Defra has launched a new consultation on plans which would see developers required to deliver a ‘biodiversity net gain’ when building new housing or commercial development.

The proposed new rules require developers to assess the type of habitat and its condition before submitting plans. Carparks and industrial sites would usually come lower on this scale, while more natural grasslands and woodlands would be given a much higher ranking for their environmental importance.

Developers would then be required to demonstrate how they are improving biodiversity – e.g. through the creation of green corridors, planting more trees, or forming local nature spaces.Among the proposals the consultation is seeking views on is a plan to charge developers a levy to pay for habitat creation or improvement elsewhere in the rare circumstances where they would not be possible on site.

The Government has proposed that a levy could be calculated via further development of current freely available Defra biodiversity metric that Natural England will be testing with stakeholders alongside the consultation. Defra and Natural England are developing (with academia, industry and planning authorities) a new tool called an ‘eco-metric’ which aims to measure the ability of habitats to deliver ecosystem services. The research project will test how biodiversity net gain might be extended in future to cover other aspects of natural capital. 

The proposed draft Defra metric 2.0 will now flexibly incorporate green infrastructure features (such as green roofs and street trees) and rivers into the metric.

If mandatory net gain is introduced, where a development was unable to mitigate biodiversity loss on site or purchase the required biodiversity units locally, the developer would be required to pay a cash tariff on their shortfall against net gain obligations.

The consultation paper says that based on the application of the existing Defra biodiversity metric, a tariff on biodiversity units might be set between £9,000 and £15,000 per biodiversity unit. This would be adjusted in line with planned metric updates to avoid unjustified increases or decreases in costs.

The tariff range is based upon existing costings for habitat creation and estimates for administrative costs. The range will be reviewed in light of evidence from consultation responses and further engagement with stakeholders. Any final tariff rate would be a fixed price, set according to the development’s location.

While some developers have already been following a biodiversity net gain approach voluntarily, the proposed standardised, mandatory approach would give them clarity and certainty on how to improve the environment through development, while also considering whether any sites – such as small and brownfield sites – should be exempt from the rules.

Today’s action is described as the first step in the government’s ambition to embed the wider principle of ‘environmental net gain’ in development, to drive measurable improvements for all aspects of the environment such as air quality, flood defences and clean water.

Launching the consultation, Environment Secretary, Michael Gove, said:

“Our commitment to protecting and enhancing our natural world can go hand in hand with our ambition to build more high quality homes.

“Mandating biodiversity net gain puts the environment at the heart of planning and development. This will not only create better places for people to live and work, but ensure we leave our environment in a better state for future generations”.

In addition to upholding planning protections for sensitive sites such as ancient woodland and sites of special scientific interest, the consultation builds on the experiences of local authorities and developers who have already adopted net gain approaches.

This includes the Berkley Group who have committed to creating a net biodiversity gain within all their development sites and are currently working with London Wildlife Trust to build Kidbrooke Village in East London – a new 4,800 home village development that contains 20 hectares of parkland.

Elsewhere, Warwickshire County Council have trialled and implemented a system to ensure all developments lead to no net loss of biodiversity, with each development preparing a Biodiversity Impact Assessment prior to building.

Michael Gove said:

“By working collaboratively with water companies, tourism services, energy providers and waste experts, I have no doubt that profitable development could transform itself into a driving force of biodiversity enhancement.”

The consultation follows the launch of the revised National Planning Policy Framework in July which outlined stronger protection for the environment, ensuring wildlife thrives at the same time as addressing the need for new homes.

The proposals apply to development covered by the Town and Country Planning Act in England only - nationally significant infrastructure is out of scope of these proposals.

Deadline to submit responses to the consultation is 10 February 2019.

Click here to access the consultation document

Click here to access the consultation online