Biodiversity Net Gain – How greening developments can benefit us all

Within England under the National Planning Policy Framework (NPPF), biodiversity net gain is strongly encouraged. As the government moves towards including a mandatory net gain requirement as part of the new Environment Bill, which will introduce changes to the Town and Country Planning Act 1990, BNG will move from a best practice ideal to a legal requirement in England. Developers will begin to see – as some already have - that beyond meeting compliance, incorporating high quality green space within their developments can have economic and social benefits, as well as environmental ones.

Understanding the real value of biodiversity

Biodiversity is the variety of species, habitats and ecosystems on our planet. In the past biodiversity has often been regarded as having only intrinsic value, in that it has value in and of itself, with no immediate value to humans. The conservation of biodiversity has therefore been considered as an ethical obligation due to humanity’s role in its decline.

However, these views are quickly changing with The World Economic Forum this year listing biodiversity loss as one of the top five threats to humanity in the coming decade. This is due to the fact that biodiversity provides us with many quantifiable benefits. The ecosystem services provided by the plants, animals and varied ecological features within our environment are invaluable, such as the cooling effect of trees in areas otherwise affected by the urban heat island effect, the improved flood resilience provided by rain gardens and wetlands, and the clean, breathable air provided by habitats.

Perhaps even more compelling than these benefits is the simple fact that humans enjoy nature. It is well understood that natural and green spaces, as well as developments following biophilic design principles (including water features, natural materials, sights and sounds of wildlife, foliage and natural light etc) provide a stress-busting effect for the people who inhabit and interact with these spaces.

Some people believe that access to green space goes beyond stress relief - the Japanese practice of Shirin-yoku (literally translated to ‘Forest bathing’) is a practice of relaxation, observing nature whilst disconnecting from the demands of every-day life, which is said to boost health and wellbeing. Perhaps more than ever during the current Covid-19 crisis many people have turned to their gardens and local natural green spaces as a resource for exercise and relaxation. Unfortunately, for a large number of people living in urban areas, there is a lack of easily accessible green spaces, such as communal gardens, parks and river walkways.

Although there are generally higher up-front costs of integrating biodiversity and biophilic design into developments, publicly available statistics suggest these higher costs can be fully or partially recouped; a study by the Office for National Statistics showed that houses and flats within 100 metres of public green spaces have a greater market value (an average premium of 1.1% over residences greater than 500 metres from green space). Additionally, just having a view of green space (such as public parks or playing fields) or water (rivers, canals, lakes or sea) boosts prices even further, with an average premium of 1.8%.

As of March 2021 the Land Registry’s UK House Price Index was showing that the average price of a property in the UK had risen by 10.2% to reach £256,405. This is in part driven by a shift in desirability for properties with access to the outdoors. According to the RICS UK Residential Survey, 83% of respondents anticipate demand increasing for homes with gardens, 79% for being near green space and 68% for more private outside space over the next two years. In combination with the sharp rise in house prices, house buyers seem to be prioritising the outdoors over being centrally located in more built up areas.

Cultural shifts and legislation change

The mandatory 10% biodiversity net gain requirement, as measured by biodiversity metrics published by DEFRA, will formalise the best practice approach taken by those developers already committed to environmental and sustainability objectives. The forthcoming Environment Bill will place these at the heart of the planning process, by inserting Section 90A into the Town and Country Planning Act 1990 with Schedule 7A ‘Biodiversity gain in England’ and mandating developers produce ‘biodiversity gain plans’ for all new developments.. Although the committee phase of the Environment Bill has been delayed significantly by the Covid-19 crisis – it is currently in the Report stage in the House of Commons – some elements of the bill came into effect from the 1st of January 2021 to coincide with the end of the UK’s European Union exit transition period.

Developers will face a number of challenges in implementing biodiversity net gain, primarily in balancing available developable land to be used for biodiversity compensation whilst delivering sufficient value to make the development viable. In the early stages of net gain becoming a legal requirement this balance may lead to some developers having to source and pay for a level of off-site compensation to meet the net gain target.

In the future the requirement for BNG will lead to improved site selection, with the needs for net gain being considered in early due diligence for site acquisitions. While we wait for the Environment Bill to be finalised, local authorities and statutory stakeholders are already asking developers to deliver net gain under the NPPF. Developers would therefore be well advised to incorporate biodiversity into developments currently under consideration. This will help to develop the skills, knowledge and commercial tools to implement net gain ahead of the legal requirement.

Under the Environment Bill, net gain will no longer be the preserve of the most environmentally conscious developers; all projects will need to understand their impacts on biodiversity, maximise nature-based solutions and balance design, commercial and environmental priorities. Ultimately, by prioritising biodiversity, multi-functional green spaces will become a focal point for an emerging form of development serving both communities and the environment.