Ecology and Biodiversity Net Gain Advice

Ecology & Biodiversity Net Gain - Interim Advice and Information Note - December 2022 Update

From 7^th July 2020, New Forest District Council (NFDC) has sought a minimum of 10% biodiversity net gain as a requirement of planning permission for 'major' new build development.

What type of development is required to provide biodiversity net gain?

The requirement to deliver biodiversity net gain will be applied to all new build development. For 'major' applications the target is to achieve a minimum of 10% biodiversity net gain as a requirement of planning permission to be demonstrated via use of the Natural England Biodiversity Metric.

'Minor' applications, defined as residential development of nine units or less, on a site having an area of less than 1 ha, or all other development types where the site area is less than 0.5 ha, are not exempt from providing biodiversity net gains but use of the Natural England Biodiversity Metric will not normally be required. A beta version of a Small Sites Metric (SSM), a simplified version of Biodiversity Metric 3.1 is available for use - this is not however currently a requirement although NFDC would welcome submissions of the SSM by applicants in support of their minor development proposals.

It should be noted that exceptions on a case-by-case basis may apply e.g. for development at the upper limits of these thresholds where a medium or high impact on biodiversity might be expected or where priority habitats are present within the development area (excluding hedgerows and arable margins). Householder development (such as extensions) falls within the definition of 'minor development'. The requirement for biodiversity net gain does not apply to change of use of an existing building though ecological enhancements are welcomed.

In the interim period before the Government sets the national policy standards and requirements, a pragmatic approach will be taken, ensuring opportunities to maximise biodiversity net gain as part of new development are taken, while not preventing otherwise acceptable development.

Policy background

The Environment Bill received Royal Assent on 9 November 2021, meaning it is now an Act of Parliament. Mandatory biodiversity net gain as set out in the Environment Act applies in England only by amending the Town & Country Planning Act (TCPA) and is expected to become law in 2023.

This interim policy is underpinned by the National Planning Policy Framework (NPPF) paragraph 174(d), which requires planning decisions to provide net gains in biodiversity. Paragraph 179(b) requires plans to identify and pursue opportunities for securing measurable net gains for biodiversity. Paragraph 180(a) suggests that if significant biodiversity losses cannot be avoided, mitigated or compensated then permission should be refused.

New Forest District Council's policy STR1 (iii) in the New Forest District (outside the National Park) Local Plan Review 2016-2036 Part One: Planning Strategy, adopted 6 July 2020 has a requirement for all development to achieve an environmental net gain. 'Environmental Net Gain' encompasses 'Biodiversity Net Gain' and is an approach to development that leaves the natural environment in a measurably better state than it was beforehand.

What is biodiversity net gain and how is it measured?

Biodiversity net gain is an approach to development that leaves biodiversity in a better state than before. Development can produce a biodiversity net gain if it seeks to make its impact on the environment positive, delivering improvements to biodiversity through habitat creation or enhancement after avoiding or mitigating harm.

Where biodiversity net gain is successfully incorporated into the design of a development it can be an asset to the local community as well as to wildlife. Properties near to greenspace often command higher market value than houses further away and encourage healthier lifestyles.

Using a standardised approach, biodiversity net gain will be measured by comparing habitat losses and gains before and after a development has taken place. Where areas of the same site are being utilised for other activities e.g. Alternative Natural Recreational Greenspace (ANRG) / Public Open Space (POS) it will be necessary to demonstrate how the biodiversity net gains are additional to other provisions which would be made irrespective of the biodiversity net gain requirement. (See policy ENV1. of the Local Plan 2016- 2036.)

Biodiversity net gain uses habitat type and quality as a proxy for biodiversity. The Government (Defra/Natural England) have developed a metric which helps to measure biodiversity losses and gains in a more transparent and verifiable way and provides a common reference point for agreement between a developer and a Local Planning Authority.

The metric enables practitioners to calculate the potential biodiversity losses and gains associated with a development proposal by assessing a habitat against four key considerations:

• Type and Distinctiveness: is the habitat of particular ecological importance?
• Condition: is the habitat a good example of its type?
• Extent: what is the extent of the area, in hectares or kilometres (depending on habitat types), that the habitat occupies?
• Strategic Significance: Is the habitat a local priority or located in a priority area for habitat creation/enhancement?

