I am proposing a Major Development, what do I need to do?

If your development proposal is classed as 'Major Development' (as defined by Government in the The Town and Country Planning (Development Management Procedure) (England) Order 2015 (external link)), then from 12 February 2024 it has become mandatory for such development applied for on or after that date to deliver a Biodiversity Net Gain (BNG) of at least 10%. 

Full details on what you need to do to comply with your BNG obligations are set out in national guidance (external link).

This webpage only covers some of the essential requirements to get you started on what is needed, and when it needs to be done. However, this webpage is not a substitute for the full legislative requirements and national guidance which you will need to comply with.

The Statutory Biodiversity Metric

The Statutory Biodiversity Metric (external link) is the fundamental aspect of the BNG system, so you need to familiarise yourself with what it is and what information is required. It is a national requirement that it is completed by a competent person. 

The end goal you must achieve is for the Metric to demonstrate that at least a 10% BNG will be achieved. It is vitally important that from the outset it is understood that each habitat type identified in the metric needs to deliver a like-for-like or better of that type of habitat, as defined within the Metric. This means you cannot provide a high degree of gain of one habitat type to 'cancel out' a loss of another habitat type. That will not be accepted. For example, a 100% increase in hedgerows to cancel out a 50% decline in waterways would not be acceptable.

The Biodiversity Gain Plan

The Biodiversity Gain Plan is another fundamental aspect of the overall BNG system. The Biodiversity Gain Plan shows how you will achieve BNG, and must include a metric tool calculation. It will also include how you intend to manage and maintain the gains for 30 years, starting from when you complete the development.

However, it is important to note that the Biodiversity Gain Plan is something you submit to the Local Planning Authority (and thereafter gain approval for it) after you have got planning permission. You can not gain approval of your Biodiversity Gain Plan at the same time as planning permission. 

A template Biodiversity Gain Plan (external link) is available from Government.

What to submit and when

There are certain things that you must submit with your planning application, and certain things you can only (but also must) submit after you have received planning permission. 

When you submit your application, of fundamental importance is the submission of a pre-development biodiversity value of the on-site habitat including the completed metric calculation. However, there are a number of other matters you must submit, including various statements about the site and its present and past biodiversity. A useful checklist (external link) can be found in national guidance. If all these matters are not included with your submitted planning application, then we will not validate your application.  

Whilst the above are compulsory matters to submit, you may also wish to submit a draft Biodiversity Gain Plan, a draft completed full metric and a draft Habitat Management and Monitoring Plan (HMMP) at the planning application stage. This might help speed up the decision making process overall. As they are only draft, you can show different options that you are considering. For a template HMMP please view the Natural England template (external link)

After you have received planning permission, you you will then need to submit your final Biodiversity Net Gain Plan, including a fully complete Metric and HMMP. Unless otherwise agreed, the Council has 8 weeks to approve or refuse the Plan.

Conditions and Legal Agreements

Significant biodiversity gains on-site and all biodiversity gains off-site will need a s106 agreement to ensure that robust and enforceable measures are in place to deliver the BNG obligations for at least 30 years. Other on-site biodiversity gains that are not significant will likely be secured via a BNG condition.

Comprehensive step by step process for developers

For a fuller checklist and guidance of all the steps associated with meeting your BNG requirements, please refer to national steps for developers (external link) guidance.

Alternatively, a Technical Guide (external link) has been produced by CIEEM, IEMA and CIRIA which aims to provide a simple ‘how to’ guide on mandatory BNG. It is primarily for CIEEM, IEMA and CIRIA members involved in BNG but is likely to also be useful for planners, developers, architects, engineers, landscape architects and land managers. The Council may refer to it from time to time, if helpful to explain to wider stakeholders how and why we are implementing BNG procedures.