CIVITY NGE Blog

Biodiversity Net Gain does not end when biodiversity units are allocated or planning permission is secured. For significant on-site gains and off-site provision, long-term habitat management and monitoring are fundamental to demonstrating that promised biodiversity improvements are actually being delivered. Under England’s statutory biodiversity net gain (BNG) framework, qualifying habitat enhancements must generally be secured for at least 30 years. The relevant legal agreement must establish responsibilities for creating or enhancing habitats and for their ongoing management, maintenance and monitoring. For developers, land managers, private landowners and habitat bank providers, this makes BNG monitoring and reporting an important long-term obligation. Monitoring provides evidence that habitat creation and habitat enhancement are progressing towards the target condition used to calculate biodiversity units in the statutory biodiversity metric. This guide explains who is responsible for BNG monitoring, what evidence should be collected, how reporting intervals work and how monitoring integrates with a Habitat Management and Monitoring Plan (HMMP). What Is BNG Monitoring and Reporting? BNG monitoring is the process of assessing whether habitats created, retained or enhanced as part of a biodiversity gain commitment are progressing towards their agreed ecological objectives. Reporting turns those findings into documented evidence that can be reviewed by the relevant local planning authority (LPA) or responsible body. The exact monitoring requirements depend on the habitat type, legal agreement and HMMP. Monitoring may involve ecological surveys, habitat condition assessments, fixed-point photography, mapping, records of habitat management and evidence of remedial works. The purpose is not simply to demonstrate that habitat still exists. Monitoring should show whether it is developing towards the condition and biodiversity value upon which the original biodiversity metric calculation was based. For example, where species-rich grassland has been created, monitoring should assess whether the habitat is developing towards its intended condition rather than simply recording that grassland remains present. Why Long-Term Monitoring Is Required Biodiversity gains are based on predicted future habitat outcomes. When the statutory biodiversity metric calculates the value of proposed habitat creation or enhancement, the resulting biodiversity units can depend on assumptions about the condition that habitat will achieve over time. Creating habitats therefore does not automatically mean the predicted ecological value has been delivered. Long-term monitoring provides the evidence needed to assess progress. It can identify whether habitat management is working, whether undesirable species are becoming established and whether intervention is needed to keep the habitat on its intended trajectory. This is particularly important for off-site biodiversity units, because those units may have been allocated to development projects on the basis of biodiversity improvements that need to remain secure for decades. Government guidance requires legal agreements securing relevant BNG habitat enhancements to specify responsibility for habitat creation or enhancement and subsequent maintenance, management and monitoring. The 30-Year Statutory Monitoring Period Explained The Environment Act framework establishes long-term requirements for biodiversity net gain. Significant on-site enhancements and off-site gains must generally be maintained for at least 30 years. For off-site gains, the legal agreement must last for at least 30 years from completion of the habitat enhancement works. The same minimum period applies where significant on-site gains are legally secured. This distinction matters because the management period does not simply begin when a developer purchases off-site units or when planning permission is granted. The legal agreement, HMMP and associated documentation should establish when the relevant period begins and how habitat delivery will be monitored throughout it. Thirty years is a minimum statutory period rather than an indication that habitat should cease to be valuable afterwards. Well-designed habitat banks can contribute to longer-term nature recovery, ecological networks, ecosystem services and priorities identified through a Local Nature Recovery Strategy. For landowners considering whether to sell biodiversity units, this long-term commitment should be considered alongside financial viability, legal costs, land management requirements and any interaction with Countryside Stewardship or other agri-environment schemes. Who Is Responsible? Developers, Landowners, Habitat Banks and LPAs Responsibility for BNG monitoring depends on where the biodiversity gain is being delivered and how it has been legally secured. Developers For on-site gains, developers may retain responsibility for ensuring significant habitat enhancements are delivered and managed, depending on the arrangements established through the Biodiversity Gain Plan and associated legal mechanisms. Where developers buy off-site units from a separate landowner or habitat bank, the landowner’s legal agreement can secure the off-site gain. Government guidance confirms that a developer does not need to enter a separate legal agreement for that off-site land where the gain has already been secured by the landowner. This is one of the advantages of purchasing units from established, high-quality habitat banks: responsibility for delivering and managing the off-site habitat can be clearly established through the provider’s existing arrangements. Landowners and Land Managers For off-site BNG, the landowner or qualifying leaseholder enters into the relevant legal agreement and commits to creating or enhancing and managing the habitats. The agreement should identify who is responsible for maintenance, monitoring and reporting. The landowner may undertake aspects of the work directly or appoint suitably qualified land managers and ecological consultants. Anyone planning to register land and generate biodiversity units should therefore understand that selling units involves ongoing management obligations rather than a one-off land transaction. Habitat Bank Providers A habitat bank provider may coordinate habitat creation, ongoing management, ecological monitoring and reporting across the gain site, depending on the ownership and contractual structure. This can include coordinating ecological expertise, maintaining records, monitoring habitat units and demonstrating progress against the HMMP. The site’s legal arrangements remain crucial. A habitat bank must have the appropriate long-term legal security before its off-site gains can be used within the statutory BNG system. Local Planning Authorities and Responsible Bodies Where off-site gains are secured through a Section 106 planning obligation, the LPA is responsible for monitoring the agreement and can take enforcement action if obligations are not met. Where a conservation covenant is used instead, the relevant responsible body performs the corresponding monitoring and enforcement role. The agreement should establish how monitoring will take place, how the land can be accessed and what happens if habitat enhancement does not progress as intended. What Evidence Needs to Be Collected? Evidence should correspond to the habitat objectives, monitoring methodology, legal agreement and HMMP. A strong evidence record will commonly include dated habitat surveys and condition assessments showing how habitats are progressing against their targets. Fixed-point photographs can provide a consistent visual record, while maps and GIS information can demonstrate the location and extent of the habitats being monitored. Records of management activities are equally important. These might document cutting or grazing regimes, establishment works, invasive species control, planting, water management or other interventions relevant to the habitat. Where monitoring identifies underperformance, reports should document the issue, explain its likely cause and record the remedial management being undertaken. The original baseline surveys, statutory biodiversity