The metric translates this information into biodiversity units. To achieve net gain, a development must have a higher biodiversity unit score after development than before the development. A minimum 10% biodiversity net gain is required for 'habitat units', 'hedgerow units' and where applicable 'river units'.

This guidance now reflects the release of Biodiversity Metric 3.1 and associated guidance. (Previous New Forest District Council guidance required the Beta test toolkit (Biodiversity Metric 2.0) to be used until the final version (3.1) was published). All new projects or those projects where biodiversity net gain calculations are yet to be undertaken should now use Biodiversity Metric 3.1 or the latest published version.

This document does not provide guidance on how to use the biodiversity metric. It is advised that the biodiversity net gain calculations and associated evidence is prepared by a professional, suitably qualified and experienced ecologist. The Natural England website provides guidance on how to use Biodiversity Metric 3.1. available at: http://publications.naturalengland.org.uk/publication/6049804846366720  

Guiding principles

The requirement of biodiversity net gain as part of giving planning permission for development will have a significant impact on the information you need to consider when submitting a planning application. The 'Guiding Principles' for biodiversity net gain and submissions in general are set out in Table 1 below.

Table 1: Guiding Principles

Table 2: Guideline Survey Timetable

What ecological information is required to support a planning application?

The information you will need to submit with your planning application will vary by site and scale of development. Guidance is provided as to whether a Preliminary Ecological Appraisal (PEA) or Ecological Impact Assessment (EcIA) is appropriate to support an application.

• Biodiversity Checklists - A biodiversity checklist is to be completed for ALL applications. There is a separate checklist for Full applications and Householder applications. These are provided in Appendix A and Appendix B of this advice note respectively. If further ecological considerations are shown to be required, then a PEA or EcIA (supported by appropriate survey effort) should be submitted to support the application (noting the comment in bold below).
• Preliminary Ecological Appraisal (PEA) - PEAs provide an initial assessment of any ecological constraints and opportunities relevant to a proposed development and consist of a desktop study and a site survey to identify and map features of ecological value. Guidelines for Preliminary Ecological Appraisal are published by the Chartered Institute of Ecology and Environmental Management (CIEEM)3. Where the PEA process identifies potential ecological constraints (such as the presence of protected species), further surveys and assessment are likely to be necessary. The PEA will usually contain some initial recommendations as to how the potential ecological impacts of a proposal might be avoided or mitigated, and where biodiversity enhancements could be delivered. A PEA is not a substitute for Ecological Impact Assessment (EcIA) described below and are not suitable to support a planning application unless no significant ecological constraints have been identified.
• Ecological Impact Assessment (EcIA) - For development where potentially significant ecological effects are likely to arise from proposals, an EcIA will be required. Typically, the EcIA report prepared for planning submission will collate the baseline information gathered during the PEA and/or other detailed surveys. It will value existing ecological features, consider the potential effects of development and assess any residual ecological impacts after mitigation (both adverse and beneficial). In addition to any mitigation required, ecological enhancements to be provided should be set out in detail. The Guidelines for Ecological Impact Assessment published by CIEEM in 2018 (updated 2019) should be adhered to.

Delivering biodiversity net gain ('major applications')

For 'major' applications the planning application should also be supported by Natural England Biodiversity Metric calculations, details are provided below:

• Natural England Metric Net Gain Calculations (Biodiversity Report)
  • Baseline - Should include full details of the ecological baseline including detailed justifications for the choice of habitat types (Using UKHabs Classification System (Phase 1 habitats can be translated into the new system using online resources)), distinctiveness and condition. Condition sheets should be submitted for each habitat type where applicable. An interim score of Fairly Poor or Fairly Good should only be used in special circumstances where a habitat does not fit the standard outcome of Good, Moderate or Poor. Justification for allocating an interim condition score must be provided within the condition assessment proforma and within the Biodiversity Metric 3.1 tool assessors comments. Any assumptions made should be presented and likewise justified. A plan should clearly illustrate the areas covered by each of the existing habitat types and the area/length in hectares/km of each habitat type.
  • Proposed - A proposed habitats plan, for example taken from the site layout plan, illustrative masterplan, green infrastructure plan or landscape plan should also be included. The plan should detail what existing habitats are to be retained and enhanced, and any new habitat types that will be created. The plan should ensure that each habitat type is identified, and the area/length of each habitat type should be quantified in hectares/km. In line with changes made in 3.1 this should instead comprise 'urban vegetated gardens' and 'urban developed land sealed surface'. A standard split of 70/30 developed land / garden should be used.
  • Reporting - The report should demonstrate how each of the BNG good practice principles have been applied and the mitigation hierarchy adhered to. A copy of the Metric (i.e. the completed spreadsheet) should be submitted. A summary is not sufficient and will not be accepted. The information in the metric should correspond directly to the Biodiversity Report and the Proposed Habitats Plan. An example BNG design stage report template is provided in CIEEM's publication 'Biodiversity Net Gain Report & Audit Templates' Guidance.

• Additionality - Where areas of the same site are being utilised for other activities e.g. ANRG, it will be necessary to demonstrate how the biodiversity net gains are additional to other provisions which would be made irrespective of the biodiversity net gain requirement. Natural England and Defra are currently looking at 'additionality' or 'stacking' and a position is expected to be set out in the forthcoming Defra consultation on BNG secondary legislation. The current position is that it is possible to use sites delivering other mitigation to also deliver BNG, on the basis that:
  • Delivery of the non-BNG outcomes via habitat creation/enhancement could contribute up to a point equivalent to no net loss of BNG but not beyond.
  • To achieve the required biodiversity unit uplift beyond no net loss (and into net gain) to meet the BNG requirement, there must be habitat provision, additional habitat features or enhancement beyond the minimum requirements of other non-BNG provisions e.g. ANRG.
  • Good practice would be to illustrate BNG contributions derived from incidental non-BNG mitigation and specific BNG measures using a separate accounting line for each source in the interests of transparency

Examples of how this has been addressed on other applications can be provided, discussed and you are encouraged to liaise with the NFDC Ecologist to agree an appropriate way of addressing additionality in the absence of a wider agreed approach for practitioners.

• Further enhancements - Whilst other ecological enhancements, not related to habitats do not get factored into the biodiversity metric, these should still be provided and can be included within the Biodiversity Report. Such measures could include bird boxes, bat boxes, gaps in close board fences for hedgehogs, invertebrate bricks e.g. bee bricks, hibernacula and deadwood features. It is the expectation of NFDC that one built in enhancement feature be provided per dwelling (from bird nesting, bat roosting or bee brick) - some dwellings may have more than one feature, others may not have any and the most suitable locations should be identified by the project ecologist.
• BNG Implementation and Delivery - Details should be provided for how the masterplan or design concept will be delivered. This should include drawings, for example detailed landscape planting schedules, management proposals and/or a construction handover checklist or timetable.
• Management and Monitoring - A Biodiversity Monitoring and Management Plan (MMP) will be critical to the successful delivery and long-term (covering a minimum 30 years) provision of BNG. The BNG MMP should provide detailed management and maintenance information for years 1-5 and broader management aims for the lifetime of the BNG commitment and be updated at appropriate intervals with sufficient detail. It will be necessary to secure the long-term management and monitoring of BNG through any planning permission. Monitoring should utilise the same version of the metric as was utilised within the planning application. In outline, the monitoring and management plan should include:
  • Methods for delivering BNG;
  • Roles, responsibilities and competency requirements for delivering BNG - during and after construction;
  • Detail legal, financial and other resource requirements for delivery of BNG;
  • Description of the habitats to be managed;
  • Ecological trends and constraints on site that might influence management;
  • Clear timed and measurable 'SMART' objectives in the short, medium and long-term for BNG - Detail objectives for all habitats (target condition) and define key indicators to measure success;
  • Define appropriate management options and actions for achieving aims and objectives;
  • A commitment to adaptive management in response to monitoring to secure the intended biodiversity outcomes;
  • Preparation of a work schedule;
  • Details for a formal review process when objectives are not fully reached;
  • Key milestones for reviewing the monitoring;
  • Establish a standard format for collection of monitoring data to make it repeatable and consistent including methods, frequency and timing. The number of monitoring assessments required will depend on the habitat type and extent, but a typical schedule for a medium sized habitat creation project might require surveys and reports preparing for years 2, 5, 10, 20 and 30;
  • Identify and define set monitoring points (representing the key habitats on site) where photographs can be taken as part of monitoring to record the status of habitats on site; and
  • Detail reporting procedures.

