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When will Biodiversity Net Gain be Mandatory?

Biodiversity net gain (BNG) will be mandatory by the end of 2023, but what exactly is BNG, and how can developers prepare?

What is biodiversity net gain?

Biodiversity net gain (BNG) is already well-known in legislation across the UKs local planning authorities. However, BNG it is set to become a mandatory part of all development and planning applications at the end of 2023.

BNG refers to the process in which a project or development site has to consider its impact on the surrounding irreplaceable habitats and environment. This mean that developers must adapt their planning processes to ensure no damage is done to any local ecosystems.

A biodiversity net gain plan ultimately aims to ensure a developed area is left in a measurably better state for the environment than it was before development began. This could be achieved through creating or enhancing local habitats surrounding and within the development. Implementing BNG can be done both on site and off site.

when will biodiversity net gain be mandatory

Local planning authorities are frequently asking developers to meet the requirements for BNG in hopes that the developers will demonstrate how the project will benefit the environment around them. BNG essentially acts as a planning condition as well as a policy requirement for planning consent. As such, complying with biodiversity net gain is a significant factor in whether planning permission is granted or denied.

When will biodiversity net gain be mandatory?

Following the Environment Act 2021, local planning authorities must require all permissions they grant to achieve at least 10% biodiversity. A provision for secondary legislation has been put into place from the act, which will set a date in which the mandate will come into force. The mandate is predicted to come into force in late 2023. The 2021 act gives a two-year transition period for authorities to get their policies and processes in place before it becomes mandatory.

The current national policy in England, The National Planning Policy Framework (NPPF) Paragraph 179 states:

“To protect and enhance biodiversity and geodiversity, plans should:

“Identify and pursue opportunities for securing measurable net gains for biodiversity.”

Paragraph 180 states:

“When determining planning applications, local planning authorities should apply the following principles:

Opportunities to improve biodiversity in and around developments should be integrated as part of their design, especially where this can secure measurable net gains for biodiversity”

Various Local Planning Authorities have been requesting the assessment for the past few years already. Many have introduced or are currently beginning to amend local developers’ processes to ensure they meet the required standard as part of Local Policy.

The Act will require the key points:

  • Developers must deliver BNG at a minimum of 10% through their schemes. This will be measured through a metric, currently Biodiversity Metric 3.0. This tool can help to identify your biodiversity unit score and translate it into the standards of local planning authorities.
  • A developer will need to demonstrate how biodiversity gain will be delivered on developed land. This will be demonstrated through the production of detailed Landscape Planting Schemes, Landscape Management Plans and Monitoring assessments for on and/or off-site.
  • A mitigation hierarchy is to be followed and demonstrated to avoid, minimise or compensate. If it is not possible to compensate on the development site, then offsetting will be required elsewhere.
  • Developers will have to guarantee the biodiversity gain is maintained for at least 30 years (as outlined in Landscape Management Plans).
  • New “local nature recovery strategies” will be prepared to geographically cover England by “responsible authorities”. This will encourage habitat creation and enhancement in the right places.
  • Conservation covenants will be a mechanism used to deliver this (this approach is in preparation by Defra and Natural England).
  • A national register of land used for biodiversity gain will be established. This will involve setting up a new biodiversity credits market.
  • Metrics are only concerned with habitats and do not take protected species into consideration.
  • Other ecological legislation and policies still apply.

The aim is to get developers to think about mandatory biodiversity net gain during the initial land acquisition stage in order to avoid changing calculations once designs have already been produced. Having to redraft plans will typically lead to delays, unpredicted financial costs and difficulties with planning application determinations.

How can Collington Winter Environmental assist?

Taking measures to increase biodiversity net gain within your development project will improve your chances to gain the required planning permission from your local authority when biodiversity net gain is mandatory. Getting ahead of legislation and keeping up to date with current and upcoming laws surrounding the Environment Bills will ensure your development project runs as smoothly as possible.

At Collington Winter, our team of ecologists are experts in the field of biodiversity net gain and can keep you up to date with new and changing legislation. As regulations can vary across local authorities it is important to instruct a qualified ecologist to ensure you are following the correct rules.

Our team’s experience and qualifications in BNG means we can support our clients pre and post development in order to reach the required mandatory biodiversity net gain bracket that is becoming law in autumn 2023.

To find out more how our team can help you with your biodiversity plans then please do not hesitate to get in touch with us to discuss your queries. Contact us using the details below.

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