metric calculation and agreed habitat objectives provide the reference point against which progress can be assessed. Government guidance for HMMPs specifically expects information about planned management, when and how monitoring will occur, when results will be reported, how management proposals will be reviewed and how biodiversity value will be restored if the site fails to achieve its target condition. BNG Reporting Intervals and Compliance Requirements There is an important distinction between the 30-year management requirement and the frequency of reporting. BNG does not impose one universal annual reporting timetable for every site. Monitoring and reporting intervals should be established within the HMMP and legal agreement and agreed with the LPA or responsible body. Different habitat types may require different frequencies, particularly during establishment. Newly created habitats may need closer attention in their early years, while monitoring can change as habitats become established. An HMMP should therefore state clearly when ecological monitoring will occur, when reports will be submitted and when the management strategy will be formally reviewed. Where annual monitoring is appropriate, reports should be structured consistently so progress can be compared over time. However, developers and landowners should follow the specific reporting schedule secured for their site rather than assuming an annual report is always legally required. For off-site BNG, the legal agreement should also establish access arrangements, monitoring schedules, funding arrangements and what action will be taken if habitat enhancement does not proceed as intended. How Monitoring Links to Habitat Management and Monitoring Plans (HMMPs) The Habitat Management and Monitoring Plan is the practical framework connecting habitat objectives with long-term delivery. An HMMP does not replace the legal agreement. Instead, it provides the detail needed to explain how the habitat will be created, enhanced, managed, monitored and, where necessary, corrected over time. The HMMP will be referenced extensively within the legal agreement and is likely to be appended to it as a key supporting document. For off-site gains, the HMMP should be agreed with the LPA where the land is secured through a Section 106 planning obligation or with the responsible body where a conservation covenant is used. The plan should establish the intended habitat outcomes, management actions, monitoring methodology, reporting schedule and responsibilities throughout the management period. For example, an HMMP covering species-rich grassland might specify establishment methods, cutting or grazing regimes, control of undesirable species, target habitat condition, monitoring methodology and remedial measures if the grassland does not develop as anticipated. This creates a direct relationship between the ecological assumptions used to calculate site biodiversity units and the practical management needed to deliver them. Common BNG Monitoring Mistakes One of the biggest mistakes is treating monitoring as something that can be designed after the habitat has already been created. Monitoring requirements should be considered alongside habitat creation and management planning so that suitable baseline evidence and repeatable methodologies are available from the outset. Another problem is collecting evidence inconsistently. Photographs taken from different locations, ecological surveys using incompatible methods or incomplete management records make it harder to demonstrate long-term trends. A further risk is documenting problems without adapting management. Monitoring should inform action. If a habitat is failing to reach its target condition, the management strategy should respond and the remedial measures should be recorded. Finally, developers and landowners should avoid assuming that registration on the Biodiversity Gain Site Register replaces long-term monitoring. Registration establishes information about the gain site and allocated habitats, while the legal agreement and HMMP govern the long-term delivery and management obligations. Natural England’s register records information including gain-site location, habitat creation or enhancement and allocations to developments. BNG Monitoring Checklist Use this practical checklist alongside the site’s legal agreement and HMMP rather than as a substitute for professional ecological advice. Confirm the baseline habitats, biodiversity value and statutory biodiversity metric calculation. Identify every habitat type, target condition and associated biodiversity units. Confirm who is responsible for habitat creation, enhancement, management, monitoring and reporting. Check the Section 106 planning obligation or conservation covenant and its management obligations. Confirm the start and end dates of the minimum 30-year management period. Agree monitoring and reporting intervals with the LPA or responsible body. Establish repeatable habitat survey and condition-assessment methods. Create fixed photographic monitoring points. Maintain dated records of habitat management activities. Record changes in habitat condition and ecological value. Document problems, corrective actions and subsequent outcomes. Compare monitoring results against HMMP objectives and target conditions. Retain copies of ecological surveys, photographs, maps and management records. Review the management plan at the intervals established within the HMMP. Keep responsibilities and contact details current if ownership or management arrangements change. How Civity Supports Long-Term BNG Monitoring and Reporting At Civity, our role is focused on the delivery and management of the off-site biodiversity gains provided through our habitat banks rather than providing developers with standalone ecological surveys or pre-planning biodiversity assessments. For developers purchasing Civity’s off-site BNG units, the long-term habitat delivery associated with those units sits within the legally secured gain-site arrangements. This provides a clear distinction between the developer’s development site and the off-site provision being delivered through the habitat bank. For landowners working with Civity, long-term BNG delivery means establishing clear management obligations from the outset, documenting habitat enhancement and maintaining the evidence required throughout the management period. The legal agreement, statutory biodiversity metric and HMMP provide the framework against which that progress can be recorded. Civity’s approach to Biodiversity Net Gain therefore considers more than the initial sale of biodiversity units. Off-site BNG depends on habitats being created or enhanced, appropriately managed and documented over the long term so that the ecological outcomes supporting those units can be demonstrated. For developers, this provides greater confidence that off-site provision is backed by a structured long-term delivery framework. For landowners and habitat bank partners, it provides a clear route for turning habitat creation and enhancement into biodiversity units while understanding the ongoing responsibilities that accompany participation in the BNG market. Conclusion BNG monitoring and reporting is what turns a calculated biodiversity gain into a demonstrable long-term ecological outcome. The statutory framework requires relevant gains to be secured for at least 30 years, but successful BNG delivery depends on more than simply reaching that minimum period. Clear responsibilities, good baseline evidence, appropriate habitat management, repeatable monitoring and consistent reporting all contribute to demonstrating that biodiversity value is being delivered as intended. For developers purchasing off-site units, choosing a provider with robust arrangements for long-term habitat delivery can reduce uncertainty around the off-site element of the Biodiversity Gain Plan. For landowners, understanding the monitoring and management commitment before creating or selling units is essential to building a viable habitat bank. Through Civity, developers and landowners can access off-site BNG solutions that include long-term habitat delivery and documentation to turn biodiversity commitments into measurable outcomes.