The measures to deliver biodiversity net gain will normally be agreed prior to the issue of a planning permission. Planning conditions or a legal agreement will be used to ensure the agreed measures are implemented and maintained for a period of no less than 30 years after the development is completed.

'Major' outline applications still require Natural England Metric Net Gain calculations to be undertaken. These should be based on the best available information, for example a parameters plan or illustrative masterplan. Any assumptions made should be clearly defined and quantified. This will enable a judgement to be made as to whether or not the application is likely capable of meeting the minimum 10% net gain requirement. The calculations will be required to be re-run at reserved matters stage to ensure that the predicted gains remain deliverable following detailed design unless no significant changes to the original design are proposed. The re-run calculations should utilise the same version of the metric as was utilised within the outline planning application for consistency.

What happens if the metric shows a net loss or under 10% net gain?

In the event that the biodiversity metric indicates that there will be a net loss of biodiversity or a shortfall (minimum 10% required), NFDC will require compensation for the losses and seek an overall net gain (>10%) in biodiversity through consideration of the following options:

a) Review and update the proposed development to avoid a biodiversity net loss and to demonstrate the achievement of 10% biodiversity net gain;

b) Securing appropriate compensation for habitat loss, sufficient to deliver the required level of biodiversity net gain, off site on land owned or controlled by the applicant/site owner. This would be considered on a case by case basis and only if use of the mitigation hierarchy has been demonstrated, and the site proposed is considered suitable, appropriate (e.g. geographically) and satisfies trading rules, for example there should be no trading down in habitat distinctiveness. All high distinctiveness habitats require re-creation on a like-for-like basis should they be lost, whereas there is more flexibility for lower distinctiveness habitat types in terms of what habitat can be delivered if they are lost (See Table 6-1 in the User Guide).The offset site would need to be subject to ecological surveys to prove that the land is appropriate for use and assessment using the metric to show the site can deliver the required number of biodiversity units to achieve a net gain overall. The offset site would then be legally linked to the application through a planning obligation in a Section 106 (S106) agreement; or

c) Developer enters into an agreement with a delivery provider (a third-party organisation such as a Habitat Bank who will create and manage habitats) for off-site BNG (e.g. to achieve the expected target of 10%) to be agreed by NFDC.

Please also get in touch if you are a landowner within the District who may be interested in becoming an offset biodiversity provider  E-mail: planning@nfdc.gov.uk

Demonstrating biodiversity net gain on small sites ('minor applications')

This section gives guidance on measures which can be incorporated into small developments to assist in delivering biodiversity net gain, demonstrating compliance with the National Planning Policy Framework and local Development Plan policies.

Small scale, 'minor' new developments are not exempt from the requirement to deliver biodiversity net gain as part of development, however, completion of the full Biodiversity Metric is not required for these applications under this interim guidance. A simplified version of the Biodiversity Metric 3.1 referred to as the 'Small Sites Metric (SSM)' has been published. It has been specifically designed for use on small development sites. It is currently in a Beta test format. NFDC would welcome submission of the SSM to support applications but to do so is at the discretion of the applicant currently. Where the Small Sites Metric is not used, in proportion to the scale of the development, 'minor' developments can still deliver features that will be valuable to wildlife and enhance local biodiversity. This is not an exhaustive list but is intended to provide guidance as to the types of features which are sought to be incorporated into applications. The most suitable and locally appropriate enhancement measures will vary depending on the location and type of development. For enhancements incorporated into a building these should be shown on the appropriate drawings e.g. elevation drawings and will form part of the approved application.

