Discover our glossary

The accessibility to and within the site, for vehicles, cycles, and pedestrians in terms of the positioning and treatment of access and circulation routes and how these fit into the surrounding access network.

An approach which allows mitigation measures to be adjusted in response to greater certainty on effects following implementation. Also known as Dynamic Mitigation or Adaptive Planning.

A real increase in social value that would not have occurred in the absence of the intervention being appraised

Any area that has been wooded continuously since at least 1600 AD, including:Ancient Semi-Natural Woodlands (ASNW); and Plantations on Ancient Woodland Sites (PAWS) Ancient Woodland sites are listed on the Ancient Woodland Inventory Database. If the woodland is less than 2ha, it needs to be checked against the criteria set out in the Ancient Woodland Inventory Handbook for features that indicate whether it may be ancient.

The aspects of a building or place within the development which determines the visual impression the building or place makes, including the external built form of the development, its architecture, materials, decoration, lighting, colour, and texture.

Habitats recorded in the biodiversity metric tool in area (hectares).

The competent person completing the Biodiversity Metric. See also Competent Person.

Prevention of impacts occurring, having regard to predictions about potentially negative environmental effects (eg project decisions about site location or design)

A description of existing conditions to provide a starting point (eg pre-project condition of biodiversity) against which comparisons can be made (eg post- impact condition of biodiversity), allowing the change to be quantified

The variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems.

Documents that were produced after the Convention on Biological Diversity at Rio de Janeiro in 1992. This stated that each country has the primary responsibility to save and enhance biodiversity, and the signatories agreed to draw up national plans and programmes and to share resources to help implement them.

The pre-development biodiversity value of the onsite habitatSource:

Created under section 101 of the Environment Act 2021. Can only be used to offset biodiversity losses if it is not possible to secure gains onsite or via offsite units.

Document which is required to comply with schedule 14 of the Environment Act 2021.

Tool used to measure biodiversity loss and gain in a consistent and robust way by using surrogate or proxy measures, which represent biodiversity. Created via schedule 14 of the Environment Act 2021.

Development that leaves biodiversity in a better state than before. An approach where developers work with local governments, wildlife groups, land owners and other stakeholders to support their priorities for nature conservation.

Habitats recorded in the SSM in length (m). Three watercourse habitats are available.Source: Biodiversity Small Site Metric User Guide (Draft)

Produced by the Biodiversity Metric. The metric calculates the values as ‘biodiversity units’. Biodiversity units are calculated using the size of the habitat, its quality and location and are used to describe relative biodiversity value. There are three types of biodiversity units: area habitat units, hedgerow units and watercourse units. Each of these are calculated in separate ‘modules’ of the biodiversity metric.

Land which is or was occupied by a permanent structure including the curtilage of the developed land (although it should not be assumed that the whole of the curtilage should be developed) and any associated fixed surface infrastructure. This excludes: land that is or was last occupied by agricultural or forestry buildings; land that has been developed for minerals extraction or waste disposal by landfill, where provision for restoration has been made through development management procedures; land in built-up areas such as residential gardens, parks, recreation grounds and allotments; and land that was previously developed but where the remains of the permanent structure or fixed surface structure have blended into the landscape.

See Special Area of Conservation (SAC)

Where there is a change in the purposes for which or the circumstances in which a building is used, so that after that change—

(a) the building is used as a dwelling, where previously it was not;

(b) the building contains a flat, where previously it did not;

(c) the building is used as an hotel or a boarding house, where previously it was not;

(d) the building is used as an institution, where previously it was not;

(e)the building is used as a public building, where previously it was not;

(f) the building is not a building described in classes 1 to 6 in Schedule 2, where previously it was;

(g) the building, which contains at least one dwelling, contains a greater or lesser number of dwellings than it did previously;

(h) the building contains a room for residential purposes, where previously it did not;

(i) the building, which contains at least one room for residential purposes, contains a greater or lesser number of such rooms than it did previously; or

(j) the building is used as a shop, where previously it was not.

Someone who has the knowledge and skills to perform specified tasks to complete and review the Biodiversity Metric. Will usually need to be a Suitably Qualified Ecologist. Someone can become a competent person through training, qualifications, experience, or a combination of them.

Someone who has the knowledge and skills to perform specified tasks to complete and review Small Site Metric (SSM) calculations. This can be obtained through training, qualifications, experience, or a combination of them. A competent person completing the SSM is known as the SSM ‘user’.

