultant at LDA Design.