Biodiversity Net Gain (BNG) can be understood as development that leaves biodiversity in a measurably better state than before

BNG affects all town and country planning act developments in England and was introduced as a concept in the Environment Act 2021. BNG will become law following the implementation of secondary legislation anticipated in November 2023. BNG will not apply for ‘small sites’ – nine development units or less or 0.9 hectares or less until April 2024. Nationally Significant Infrastructure Projects will also only be affected by BNG from 2025.

What does this mean for development?

BNG means that all new developments will have to provide a biodiversity gain plan with their planning application detailing how the 10% uplift will be delivered. BNG can be delivered in three ways:

• On-site: Where a 10% uplift in BNG is delivered solely within the red line boundary of the development

• Off-site: Where the required number of BNG units is sourced form a local ‘habitat bank’ or ‘donor site’ for a price agreed between the landowner and developer to satisfy the 10% uplift.

• Statutory credits: This is a last resort and should only be implemented if BNG cannot be delivered through on-site and off-site measures. Developers can submit payments to the government which will be diverted into local government biodiversity projects.

Statutory credits have been priced so as to disincentivise their use and to stimulate the off-site BNG market place.

BNG will be calculated using the most recent version of DEFRAs Biodiversity Metric, currently version 4.0. This will be used across England to quantify habitat loss and gain.

Should BNG units be purchased from an off-site provider, the provider is agreeing to manage the site in accordance with a pre-agreed management plan for 30-years – the minimum length of a BNG agreement.

A biodiversity gain plan will also show how the mitigation hierarchy has been followed for the development site:

1. Avoid: Any negative impact where possible

2. Minimise: detrimental onsite measures that cannot be avoided

3. Restore: areas within the developent for biodiversity enchancements – this can contribute to on site BNG

4. Offset: should additional biodiveristy be required following restoration, BNG should be sought locally in order to satisfy the 10% net gain obligation

Often delivering BNG on-site is not always possible and can put strains on housing density and therefore financial viability for a development. Consequently, off-site BNG units can provide a means of complying with requirements whilst enabling devlopment.

How Does this Affect Tourism, Leisure and Events?

BNG presents a manageable hurdle to the TLE sector whilst benefitting the environment.

New development, if over the threshold area, will have to deliver a 10% uplift in biodiversity net gain, which may present additional cost for the project developer. However, with sound planning advice BNG can often be delivered within the development site. If diversification or change of use is planned so as to result in an uplift in biodiversity, this should be quantifiable so as to satisfy local developer BNG obligations.

For example

A golf course looking to decommission and rewild as part of a wider project of creating a health retreat would be able to measure their existing biodiversity levels as a golf course, quantified as BNG units. Following this, the proposed rewilded habitat can also be measured and the increase in BNG units is then measurable against any diminution in biodiversity from the planned development.

The BNG Market

The immediate market for an off-site BNG unit provider is within the same Local Planning Authority (LPA). BNG units can be sold to neighbouring LPAs and ones further afield, but a reduction factor is placed on these units of 25% and 50% respectively. The purchaser of these units has to make up the difference by purchasing enough BNG units to satisfy the additional requirement. This is to incentivise local delivery.

BNG unit values vary subject to the habitat that is being traded. There are currently few comparables to use, but values look to range from £20,000 to £30,000 per medium distinctiveness BNG unit, with geographic variation. The BNG market works on a supply and demand model, leading to a wider range of prices for increasingly rare habitats.