An approved Biodiversity Gain Plan cannot simply be amended under the current Biodiversity Net Gain framework. If the approach to meeting the biodiversity gain objective changes after the plan has been approved but before development begins, a new Biodiversity Gain Plan can be submitted to the relevant planning authority for approval. Changes to a development layout, post-development habitats or off-site biodiversity provision may also affect the Biodiversity Metric, meaning the project’s calculations may need to be reviewed before a replacement plan is submitted. For developers, identifying these changes early is important. Starting development without the required Biodiversity Gain Plan approval, or proceeding in a way that does not comply with the approved BNG arrangements, can create planning and compliance risks. Can an Approved Biodiversity Gain Plan Be Amended? No. Government Biodiversity Net Gain planning guidance states that there is no mechanism for amending an approved Biodiversity Gain Plan. If the way a development will meet its biodiversity gain objective changes after the plan has been approved but before development commences, a new Biodiversity Gain Plan can instead be submitted to the planning authority for approval. For example, the government specifically identifies a change between registered off-site biodiversity gains and statutory biodiversity credits as a situation where a new plan could be required. Developers should therefore avoid treating an approved Biodiversity Gain Plan as a document that can simply be edited and reissued. Why Might a Biodiversity Gain Plan Need to Change? A new Biodiversity Gain Plan may be necessary where changes affect how the development will achieve its required biodiversity gain. This could arise because the development design changes, the proposed on-site habitat creation or enhancement is altered, or the project’s planned off-site biodiversity gains are no longer available. Changes affecting the development footprint are particularly important because the statutory Biodiversity Metric compares pre-development biodiversity value with post-development biodiversity value. If the approved layout changes which habitats will be retained, lost, created or enhanced, the post-development biodiversity calculation may also change. The project team should therefore review the Biodiversity Metric alongside any material design changes rather than assuming the original BNG strategy remains valid. Does the Biodiversity Metric Need to Be Recalculated? The Biodiversity Metric should be reviewed where a proposed change affects information used in the approved calculation, including the post-development biodiversity value or the project’s off-site unit requirement. The statutory Biodiversity Metric measures biodiversity value using factors associated with habitats, including their type, size, condition and strategic significance. Changes to the development footprint or proposed habitat creation and enhancement can therefore alter the post-development calculation. Importantly, once the pre-development biodiversity value has been established through an approved Biodiversity Gain Plan, that value does not change for that planning permission. This means recalculation following a design change is not an opportunity to establish a different baseline. Instead, the project team needs to assess the revised proposals against the established pre-development value and determine whether the biodiversity gain objective continues to be met. What Happens If the Development Layout Changes? A development layout change should trigger a review of the approved BNG strategy where it affects habitats, biodiversity enhancements or the development’s post-development biodiversity value. For example, a revised layout could increase the amount of habitat lost within the red line boundary, reduce space previously allocated for on-site habitat creation or alter a significant on-site habitat enhancement. Any resulting change in post-development biodiversity value could affect how many biodiversity units are needed to maintain the required net gain. The updated development may therefore need a revised biodiversity metric calculation and, where the approved approach to meeting the biodiversity gain objective has changed before commencement, a new biodiversity gain plan. BNG should consequently be considered alongside design revisions rather than reviewed only after the wider planning changes have been agreed. Can Off-Site BNG Units Be Changed After the Plan Is Approved? Changing off-site BNG units after they have been purchased, registered and allocated to a development can be difficult. In practice, developers should treat an allocation as effectively final once it has been made, rather than assuming biodiversity units can easily be swapped or reallocated later. The Biodiversity Gain Plan records the registered off-site biodiversity gains allocated to the development. Those units must correspond with the development’s biodiversity metric and satisfy the relevant habitat trading requirements. Natural England’s guidance on amending an allocation of off-site biodiversity gains provides only limited circumstances in which an allocation can be changed. An application can be made to reduce the area or length of an allocated habitat or remove a recorded allocation entirely. However, an allocation cannot be amended while it relates to an existing condition of planning permission. Evidence must be provided showing that the planning permission conditions connected with the allocation are no longer in place before Natural England can consider the amendment. The process also requires supporting information, including the statutory Biodiversity Metric for the allocated development reviewed by the approving local planning authority. Natural England advises that an allocation amendment application can take up to six weeks. This means developers should be confident that the units they are purchasing are suitable before they are formally allocated. Habitat type, trading rules, spatial risk, the development’s Biodiversity Metric requirements and the availability of the units should all be considered before the allocation is finalised. Securing appropriate off-site BNG units early can provide greater certainty over availability and cost, but the allocation itself should be approached carefully. Once units have been formally allocated to a development and are tied to its planning permission, reversing that decision is highly restricted rather than a straightforward administrative change. What Happens If a New Biodiversity Gain Plan Is Required? Where a new Biodiversity Gain Plan is required before commencement, it must be submitted to the relevant planning authority and approved before the development can begin under that permission. The plan should reflect the updated approach to meeting the biodiversity gain objective and be supported by the appropriate completed biodiversity metric calculation and evidence. Government guidance states that planning authorities normally have eight weeks to approve or refuse a Biodiversity Gain Plan unless a different timescale is agreed. This makes the timing of revisions important. Discovering shortly before the intended commencement date that a design or BNG delivery change requires a new plan can affect the development programme while the revised documentation is prepared and determined. Developers should therefore identify potential changes as early as possible and discuss the appropriate route with the relevant planning authority. What Happens If Planning Permission Is Varied Under Section 73? A Section 73 application can introduce additional BNG considerations because permission granted under Section 73 is a new planning