How is development affected by the Government’s plans on Biodiversity Net Gain?

Biodiversity Net Gain (‘BNG’) means a development has a positive impact on biodiversity. The current position is that planning policies and decisions should contribute to the natural environment by ‘minimising impacts on and providing net gains for biodiversity’. This is in accordance with the National Planning Policy Framework as policy guidance, rather than a mandatory requirement.

The introduction of the Environment Bill, as currently drafted, makes provision for Biodiversity Net Gain to be a condition of planning permission in England. A BNG plan must be submitted and a planning authority must approve it before a development is commenced. The biodiversity value of a development site must exceed the pre-development biodiversity value by 10%. This applies to developments under the Town and Country Planning Act 1990 and, more recently, development consent orders under the Planning Act 2008. In response to the Dasgupta Review published in February this year, the Government committed in June to delivering a ‘nature positive’ future (see the Government’s response here). As part of this, new Nationally Significant Infrastructure Projects in England will need to provide a net gain in biodiversity and habitats for wildlife.

BNG is calculated using the Biodiversity Metric, as produced by Natural England. The Metric includes intertidal and terrestrial habitats, although an approach to marine net gain for English waters has not yet been confirmed. An update is expected following Defra’s consultation towards the end of 2021. The Metric uses habitats as a proxy to describe biodiversity and these habitats are converted into biodiversity units, which form the ‘currency’ of the metric. Units are calculated using the size of a habitat and its quality. The Metric also takes into account the difficulty and associated risks of creating a new, or enhancing an existing, habitat. The calculation process is carried out pre and post-construction to produce a BNG figure that is comparative of the two.

The draft Bill sets out the ability for the Secretary of State to make provision for a register of biodiversity gain sites which operates so that land can be registered for habitat enhancement works to be carried out in an off-site location. These works would be required to be completed under a conservation covenant or planning obligation imposed on the development site. The draft Bill also sets out the biodiversity credit system, whereby the Secretary of State may allow developers to purchase credits for the purpose of meeting the biodiversity gain objective. The overall BNG figure can therefore be a combination of on-site habitat, the value of any registered off-site biodiversity gain allocated to the development, and the value of any credits purchased.

Given the climate and biodiversity crisis we currently face, for many developers and promoters, this is likely to be another step in a direction they were already going. Including Biodiversity Net Gain in development plans may result in fewer objections relating to nature conservation. The requirement will also promote more transparency and objectivity in the planning process by quantifying losses and gains in biodiversity. Promoters should therefore ensure their Biodiversity Net Gain figure is supported by sufficient evidence in their Biodiversity Net Gain plan.

Incorporating Biodiversity Net Gain into development plans now would not only assist with positive PR, but also potentially prevent costs increasing if this is factored into design plans early. It is advisable that developers and promoters familiarise themselves with the Defra Metric and guidance as published by Natural England, in order to be best-prepared and reduce risk of delay.