Environmental net gain: An enduring development concept for resilient legacies
Chair of the Environmental Industries Commission's Natural Capital taskforce on why we should move towards environmental net gain.
Over the last 18 months or so, I have been working with a group of dedicated practitioners from across environmental consultancy, building development and utility capital projects and operations under the auspices of the Environmental Industries Commission Natural Capital taskforce.
Our work has been to grip the concept of Environmental Net Gain – what it is, how it relates to natural capital and ecosystem services and how it goes further than Biodiversity Net Gain.
The UK Government’s 25 year environment plan’s (25YEP) central premise was that development must leave our natural systems in a better place than they were before the development started. That is a tough ask and invites us to assess the current condition of natural assets, work out what (ecosystem) services they are providing to society and determine whether their restoration or improvement could enhance the benefits flowing to society in the context of development.
The next crucial step is to determine what impact the development has on the natural assets and their continued ability to provide services to society (e.g. air quality improvement) and where this is negative, to compensate for it by restoring and enhancing the condition of surrounding natural capital assets. The extent to which this can be accomplished within the development site perimeter is a function of the scale of the development and it may be that the enhancements have to occur adjacent to and well beyond the site, to fulfil the promise of the 25YEP. This latter element is Environmental Net Gain in a nutshell.
ENG goes well beyond Biodiversity Net Gain as it considers not only the diversity of species on a given plot, but the wider condition of and benefits flowing from the inter-related natural systems in a defined area, a function of the interaction between living things and the air, soil, rock and water matrix on which they thrive – you then layer on the benefits to society from that living matrix. When we disrupt this with development, we need to have a method for putting it right.
Our report provides some clear indications on how this can be done, relating both to the scientific approach and the resources and understanding needed within the organisations involved.
The chief takeaway for development and developers, be it for water, energy, infrastructure or housing is that the ENG concept can be effectively deployed as a design tool.
This is especially the case where a development is seeking to integrate green infrastructure or nature-based solutions for enhancing the resilience of infrastructure and the communities that depend on it. For example, a housing scheme might deliver Biodiversity Net Gain, while also responding to a need for flood risk alleviation and local air quality improvement – the wider Environmental Net Gain approach provides a framework for nesting all these public benefits, which could simultaneously restore and enhance the functioning of natural systems in the locale.
So, taking an ENG approach can actually help reveal opportunities for community and ecosystem enhancement that might have been missed, had a purely Biodiversity Net Gain approach been adopted. A natural follow-on is that in taking a combined BNG and ENG approach, the most valuable habitats are retained. They provide a resilient core for the nature recovery networks proposed in the new Environment Bill.
On a final fiduciary note, the Net Zero Carbon and the ENG agendas are in my view closely aligned. With the flood of finance flowing from the carbon offsetting resurgence, some nifty financial planning could enable the development of climate finance instruments – Green Bonds or similar – to connect Environmental Net Gain and Net Zero developments, thereby creating a sustainable financial flow for the maintenance of enhanced natural systems in perpetuity.
Robert Spencer is Director, Sustainable Development at AECOM UKI and Chairman of the EIC Natural Capital Taskforce.