permission linked to the original permission. Current Planning Practice Guidance contains specific provisions explaining how Biodiversity Net Gain applies to Section 73 permissions. In some circumstances, an earlier Biodiversity Gain Plan can effectively carry across to the new permission. However, where conditions attached to a new Section 73 permission affect the post-development biodiversity value, a Biodiversity Gain Plan for the new permission must be submitted and approved before development under that permission commences. The statutory biodiversity gain condition itself cannot be varied or removed through a Section 73 application. Developers changing an approved scheme should therefore consider BNG at the same time as the planning variation rather than assuming the existing Biodiversity Gain Plan automatically remains suitable. What Are the Rules for Phased Developments? Phased developments have a different Biodiversity Gain Plan process. They require an Overall Biodiversity Gain Plan for the development and individual Phase Biodiversity Gain Plans before each relevant phase begins. The government’s phased development guidance reflects the fact that large developments may evolve over a long period, and full details of later phases may not be known when planning permission is originally granted. The Overall Biodiversity Gain Plan establishes the framework for achieving at least the required biodiversity gain across the development. Each Phase Biodiversity Gain Plan then establishes how that individual phase contributes towards the overall objective. This structure provides greater flexibility for long-term schemes, but changes still need to be assessed carefully against the approved overall BNG strategy, relevant phase plan and statutory Biodiversity Metric. Can a Biodiversity Gain Plan Change After Development Has Started? The government’s specific route for submitting a new Biodiversity Gain Plan where the BNG approach has changed applies to changes made after approval but before commencement. Once development has commenced under an approved Biodiversity Gain Plan, developers should not assume the same process can be used to retrospectively replace the approved arrangements. The approved plan forms part of the framework through which compliance with the statutory biodiversity gain condition is demonstrated. Other planning obligations and legal agreements may also secure habitat delivery and long-term management. Where a change becomes necessary after commencement, the appropriate route will depend on the planning permission, the nature of the proposed change, any legal agreements and whether on-site or registered off-site gains are affected. The developer should therefore engage with the relevant planning authority and appropriate ecological and planning professionals before departing from the approved BNG arrangements. Do Habitat Management Agreements Need to Reflect BNG Changes? Changes affecting significant habitat creation or enhancement may also have implications for the documents and legal mechanisms securing those habitats. Significant on-site biodiversity gains and registered off-site biodiversity gains generally need to be secured for at least 30 years through the appropriate planning or legal mechanism. For off-site habitat banks, this can include a conservation covenant or planning obligation such as a Section 106 agreement. The Habitat Management and Monitoring Plan sets out how habitats will be established, managed and monitored over the required period and is likely to be referenced extensively within the legal agreement and appended as a key supporting document. If the proposed habitat delivery changes, the project team should therefore consider whether the relevant management arrangements and legal documentation also need to change. What Is the Planning Risk of Getting BNG Changes Wrong? Proceeding without the necessary Biodiversity Gain Plan approval can create a compliance issue because the biodiversity gain condition is a pre-commencement condition. For developments subject to mandatory BNG, planning permission is deemed to include the biodiversity gain condition. Development cannot begin until the Biodiversity Gain Plan has been approved. Local planning authorities also have an ongoing role in ensuring that developers and land managers meet their BNG commitments. Government guidance confirms that failure to meet BNG requirements can lead to enforcement action where a developer is in breach of planning conditions, planning obligations or a legal agreement. Failure to meet BNG requirements can lead to enforcement action where a developer is in breach of planning conditions, planning obligations or a legal agreement. There is also a practical commercial and administrative risk. If a revised biodiversity metric creates a larger or different off-site requirement late in the process, developers may need to secure additional biodiversity units at short notice. Amending biodiversity units that have already been formally allocated is considerably more complicated. Changes to an original allocation can require approval from the relevant local planning authority and an application to Natural England to amend the allocation on the Biodiversity Gain Sites Register. Natural England will not amend an allocation while it remains connected to an existing condition of planning permission, so the relevant planning position must first be resolved and appropriate evidence provided. Developers should therefore treat a formal allocation as effectively final and make sure the habitat type, number of units, trading rules and spatial requirements are correct before the allocation is completed. Early review of the Biodiversity Metric and off-site requirements can help avoid the need to unravel an existing allocation later in the planning process. How Can Developers Reduce the Risk of BNG Changes? Developers can reduce planning and commercial risk by reviewing the Biodiversity Metric whenever a material change to the development could affect habitat loss, retention, creation or enhancement. The ecological team should establish whether the change affects post-development biodiversity value and whether the existing BNG strategy still achieves the required outcome. Where off-site units are involved, developers should also check whether the type and quantity of units required have changed. Early communication between the developer, ecological consultant, planning team, local planning authority and off-site unit provider can help identify these issues before they affect the construction programme. If the project is still evolving, obtaining updated off-site quotations as the metric changes can also provide a more accurate picture of the financial implications of different design options. How Civity Supports Developers When BNG Requirements Change At Civity, we help developers understand the off-site implications of changes to their Biodiversity Metric. We do not undertake the developer’s biodiversity metric calculations. Instead, we interpret completed metric outputs supplied by the developer’s ecological team to establish the habitat types and number of off-site biodiversity units required. If a development layout changes and the ecological team produces an updated metric, we can quickly interpret the revised requirement and provide an updated quotation for suitable off-site units. We can also consider unit availability, habitat type, trading rules and location when identifying appropriate options. Where suitable units are in short supply or favourable pricing is available, developers may also be able to reserve units or secure them with a deposit before the final requirement is confirmed. This dynamic approach helps developers understand how changes