Habitats

• Incorporate native species planting or planting with demonstrable wildlife value;
• Create a pond (Link to Froglife Guidance here);
• Retain and create deadwood habitats e.g. log piles;
• Plant trees including fruit trees such as cherry, apple and pear and those with early spring blossom such as hawthorn and blackthorn;
• Plant species given in the Royal Horticultural Societies (RHS) "Perfect for Pollinators" list, preference being given to native species;
• Create biodiverse roofs on new buildings where structurally viable or incorporate green walls with climbing plants e.g. honeysuckle;
• Incorporate native species rich hedgerows in preference to close board fencing where appropriate, species could include; blackthorn, beech, hawthorn, hornbeam, dog rose, field maple, holly, hazel and wild privet; and
• Create areas of native wildflower 'meadow' planting or incorporate wildflowers which grow well in lawns such as lady's bedstraw, rough hawkbit, oxeye daisy, bird's-foot-trefoil, cowslip, selfheal, meadow buttercup and red clover.

Species

Target species	Within landscaped areas	Within building fabric / building mounted
Birds	Establish native planting particularly berry and seed producing trees and shrubs Provision of tree / wall mounted bird nest boxes e.g. Schwegler 1B (or similar)	Incorporation of bird nesting features into the building fabric, for example for swifts. Swift boxes have been shown to also be used by the red-listed house sparrow and starling and are the favoured option. Swift bricks/boxes should be installed under an overhang or under the eaves or on walls facing north, northeast or north-west out of direct sunlight to give it protection from weather and heat. It should be sited at least 5 metres above ground, with clear adjacent airspace (a similar amount of clear drop below them) so the Swifts can access it in high-speed direct flight. They should not be placed directly above windows and doors. The specification, number and location of the boxes should be shown on a plan and relevant elevation drawings.
Bats	Bat friendly planting (BCT Guidance here) Provision of bat boxes (Schwegler type or similar - made from woodcrete for longevity) at a minimum height of 3m in an open sunny position.	Incorporate bat roosting features into the building fabric e.g. bat boxes at least 4-5m above the ground, close to hedge and tree lines, sheltered from strong winds and exposed to sun for part of the day (usually S/SW).
Hedgehog	Consider post and rail fencing and/or hedgerow planting in place of close board fencing. Where close board fencing is required provide hedgehog gaps (13cmx13cm) in gravel boards.
Invertebrates	Create biodiverse roofs on new buildings Create mosaic of scrub, hedges, grassland Create pond(s) with shallow sides Retain and create deadwood habitats Plant trees with early spring blossom such as hawthorn, blackthorn and willow Create 'insect hotels' Plant species given in the Royal Horticultural Societies (RHS) "Perfect for Pollinators" list	Provide bee bricks built into building fabric. These should be located on a south facing elevation, in a warm sunny spot. They need to be placed at least 1 metre from ground level with no upward height limit.

Further reading and advice:

Natural England Biodiversity Metric 3.1: The Biodiversity Metric 3.1 - JP039 (nepubprod.appspot.com)

Natural England The Small Sites Metric (JP040):The Small Sites Metric - JP040 (naturalengland.org.uk)

CIEEM Biodiversity Net Gain - Good Practice Principles for Development:  https://cieem.net/wp-content/uploads/2019/02/C776a-Biodiversity-net-gain.-Good-practice-principles-for-development.-A-practical-guide-web.pdf

CIEEM EcIA Guidelines: https://cieem.net/resource/guidelines-for-ecological-impact-assessment-ecia/

CIEEM /ALGE EcIA Checklist: https://cieem.net/resource/ecological-impact-assessment-ecia-checklist/

CIEEM PEA Guidelines: https://cieem.net/resource/guidance-on-preliminary-ecological-appraisal-gpea/

CIEEM Biodiversity Net Gain Report and Audit Templates: Biodiversity Net Gain Report and Audit Templates | CIEEM

Standing advice for protected species:

• bats, all species
• great crested newts
• badgers
• hazel or common dormice
• water voles
• otters
• wild birds
• reptiles
• protected plants
• white-clawed crayfish
• invertebrates
• freshwater fish
• natterjack toads
• ancient woodland and veteran trees

Appendix A: Biodiversity Checklist (Full application)

Appendix B Biodiversity checklist (householder application)