Net Environmental Gain Principle


The 25 year Environment Plan published in January includes a key commitment to embed an ‘environmental net gain’ principle for development, including housing and infrastructure. Specifically for the marine environment it also includes a commitment to reverse the loss of marine biodiversity and, where practicable, to restore it.

ABPmer's Technical Director, Stephen Hull considers how it could work in practice.

Hard-wiring the principle into decision-making
While the environmental net gain principle is framed in terms of using and managing land sustainably and in the context of the terrestrial planning system, the principle is equally applicable to the marine environment and possibly more so, particularly given that the seabed is a public asset in contrast to the predominantly private ownership of land.

As with many high-level Government policy statements, the subsequent detail will be important in clarifying the extent to which the environmental net gain principle will apply directly to marine development. However, as I see it, application of such a principle to the marine environment is likely to be essential if we are to reverse the loss of marine biodiversity. Indeed, hard-wiring such a principle directly into marine decision-making processes is more likely to deliver desired marine biodiversity outcomes than current processes which continue to result in marine biodiversity loss. Furthermore such an approach would be in line with the polluter pays principle – those using the marine environment should be responsible for maintaining and improving it.

Not just developments but activities as well
For the principle to be applied equitably, it would need to apply not just to development activities requiring formal authorization but to all uses of the marine environment, including activities such as fishing and shipping.

Some formal system of biodiversity offsetting would need to be established to govern the manner in which residual impacts could be offset. This could be based on natural capital accounting if there was sufficient confidence in the offsetting metrics. Such a system would need to be designed in line with good practice principles and the mitigation hierarchy, with offsetting used as a last resort, to avoid creating a ‘licence to trash’.

Regional restoration
Given the costs and scale of meaningful marine biodiversity restoration projects, adopting a strategic approach at regional national/level is likely to deliver better outcomes than a piecemeal project-by-project approach.

This could be facilitated through developer contributions similar to section 106 agreements under the terrestrial planning system. 

All of this is highly aspirational and poses many challenges in dealing with the complexities and uncertainties of our marine environment. As the policy develops over the next few years it is therefore important that all stakeholders with an interest in the marine environment engage with the process to ensure that any system adopted contributes to sustainable development of our marine environment.

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Stephen Hull

Business Development

(Policy and Planning)

+44 (0) 2380 711 849


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