to their scheme could affect off-site BNG costs without waiting until the Biodiversity Gain Plan is ready for final submission. Managing Biodiversity Gain Plan Changes Before They Become Delays An approved Biodiversity Gain Plan cannot simply be edited after approval. Where the approach to achieving the biodiversity gain objective changes before development starts, a new Biodiversity Gain Plan may need to be submitted and approved. Changing the details surrounding existing off-site biodiversity allocations is also not straightforward, particularly once units have been formally allocated and linked to the planning permission. Developers should therefore make sure proposed allocations are suitable before they are finalised. The key is identifying changes early. Development layouts, habitat proposals and off-site requirements can evolve throughout the planning process. Reviewing the Biodiversity Metric alongside those changes helps developers understand whether the required biodiversity gain is still being achieved and whether additional off-site units are needed. At Civity, we work with developers and their ecological teams to interpret changing off-site requirements and provide fast, updated quotations for suitable biodiversity units. If your project’s metric has changed or you need to understand the cost and availability of revised off-site BNG requirements, speak to Civity about your development biodiversity metric.

Strategic significance is a factor within the Biodiversity Metric that considers whether post-development habitat creation or enhancement is being delivered in locations identified as priorities for nature recovery. Where a published Local Nature Recovery Strategy (LNRS) identifies a mapped measure and the proposed habitat delivers that measure, the habitat can receive higher strategic significance within the statutory biodiversity metric. For developers, landowners and habitat bank providers, this means where and what habitat is created can influence its biodiversity value. Understanding the relationship between the Biodiversity Metric, LNRS mapping and local nature recovery priorities can therefore help inform both development design and off-site BNG delivery. What Does Strategic Significance Mean in the Biodiversity Metric? Strategic significance describes the local importance of a habitat based on its location and habitat type. Within the statutory biodiversity metric, it is used to encourage habitat creation and enhancement in locations where those interventions can contribute to wider nature recovery priorities. The metric does not simply measure the number of hectares being created or enhanced. Biodiversity units are influenced by several factors, including habitat distinctiveness, condition and strategic significance. For post-development habitats, strategic significance can therefore affect the number of biodiversity units generated by a proposed habitat creation or enhancement project. This applies to both on-site and off-site biodiversity gains, making strategic significance relevant to developers as well as landowners establishing habitat banks. What Is a Local Nature Recovery Strategy? A Local Nature Recovery Strategy (LNRS) is a statutory spatial strategy that identifies priorities and opportunities for nature recovery within a defined area of England. There are 48 LNRS areas covering England. Each strategy is led by an appointed responsible authority and contains two core components: a written statement of biodiversity priorities and a local habitat map. The government’s Local Nature Recovery Strategy guidance explains that these strategies identify where actions could make a particular contribution to nature recovery. An LNRS might identify opportunities to restore grassland, create wetlands, improve woodland, establish hedgerows, increase ecological connectivity between existing habitats, and/or deliver other relevant measures considered appropriate to the land in question. The aim is to encourage but not obligate individual habitat projects to contribute towards a wider, connected network for nature rather than operating as isolated biodiversity enhancements. How Does an LNRS Affect Strategic Significance? Where an LNRS has been published, its mapped measures are used to determine whether relevant post-development habitats can qualify for high strategic significance within the statutory biodiversity metric. A habitat does not receive a higher score simply because it sits somewhere inside an LNRS area. The proposed habitat must be in a location identified for the relevant mapped measure, and the nature recovery action associated with that location must be delivered. For example, if an LNRS identifies a particular area for species-rich grassland creation, creating the appropriate grassland in that mapped location may qualify for high strategic significance. If woodland planting were proposed in that same area instead, high strategic significance would not apply because the proposed habitat does not align with the measure identified by the LNRS. The statutory biodiversity metric then reflects that strategic alignment within the biodiversity unit calculation. This creates a direct relationship between local nature recovery priorities and the value generated through BNG. Can Strategic Significance Increase Biodiversity Units? Yes. High strategic significance can increase the biodiversity units generated by qualifying post-development habitat. Under the current statutory metric, high strategic significance has a multiplier of 1.15, compared with 1.0 for low strategic significance. In practical terms, qualifying habitat creation or enhancement can therefore receive a 15% uplift through this component of the metric. For example, if a qualifying post-development habitat would otherwise generate 10 units before strategic significance is applied, a 1.15 strategic significance multiplier could increase that component to 11.5 units, subject to the rest of the statutory biodiversity metric calculation. However, strategic significance cannot be used simply to make an otherwise unsuitable BNG proposal work. Habitat distinctiveness, condition, trading rules and other relevant metric factors still apply. How Do Local Plans Affect Strategic Significance? As of 27 August 2026, 43 of England’s 48 Local Nature Recovery Strategies (LNRSs) have been published, meaning most areas now have a formal LNRS that can be used when determining strategic significance within the statutory biodiversity metric. Where an LNRS has been published, it becomes the relevant strategic framework for determining high strategic significance for post-development habitats in accordance with the statutory metric guidance. Developers and ecological consultants should therefore review the published LNRS for the relevant area and establish whether proposed habitat creation or enhancement aligns with the measures identified within it. For the remaining areas where an LNRS has not yet been published, locally relevant plans and strategies may still need to be considered when assigning strategic significance. The current status of LNRS publication across England can be checked using the government’s map of LNRS areas and responsible authorities. Does Strategic Significance Affect Baseline Biodiversity Value? Where an LNRS has been published, baseline habitats are assigned low strategic significance under the current statutory metric approach. High strategic significance is instead available to qualifying post-development habitat creation and enhancement that delivers an appropriate mapped LNRS measure. This distinction helps create an incentive for new BNG delivery to support strategic nature recovery priorities. The baseline biodiversity value still depends on other important