Biodiversity net gain and related terminologies explained
[edit] Origins of global biodiversity interventions
The creation of the United Nations Framework Convention (UNFC) at the Rio Summit created three intrinsically linked strands, the first of which is possibly most well known, while the second relates directly to biodiversity:
- Convention on Climate Change (UNFCC), most commonly referred to as COP or UNCCCOP.
- Convention on Biological Diversity (UNCBD or CBD), also sometimes referred to as COP, BIOCOP, or EXCOP.
- The UN Convention to Combat Desertification (UNCCD), also sometimes referred to as COP.
In 2020, a UN report noted an unprecedented rate of biodiversity loss, with around 1 million species threatened with extinction. The report highlighted the need for policy interventions, including biodiversity offsetting and mitigation measures.
[edit] Origins of UK biodiversity interventions
The Environment Act, based on the Environment Bill (originally published in July 2018 but delayed due to Brexit), received royal assent on November 9, 2021. The Act followed UN reports and increased government awareness, including studies showing the UK having lost more biodiversity than any G7 country. The Environment Act replaced many aspects of UK legislation that were covered by European law prior to Brexit and were no longer applicable after the UK left the European Union.
The general aims of the Environment Act remained focused on reducing landfill, improving air and water quality, and protecting biodiversity and wildlife. It set out a number of components relating to biodiversity net gain (BNG), including amending the Town and Country Planning Act (TCPA), requiring a minimum 10% biodiversity gain, significant on- and off-site habitat to be secured for at least 30 years, an on- and off-site delivery approach with a biodiversity credit scheme, and a national register for net-gain delivery sites.
[edit] When does Biodiversity Net Gain (BNG) apply?
Biodiversity Net Gain (BNG) is mandatory for major developments from February 12, 2024, and for small sites or minor developments from April 2, 2024, and for Nationally Significant Infrastructure Projects from 2025 (planned). Minor residential development are defined as one to nine dwellings, inclusive, on a site having an area of less than one hectare, or, where the number is not known, a site area of less than 0.5 hectares. For non-residential, where the floor space to be created is less than 1,000 square metres or where the site area is less than one hectare. Developments that exceed this, so 10 dwellings or more, are defined as major developments, with these exemptions; development impacting a habitat area below 25 m2 or 5m for linear habitats such as hedgerows, householder planning applications, and small scale self-build custom buildings.
[edit] Biodiversity Net Gain in brief
Biodiversity Net Gain (BNG) is based on the statutory biodiversity metric of biodiversity units (area, hedgerow, and watercourse units) that need to be calculated prior to a development taking place, along with how many units are needed to replace units of habitat lost through the development.
Developers need to achieve a 10% BNG through the creation or enhancement of habitats to be evidenced via a biodiversity gain plan, which can be submitted to the local planning authority after the planning application has been approved. The assessment needs to be carried out by a professional ecologist, according to the guidance and in line with any Local Nature Recovery Strategy (LNRS), and the biodiversity improvements are then recorded in the publicly available biodiversity gain site register. The approach taken to biodiversity protection is referred to as the mitigation hierarchy.
[edit] Mitigation hierarchy
The mitigation hierarchy is a decision tree to help effectively manage the impact of developments on biodiversity. The principles of biodiversity net gain generally adopt the same approach.
- Avoiding the impacts of a development on biodiversity through location, scale or timing is the first priority.
- Minimising a developments impact on biodiversity through approach and design should be prioritised next.
- Restoring habitats damaged or degraded by a development such as replanting or reseeding next.
- Offsetting refers to compensating unavoidable impacts of development, possibly elsewhere on a different site.
- Contributing financially to wider conservation efforts is seen as a last but viable option in certain cases.
[edit] Biodiversity net gain metric
The biodiversity metric is an official and statutory term referring to a way of measuring biodiversity value for the purposes of the Biodiversity Net Gain (BNG) regulations. The approach uses biodiversity units to assess a habitat before development takes place and what is needed to replace any equivalent habitat lost in order to achieve 10% BNG.
The biodiversity metric takes into consideration the size, condition, strategic significance, and type of habitat under consideration. For habitats that are enhanced or newly created, the formula also takes account of the difficulty of creation or enhancement, the time needed, and the distance from the area of habitat loss. It measures all types of habitat, including grassland, hedgerows, lakes, woodland, and watercourses such as rivers or streams.
Follow this link for more information about the statutory (official) biodiversity metric calculation tool
Follow this link for more information about the small sites metric and a detailed user guide are available.
[edit] Biodiversity net gain units
The statutory biodiversity metric measures the biodiversity value of habitats by calculating the number of biodiversity units prior to the development and, thus, what is required to achieve an improvement. There are three types of biodiversity units, which are calculated in three separate modules of the metric covering area units, hedgerow units and watercourse units.
Biodiversity units are the measure to assess a habitat before development takes place, how many units are needed to replace, and those lost through development in order to achieve 10% BNG, according to the regulation. This is achieved through the creation or enhancement of habitats on-site, off-site, or as a last resort through contributions.