A measure of the habitat against its ecological optimum state. Condition is a way of measuring variation in the quality of patches of the same habitat type. You should conduct a condition assessment for all habitat parcels which require you to assign a condition to them in the biodiversity metric tool. You should use the biodiversity metric condition sheets to do this and provide these as evidence to support your assessment.Biodiversity metric condition sheets can be used to evidence good, moderate or poor condition. Fairly good and fairly poor are intermediate condition categories. If you need to use these, you should complete a biodiversity metric condition assessment sheet; make site specific judgements using ecological expertise; explain any deviations against specific condition criterion; provide ecological reasoning. You should not use the intermediate categories beyond a one-step adjustment from a standard condition sheet result (for example, from ‘moderate’ condition up to ‘fairly good’, or down to ‘fairly poor’) and they should not be used for the post-developSource:

The process of assigning habitat condition, to be undertaken by a competent person.

A measure of the functional availability of the habitats needed for a particular species to move through a given area. Examples include the flight lines used by bats to travel between roosts and foraging areas or the corridors of appropriate habitat needed by some slow-colonising species if they are to spread.

The condition is that any habitat enhancement will, by virtue of (a) a condition subject to which the planning permission is granted;(b) a planning obligation, or (c)a conservation covenant,be maintained for at least 30 years after the development is completed.

A parcel of land managed for its conservation values. In exchange for permanently protecting the land, the bank owner is allowed to sell credits to parties who need them to satisfy legal requirements for compensating environmental impacts of development

Any land that, in the opinion of the local authority in whose area it is located, is in a condition due to substances in, on, or under the land, where: (a) Significant harm is occurring or there is a significant likelihood of such harm occurring; or (b) Significant pollution of controlled waters is occurring or there is a significant likelihood of such pollution occurring.

Defined by the Flood and Water Management Act 2010. A covered channel or pipe designed to prevent the obstruction of a watercourse or drainage path by an artificial construction. Culverted sections of any watercourse type should be recorded as ‘culvert’.

Additional changes caused by a proposed development along with other developments or the combined effect of a set of developments taken together. In ecological terms cumulative effects may derive from a combination of effects from a development project with other past, present or reasonably foreseeable future projects. They may also result from time- or space-crowding of development combined with the effects of stochastic events/changes, including climate change. Cumulative impacts is the total arising from the project (under the control of the developer), other activities (that may be under the control of others, including developers, local communities, government) and other background pressures and trends that may be unregulated. The project’s impact is one part of the total cumulative impact on the environment. The analysis of a project’s incremental impacts combined with the effects of other projects can often give a more accurate understanding of the likely results of the project’s presence than considering its impacts in isolation

The carrying out of building, engineering, mining or other operations in, on, over or under land, or the making of any material change in the use of any buildings or other land.

A measure which represents the uncertainty in the effectiveness of management techniques used to enhance or create habitat.

A measure based on the type of habitat and its distinguishing features. This includes consideration of species richness, rarity, the extent to which the habitat is protected by designations and the degree to which a habitat supports species rarely found in other habitats.

Does not include a building containing one or more flats, or a flat contained within such a building.

An application for planning permission for EIA development; or a subsequent application in respect of EIA development

A development which is either a—

(a) Schedule 1 development; or

(b) Schedule 2 development likely to have significant effects on the environment by virtue of factors such as its nature, size or location

Species that occupy similar niches in different geographical regions. In the context of biodiversity offsets, the term is synonymous with the concept of ‘like-for-like’ and refers to areas with highly comparable biodiversity components. This similarity can be observed in terms of species diversity, functional diversity and composition, ecological integrity or condition, landscape context (eg connectivity, landscape position, nearby land uses or condition, patch size), and ecosystem services (including people’s use and cultural values)

Habitats, species or ecosystems.

An interconnected system of ecological corridors

An individual who: Holds a degree or equivalent qualification (e.g. N/SVQ Level 5) in ecology or a related subject Is a practising ecologist, with a minimum of three years’ relevant experience (within the last five years). Such experience must clearly demonstrate a practical understanding of factors affecting ecology in relation to construction and the built environment, including acting in an advisory capacity to provide recommendations for ecological protection, enhancement and mitigation measures. Examples of relevant experience are ecological impact assessments, Phase 1 and 2 habitat surveys, and habitat restoration Is covered by a professional code of conduct and subject to peer review.