factors, including habitat type, size, distinctiveness and condition. Strategic significance does not replace those ecological assessments. Accurate baseline habitat information therefore remains essential when calculating pre-development biodiversity value. How Does Strategic Significance Affect Off-Site BNG? Strategic significance can affect the biodiversity value generated by an off-site habitat bank where habitat creation or enhancement aligns with a mapped LNRS measure. For landowners, this makes LNRS mapping an important consideration when assessing the potential of land for off-site BNG. Land that falls within a mapped opportunity and can practically and appropriately deliver the relevant habitat measure may be capable of generating additional biodiversity value through the strategic significance multiplier. However, that does not automatically make the land a commercially viable habitat bank. Existing habitats, ecological condition, achievable habitat enhancement, long-term management costs, local demand and the statutory metric’s trading rules all need to be considered. At Civity, we assess habitat bank opportunities from both an ecological and commercial perspective, helping landowners understand the potential biodiversity units that could be generated and whether there is likely to be developer demand for those units. Is Strategic Significance the Same as Spatial Risk? No. Strategic significance and spatial risk are separate elements of the statutory biodiversity metric. Strategic significance considers whether habitat creation or enhancement supports identified local nature recovery priorities. Spatial risk considers the geographic relationship between off-site biodiversity gains and the development site they are being used to compensate for. A habitat bank could therefore qualify for high strategic significance because it delivers a mapped LNRS priority while still being subject to a spatial risk adjustment when its units are allocated to a particular development. Developers purchasing off-site units need to consider both factors. For more detail on location, read our guide to the BNG Spatial Risk Multiplier and how the location of off-site units affects their effective value.

The BNG Spatial Risk Multiplier reduces the value of off-site biodiversity units when habitat compensation is located further from the biodiversity loss caused by a development. Under the current statutory biodiversity metric, area and hedgerow units within the same Local Planning Authority (LPA) or National Character Area (NCA) receive a multiplier of 1.0, neighbouring areas receive 0.75, and locations outside these areas receive 0.5. For developers using off-site biodiversity units to achieve biodiversity net gain, location can therefore directly affect how many units are required and, consequently, project costs. Understanding spatial risk early can help developers identify suitable units before finalising their BNG strategy and avoid sourcing units that lose a significant proportion of their value when entered into the statutory biodiversity metric. What Is the BNG Spatial Risk Multiplier? The BNG Spatial Risk Multiplier is a geographic scaling factor within the statutory biodiversity metric that reflects the relationship between biodiversity lost at a development site and habitat compensation delivered off-site. The principle is straightforward: off-site gains closer to the impact site retain more of their biodiversity unit value. More distant gains receive a reduced value within the metric. For area habitats and hedgerows, the current statutory metric applies the following spatial risk scores: Within: 1.0The off-site compensation is within the development site’s LPA boundary or National Character Area. Neighbouring: 0.75The compensation is outside the development site’s LPA or NCA but within a neighbouring LPA or NCA. Outside: 0.5The compensation is outside both the relevant and neighbouring LPA or NCA. This means an off-site habitat does not necessarily have to be within the same local planning authority to receive the full 1.0 multiplier. Being within the same National Character Area can also satisfy the current “within” category for area and hedgerow habitats. Why Does the Location of Off-Site BNG Units Matter? Location matters because the statutory biodiversity metric incentivises developers to deliver biodiversity gains close to where biodiversity is being affected. More distant off-site gains are discounted, which can increase the quantity of units needed to meet the development’s BNG requirement. This approach helps retain the ecological benefits of biodiversity enhancements closer to affected areas and local communities. For example, imagine that a habitat bank creates 10 biodiversity units before spatial risk is applied. If those units qualify for a 1.0 spatial risk multiplier, all 10 units retain their value for the development. At 0.75, the same 10 units contribute 7.5 units. At 0.5, they contribute only 5 units. The underlying habitat has not changed. What changes is the value attributed to those off-site gains for that particular development through the biodiversity metric. Government guidance confirms that biodiversity gains can be delivered anywhere in England, but the metric incentivises off-site gains closer to the development. It is therefore more accurate to say that developers are incentivised to source locally rather than saying off-site units must always come from the same LPA. How Do LPA and National Character Area Boundaries Affect Spatial Risk? For area habitats and hedgerows, the current metric considers both Local Planning Authority and National Character Area boundaries. An off-site site falling within either the same LPA or NCA as the impact site can receive the full 1.0 spatial risk score. This can considerably broaden the search area available to a developer. A habitat bank may sit outside the development site’s LPA but still share its National Character Area. In that situation, the units still qualify as “within” for spatial risk purposes. Conversely, a site outside both the relevant LPA and NCA may fall into the neighbouring or outside categories, reducing the effective biodiversity value of its units for that development. This is why searching for suitable off-site biodiversity units should consider both geographic frameworks rather than relying on the LPA boundary alone. Does the Spatial Risk Multiplier Work Differently for Watercourses? Yes. Watercourse habitats use catchment geography rather than LPA and National Character Area boundaries when determining spatial risk. Under the current statutory biodiversity metric, watercourse compensation within the same waterbody catchment receives a spatial risk score of 1.0. Compensation outside that waterbody catchment but within the operational catchment receives 0.75, while compensation outside the operational catchment receives 0.5. Different rules also apply to intertidal habitats, where Marine Plan Areas are used. Developers should therefore establish which habitat unit type they need before searching the private market for off-site BNG units. How Can Spatial Risk Increase the Number of BNG Units Required? A spatial risk deduction can mean a developer needs to purchase a greater quantity of off-site units because each unit contributes less towards the development’s BNG requirement. For example, suppose a development needs 6 effective off-site area habitat units. If suitable units qualify for the 1.0 multiplier, 6 units provide the required value. If otherwise suitable units receive a 0.75 multiplier, approximately 8 raw units would be needed to provide 6 effective units, subject to the wider metric calculation and trading rules. If the units receive a 0.5 multiplier, approximately 