A professional ecologist will usually use the available metric tool for a particular project and take on the role of gathering, inputting, and assessing data. Guidance on finding a suitable consultant is published by the Chartered Institute of Ecology and Environmental Management. The statutory (official) biodiversity metric calculation tool must be used in order to demonstrate that a developer has calculated the number of biodiversity units for existing habitat or habitat enhancements in accordance with the agreed statutory biodiversity metric.
[edit] Biodiversity gain plan
A biodiversity gain plan (BGP) is a document that shows how a developer will achieve biodiversity net gain (BNG) according to the BNG planning regulations and law. The biodiversity gain plan can be submitted to the local planning authority after the planning application has been approved. The intention is that a gain plan template will be available for phased developments.
[edit] Biodiversity net gain agreements
Biodiversity net gain agreements are legal agreements to support the obligation to enhance and maintain a habitat. The legal agreement can refer to off-site gains or significant on-site gains and must last for at least 30 years. Net-gain legal agreements are not needed for non-significant on-site enhancements unless they contribute to locally important species or ecological networks. There are two types of legal agreements for BNG: the first is a planning obligation (section 106) with the Local Planning Authority (LPA), and the second is a conservation covenant agreement with a responsible body. Both types of agreements mean the developer of a sub-contracted third party commits to creating or enhancing habitats and managing the habitats for at least 30 years. The legal agreement must be in writing, signed by all parties (‘executed as a deed'), and costs for this are covered by the applicant.
[edit] Local nature recovery strategies or LNRS
Local nature recovery strategies (LNRSs) are 48 areas that cover the whole of England without gaps or overlaps, in which local authorities agree and set priorities for nature recovery and propose actions in certain locations that make a particular contribution to achieving required improvements. The form of the strategy and the type of action will vary according to each area, though each must contain a local habitat map and a written statement of biodiversity priorities to guide the public, private, and voluntary sectors to focus where action is most effective.
[edit] Habitat management and monitoring plan or HMMP
A habitat management and monitoring plan (HMMP) is a detailed plan that outlines how a parcel of land will be managed over at least 30 years to create and enhance habitats for biodiversity net gain as well as monitoring. Such plans are encouraged by the government to capture relevant information for significant on-site enhancements and off-site gains. Planning authorities are also encouraged to set any specific and proportionate monitoring requirements as part of planning conditions and obligations used to secure off-site or significant on-site habitat enhancements.
Natural England published a template to help structure management and monitoring plans and demonstrate how habitat creation, enhancement, management, and monitoring will be undertaken. The template tool can be used for projects of all sizes and for both on-site and off-site units specified by any development project, consenting body, or landowner to provide standardised and consistent management and monitoring information for the project.
[edit] Biodiversity gain site register
The biodiversity gain site register is a national register of land used for biodiversity gains. The Biodiversity Net Gain (BNG) site register will provide a publicly accessible source of information about on- and off-site gains across England. It will record outputs from the BNG metric tool to be completed by a professional ecologist.
Natural England is the operator of the biodiversity gain site register on behalf of Defra. The Register is one part of the BNG services that went live when BNG became mandatory. The service includes a collection of new digital and other services that local planning authorities, developers, landowners, and others will need to be BNG compliant, some of which include: Allocations, where landowners or developers (with permission) can apply to record an allocation of habitat enhancements to their development, Statutory biodiversity credits estimator, where developers can calculate the cost of statutory credits ahead of purchasing them. Statutory biodiversity credit sales scheme where developers can apply to purchase statutory credits.
[edit] Statutory biodiversity credits
Statutory biodiversity credits are proposed as a last resort in the mitigation hierarchy so that, as well as, or instead of, creating and enhancing biodiversity on or off a development site, developers can make a financial contribution that counts towards their mandatory 10% BNG. This contribution is used to fund biodiversity enhancements across England, and the prices are based on the cost to create, maintain, and monitor different habitat types, with a markup to prevent statutory credit prices undercutting the off-site market.
[edit] Nature recovery networks
A national network of wildlife-rich places set aside to increase and restore nature, and the role of the delivery partnership and management group.
[edit] Habitat banks
Habitat banks are parcels of land set aside in order to allow for biodiversity improvement; they are in effect biodiversity banks in the simplest terms, but they also have potential links to financial models through the BNG credit system. There are now a number of financial institutions offering habitat bank investment as part of their service.
[edit] Related articles on Designing Buildings
- Biodiversity in building design and construction
- Biodiversity in the urban environment.
- Biodiversity Gain.
- Biodiversity gain plan.
- Biodiversity gain site.
- Biodiversity gain site register.
- Biodiversity net gain consultation.
- Biodiversity net gain regulations and implementation.
- Biodiversity offsetting.
- Biodiversity units.
- Biodiversity metric.
- Ecological impact assessment.
- Ecology.
- Environmental impact assessment.
- Habitat.
- Habitat management and monitoring plan HMMP.
- Local Nature Recovery Strategy LNRS.
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