A dynamic complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit

Services provided by the natural environment that benefit people.

Improved management of ecological features or provision of new ecological features, resulting in a net benefit to biodiversity, which is unrelated to a negative impact or is ‘over and above’ that required to mitigate/compensate for an impact.

Inland waters, except groundwater; transitional waters and coastal waters, except in respect of chemical status for which it shall also include territorial waters.Source: Environment Act 2021

The Environmental Statement including any further information and any other information, any representations made by any body required by the Town and Country Planning (Environmental Impact Assessment) Regulations 2011 to be invited to make representations, and any representations duly made by any other person about the environmental effects of the development.

There are new environmental land management schemes will help achieve thriving plants and wildlife by paying for measures such as habitat creation and restoration as well as species management actions. The environmental land management schemes will work alongside mandatory biodiversity net gain as another source of income to enhance biodiversity and the wider environment.

An approach to development that leaves the natural environment in a measurably better state than it was beforehand. It was set out as a vision in the UK Government’s 25 Year Environment Plan, and biodiversity net gain is the first step to achieving it. Environmental net gain means building on biodiversity net gain and going further to achieve increases in the capacity of affected natural capital to deliver ecosystem services and make a scheme’s wider impacts on natural capital positive.

Tools such as the The Environmental Benefits from Nature Tool (EBNT) (formerly the EcoMetric) which can be used alongside biodiversity metric, and will enable some of these wider natural capital impacts of development to be understood. The EBNT may be used when delivering biodiversity net gain to facilitate better design.

A statement that includes the following information: 

Description of the development, including in particular—

(a)a description of the physical characteristics of the whole development and the land-use requirements during the construction and operational phases;

(b)a description of the main characteristics of the production processes, for instance, nature and quantity of the materials used;

(c)an estimate, by type and quantity, of expected residues and emissions (water, air and soil pollution, noise, vibration, light, heat, radiation, etc) resulting from the operation of the proposed development.

An outline of the main alternatives studied by the applicant or appellant and an indication of the main reasons for the choice made, taking into account the environmental effects.

A description of the aspects of the environment likely to be significantly affected by the development, including, in particular, population, fauna, flora, soil, water, air, climatic factors, material assets, including the architectural and archaeological heritage, landscape and the inter-relationship between the above factors.

A description of the likely significant effects of the development on the environment, which should cover the direct effects and any indirect, secondary, cumulative, short, medium and long-term, permanent and temporary, positive and negative effects of the development, resulting from

(a)the existence of the development;

(b)the use of natural resources;

(c)the emission of pollutants, the creation of nuisances and the elimination of waste,

and the description by the applicant or appellant of the forecasting methods used to assess the effects on the environment.

A description of the measures envisaged to prevent, reduce and where possible offset any significant adverse effects on the environment.

A non-technical summary of the information provided [under the above]

An indication of any difficulties (technical deficiencies or lack of know-how) encountered by the applicant or appellant in compiling the required information.

It should be the information that is reasonably required to assess the environmental effects of the development and which the applicant can, having regard in particular to current knowledge and methods of assessment, reasonably be required to compile, but that includes at least the following: 

A description of the development comprising information on the site, design and size of the development.

A description of the measures envisaged in order to avoid, reduce and, if possible, remedy significant adverse effects.

The data required to identify and assess the main effects which the development is likely to have on the environment.

An outline of the main alternatives studied by the applicant or appellant and an indication of the main reasons for the choice made, taking into account the environmental effects.

A non-technical summary of the information provided [under the above]

A term that was established during Brexit to describe sites that, previously defined and protected under EU law, would instead have their status enshrined in UK law. Defined by Regulation 8 of the Conservation of Habitats and Species Regulations 2017, European Sites include:

• Special Areas of Conservation
• Sites of Community Importance which has been placed on the list referred to in the third sub-paragraph of Article 4(2) of the Habitats Directive (list of sites of Community importance)
• a site hosting a priority natural habitat type or priority species protected in accordance with Article 5(4) of the Habitats Directive
• an area classified pursuant to Article 4(1) or (2) of the old Wild Birds Directive or the new Wild Birds Directive
• Sites set out in accordance with Article 4(1) of the Habitats Directive before the UK left the EU (link)

The Secretary of State must keep a list of all European Sites.