12 raw units would be required to provide the same 6 effective units. This simplified example demonstrates why the cheapest advertised unit price is not necessarily the cheapest solution for a development. Unit location and effective value need to be considered alongside price. How Does Spatial Risk Affect Project Costs? The Spatial Risk Multiplier can increase BNG costs because a lower multiplier may require the developer to secure more units to address the same biodiversity deficit. Developers comparing off-site options should therefore consider the effective cost of satisfying their requirement rather than comparing biodiversity units purely on their headline price. A lower-priced habitat bank further from the development could ultimately require more units. A more local habitat bank with a 1.0 multiplier could require fewer units and potentially provide a more efficient solution. Other factors remain important too. Habitat type, trading rules, availability, and the specific unit deficit identified in the developer’s biodiversity metric all influence which off-site solution is appropriate. This makes early assessment particularly valuable for financial planning. What Is the Difference Between Spatial Risk and Strategic Significance? Spatial risk and strategic significance are separate components of the biodiversity metric. Spatial risk considers the geographic relationship between the development’s biodiversity loss and off-site compensation, while strategic significance considers whether habitat creation or enhancement is located in an area identified as strategically important for nature recovery. Local Nature Recovery Strategies identify priorities and potential measures for recovering or enhancing biodiversity within their strategy areas. A habitat bank can therefore have advantages because of its strategic location, while spatial risk is considered separately within the metric. Developers should not assume that a strategically significant habitat automatically avoids a spatial risk deduction. Both factors need to be correctly entered and assessed within the statutory biodiversity metric. Do BNG Trading Rules Still Apply to Local Off-Site Units? Yes. A favourable BNG Spatial Risk Multiplier does not override the statutory metric’s trading rules. Trading rules help prevent losses of more valuable habitats from being compensated through inappropriate lower-distinctiveness habitats. Developers therefore need to source the right habitat types and biodiversity units, not simply the closest available units. A habitat bank within the same LPA or National Character Area may receive a spatial risk score of 1.0 but still be unsuitable if its available units do not satisfy the development’s habitat requirements and trading rules. The correct approach is therefore to consider habitat type, distinctiveness, unit availability, trading rules and spatial risk together. When Should Developers Start Looking for Off-Site BNG Units? Developers should investigate off-site options once their biodiversity metric is sufficiently developed to indicate the likely type and quantity of off-site units required. Waiting until the final stages of the planning process can reduce the range of available units, particularly where specific habitat types are in demand. Early market assessment allows developers to compare habitat banks across the relevant LPA and National Character Area, understand how the Spatial Risk Multiplier affects each option and obtain realistic cost information. The metric may change as the development layout evolves. Updated calculations can therefore be used to obtain revised quotations and understand how design decisions affect the off-site requirement. Where the right unit type is in short supply or favourable pricing is available, developers may also wish to explore whether units can be reserved or secured with a deposit. How Does Spatial Risk Relate to the Biodiversity Gain Plan? Where off-site units form part of a development’s BNG strategy, the final biodiversity metric calculation and off-site allocation feed into the Biodiversity Gain Plan. Off-site gains must be registered on the Biodiversity Gain Sites Register and allocated to the relevant development before they can count towards its BNG requirement. The local planning authority can then check that the off-site gains included within the Biodiversity Gain Plan correspond with the relevant registered allocation. This makes selecting suitable off-site provision more than a procurement decision. The units need to work within the statutory biodiversity metric, satisfy applicable trading rules and be correctly registered and allocated. How Do Statutory Biodiversity Credits Compare? Statutory biodiversity credits are a last-resort option where a developer cannot achieve the required biodiversity net gain through on-site or off-site delivery. A spatial risk adjustment also applies to statutory biodiversity credits. Each statutory credit provides 0.5 biodiversity units, meaning developers need to purchase two statutory credits for every one biodiversity unit required. Credits are priced in tiers according to habitat type, with different prices applying depending on the habitat being compensated. This can make statutory credits a significantly more expensive option than securing suitable off-site biodiversity units, reinforcing the importance of exploring appropriate private-market off-site solutions first. How Civity Helps Developers Find Suitable Off-Site BNG Units At Civity, we help developers interpret the completed biodiversity metric outputs supplied by their ecological team and identify the off-site biodiversity units required to satisfy their remaining BNG obligation. We do not undertake the developer’s biodiversity metric calculation. Instead, we use the completed metric to understand the required habitat types and unit quantities before identifying suitable off-site options. Location forms an important part of that process. We can consider the development site’s LPA and National Character Area alongside our available habitat bank units to understand how spatial risk may affect the value of different options. We can then provide fast quotations for suitable off-site BNG units, helping developers compare the commercial implications of their available options. Because development layouts and biodiversity metric calculations often evolve, Civity can also provide revised quotations as the unit requirement changes. This gives project teams greater visibility over potential BNG costs throughout the planning process. Our work with habitat banks and landowners also gives us visibility across the supply side of the BNG market, helping connect appropriate habitat creation and enhancement opportunities with genuine developer demand. Why Early Site Selection Matters for Off-Site BNG The location of off-site biodiversity units can materially change their effective value within the statutory metric, making site selection an important part of a developer’s BNG strategy. Under the current rules, area and hedgerow units within the same LPA or National Character Area can retain their full value through a 1.0 spatial risk multiplier. Neighbouring locations receive 0.75, while more distant provision receives 0.5. However, proximity is only part of the decision. Suitable units must also meet the project’s habitat requirements and statutory trading rules. By assessing spatial risk, habitat type, availability and price together, developers can make more informed decisions about their off-site BNG strategy and understand the likely cost before their Biodiversity Gain Plan is finalised. For support identifying and pricing suitable off-site units, speak to Civity about your development’s BNG requirements.

