The Impacts and Outcomes of Biodiversity Net Gain Legislation One Year After Its Implementation

The Biodiversity Net Gain (BNG) legislation was introduced in the UK with the objective of ensuring that all development projects contribute positively to the environment. Enforced under the Environment Act 2021, the legislation mandates a minimum 10% improvement in biodiversity following development, promoting sustainable growth and ecological preservation. Now, one year after its implementation, it is essential to critically assess the impacts, outcomes, and broader implications of this pivotal piece of legislation.

The primary objective of the Biodiversity Net Gain legislation was to establish a way to ensure that habitats for wildlife are left in a measurably better state than they were before the development.

A year on and the industry has faced challenges, key issues include the need amongst stakeholders to understand the concept and how this works in reality. It is difficult to achieve the gains on some sites and there is an inconsistent approach from authorities on off site gains. There are clear impacts in terms of viability and resource constraints in meeting BNG requirements. There are also questions around managing long-term monitoring and maintenance obligations to ensure that biodiversity gains are sustained.

It is still too early to realistically measure the success of the legislation. In practical terms, our experience so far has been mixed. We have both promoted schemes that have delivered 10% plus gain on site with ease which have been welcomed and recognised as a planning benefit, whilst also fostering relationships between developers and those promoting habitat banks for off site gains. Equally, we have had difficulties where one particular local authority is reluctant to accept off site gains that are not within the same ward as the proposal.

There is some criticism in the industry press that there is a high percentage of applicants selecting 'no' when asked if BNG applies to their site. Exemptions remain a big part of the debate with some authorities requesting written proof from a ecologist that the site is ‘de minimis’.  Ecologists in both the private sector and at Local Authority level are stretched with Conservation Covenants and S106 agreements taking time to complete.  

The BNG legislation was never going to be an overnight success, it will take several years to fully understand the positive impacts on biodiversity.  Moving forward, continued commitment, iterative learning, and enhanced collaborative efforts will be crucial to realising the full potential of BNG and securing a healthier, more resilient environment for future generations.