Guidance on what biodiversity net gain (BNG) is and how it affects land managers, developers, and local planning authorities.
Applies to England
ThisBiodiversity draftnet guidancegain explains what will apply when (BNG becomes) mandatory.is Themandatory guidancefrom will12 continueFebruary to be updated.2024.
What biodiversity net gain (BNG) is
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In England, BNG is
Developers must deliver a BNG of 10%. This means a development will result in more or better quality natural habitat than there was before development.
Find out more about BNG in:
For the purposes of BNG, biodiversity value is measured in standardised biodiversity units.
A habitat will contain a number of biodiversity units, depending on things like its:
Biodiversity units can be lost through development or generated through work to create and enhance habitats.
Measuring biodiversity value
When considering biodiversity value, you should consult an ecologist. They will:
- measure the biodiversity value of your existing habitat
- advise on suitable habitat creation or enhancement for the land
Read guidance on using the biodiversity metric.
Calculating the units
There is a statutory (official) biodiversity metric, which
isyou amust wayuse ofto measuring:measure how many units: how many units how many units
Using the statutory biodiversity metric tool
provecalculate you have accurately calculated
This tool applies the statutory biodiversity metric formula.
Who BNG rules will affect
You need to know about the new rules if you’re a:
- of major
developments when BNG becomes mandatorydevelopments
- developer of small sites from 2 April 2024
- developer of nationally significant infrastructure projects from late November 2025
- of major
- land manager wanting to sell in the BNG market
- local planning authority (LPA)
Some developments are exempt from BNG
Find out what types of development are exempt.
Ways to achieve BNG: on-site units, off-site units and statutory biodiversity credits
Through site selection and layout, developers should avoid or reduce any negative impact on biodiversity. They must deliver at least 10% BNG, as measured by the statutory biodiversity metric.
There are 3 ways a developer can achieve
10% : .
- They can
enhancecreate and restore
- If developers can only achieve part of their BNG on-site, they can deliver through a mixture of on-site and off-site. Developers can either make off-site biodiversity gains on their own land outside the development site, or buy off-site biodiversity units on the market.
- If developers cannot achieve on-site or off-site BNG, they must buy statutory biodiversity credits from the government. This
mustshould be a last resort. The government will use the revenue to invest in habitat creation in England.
Developers can combine all 3 options, but must follow the steps in order. This order of steps is called the biodiversity gain hierarchy.
A developer cuts down some trees on the site. They must make up for this impact on the habitat, as well as delivering 10% BNG.
They must do a survey of habitat before development and use the statutory biodiversity metric to explore options. This tells them how to make up for the loss of the trees and what more they need to do to achieve 10% BNG.
If they cannot achieve the 10% BNG by creating and enhancing on-site habitats, they must buy off-site units.
If that is not enough to achieve BNG, they must buy statutory biodiversity credits.
10% BNG is required whether or not the development impacts existing
Creating, enhancing and maintaining habitats to deliver BNG
managerowner is legally responsible for creating or enhancing habitat, and managing that habitat for at least 30 years to achieve the target condition. Ifcondition. This applies if you make on-site gains or sell off-site gains on a site you own,own. you are the land manager.
What developers have to do
There is step by step guidance for developers.
Unless exempt, developers
of major developments once it becomes mandatory. .
You must try to avoid loss of
You should check if the LPA requires you to deliver more BNG.
For significant on-site gains, and all off-site gains, you must maintain the
BNGhabitats mustyou becreate maintainedor enhance for ata leastminimum of 30 years. ResponsibilitiesThe responsibilities will be set out in a legal agreement.
The following guides will help you:
- when you
buyuse off-site units, record the allocation of off-site biodiversity gains on the public biodiversity gain sites register,register, with the land manager’sowner’s permission
- estimate the cost of and buy statutory biodiversity credits if you’re unable to use on-site or off-site units
Exploring options and using the biodiversity metric
You should discuss your plans with an ecologist, who will measure the biodiversity value of your existing habitat and explore ways to achieve BNG using the metric tool.
If you have a small site, you don’t need an ecologist. You can either use the simpler small sites biodiversity metric tool yourself, or someone familiar with the site can do a survey and make a calculation. This could be the project manager, a gardener or a landscape architect.
Planning permission and biodiversity gain plans
When you apply to the LPA for planning permission, you will need to confirm whether your development is exempt from BNG.
If it is not exempt, you will need to
attach a metric tool calculation showing the site’s biodiversity value before development. You should also the requirement,
also aa legal habitat management and monitoring plan (HMMP)agreement. The terms of thesethe agreement will set out responsibilities for creationcreating, enhancing, monitoring and enhancement,reporting. You might also need a habitat management and monitoring andplan reporting. (HMMP).
If the LPA grants planning permission, you will need to create a biodiversity gain plan
. This is a document achieve .. You In your biodiversity gain plan you yoursome of your BNG decisions. decisions.
You must submit your biodiversity gain plan, including a metric tool calculation that shows how you will meet your mandatory BNG, to the LPA.
(See the guidance on the biodiversity metric .)
The LPA must approve your biodiversity gain plan before you can start development.
IfYou applicable,must themanage 30and yearsmaintain offor BNG30 managementyears, andstarting maintenancefrom startswhen fromyou complete the timedevelopment. theThis agreedincludes initialwhen habitatyou creationcomplete creating or enhancementenhancing isany completedon-site habitat (for example, after one year of tree planting, pond digging or seeding). seeding).
If you do not meet your BNG requirements, you might be in breach of planning conditions, planning obligations or legal agreement, and the LPA could take enforcement action against you.
What land managers have to do
‘Land manager’ refers to these different roles across BNG guidance:
- estate owner
- habitat bank operator
- facilities, property or estate manager
- land agent
- land advisor
- planning authority using land they own
- developer using land they own
Selling on the BNG market is a choice for land managers. It is a potential source of revenue and could fund nature recovery work on your land. You can sell off-site biodiversity units on your land to developers, who may need to buy these under mandatory BNG requirements.
Registering a site and recording units
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What LPAs have to do
Read guidance for LPAs.
You can get support from:
Updated to clarify that unless exempt, developers in England are required to provide 10% BNG on all habitats within the redline boundary of their development, whether or not they are impacted, and that separate arrangements apply to on-site irreplaceable habitat.
Updated box at top of page to state that biodiversity net gain (BNG) is mandatory from 12 February 2024 and removed the ‘draft guidance’ label. Updates to measuring biodiversity value and legal agreement information.
Removed links to draft statutory instruments as the final versions have been laid before parliament.
Updated the definition of the biodiversity metric, added ‘type’ to the list of factors the biodiversity metric measures, and added a link to more information about the biodiversity gain hierarchy.
The guidance has been updated throughout with information and examples about what biodiversity net gain means, how it is measured and how it can be achieved when it becomes mandatory.
Added a link to a feedback survey.