Since mandatory biodiversity net gain (BNG) became a legal requirement in England on 12 February 2024, biodiversity has become a central consideration within the planning process. Before development can begin, local planning authorities must approve a biodiversity gain plan demonstrating how a development will achieve at least a 10% increase in biodiversity value. Many developers assume that submitting biodiversity metric calculations alone is enough. In practice, local planning authorities look for much more than a final biodiversity score. They want evidence that biodiversity net gain requirements have been properly considered throughout the design process, that biodiversity gains are realistic and deliverable, and that they will be maintained for at least 30 years. Understanding what local planning authorities actually look for can help reduce planning risk, avoid delays and improve the likelihood of securing planning permission. The Purpose of a Biodiversity Gain Plan A biodiversity gain plan is the document that shows how a development will achieve biodiversity net gain and satisfy the biodiversity gain condition attached to planning permissions. It accompanies the finalised statutory biodiversity metric tool and comprises a simple pro-forma, onto which a number of other documents and agreements may be appended depending on the complexity of the project. Under the statutory framework, local planning authorities must approve the biodiversity gain plan before development starts. LPAs generally have up to eight weeks to determine whether the submitted gain plan satisfies biodiversity net gain requirements. The gain plan forms part of the wider biodiversity net gain BNG process and demonstrates how biodiversity value will be protected, enhanced and maintained throughout the lifecycle of a development project. Accurate Baseline Biodiversity Value Calculations One of the first things planning authorities assess is whether the baseline biodiversity value has been calculated correctly. The pre-development biodiversity value establishes the benchmark against which biodiversity gain is measured. Local planning authorities will expect developers to provide accurate habitat surveys undertaken by suitably qualified professionals and supported by ecological expertise. The statutory biodiversity metric tool must be used to calculate the baseline biodiversity value. Published by Natural England, the current biodiversity metric calculates biodiversity units based on habitat size, condition and distinctiveness. Local planning authorities will review whether the baseline biodiversity has been assessed accurately within the red line boundary and whether existing habitat conditions have been properly recorded. Evidence That the Biodiversity Gain Hierarchy Has Been Followed Many local planning authorities place significant emphasis on the biodiversity gain hierarchy and mitigation hierarchy. Before considering off-site biodiversity units, developers must demonstrate that opportunities to avoid biodiversity loss have been fully explored. Planning officers want to see evidence that site layouts have been designed to retain valuable habitats, protect biodiversity and minimise impacts on wildlife habitats and wildlife species. Particular attention is often given to irreplaceable habitats. LPAs will check that adverse impacts on irreplaceable habitats have been minimised and that statutory requirements relating to these habitats have been followed. Where biodiversity losses cannot be avoided, authorities expect developers to maximise habitat enhancement and habitat creation opportunities within the development site before relying on off-site gains. Robust Biodiversity Metric Calculations A biodiversity gain plan must contain clear and transparent biodiversity metric calculations. Planning authorities will review both the pre-development biodiversity value and the projected post-development biodiversity value to ensure that the biodiversity gain objective is being met. The statutory biodiversity metric measures biodiversity value before and after development and calculates whether sufficient biodiversity units have been delivered to achieve mandatory biodiversity net gain. Authorities will scrutinise habitat creation assumptions, habitat enhancement works, habitat condition targets and delivery timescales. Unrealistic assumptions can result in requests for additional information or delays to approval. Clear On-Site Biodiversity Proposals Local planning authorities generally prefer biodiversity gains to be achieved on site wherever possible. A strong biodiversity gain plan should clearly explain how biodiversity gains will be delivered through habitat creation, habitat enhancement and green infrastructure. This may include new woodland planting, species-rich grassland creation, wetland features, wildlife corridors or other measures designed to enhance biodiversity. Planning officers will assess whether proposed habitats are appropriate for the location and whether they contribute positively to the natural environment and local nature recovery objectives. Developers should clearly explain how much biodiversity gain can be achieved on site and how these measures contribute to the overall net gain target. Should proposed on-site habitats that contribute to the overall net gain score require specific management regimes, it may be necessary to append a detailed habitat management plan and a 30+ year legal commitment to enact that plan (such as a Section 106 agreement). Appropriate Off-Site Biodiversity Gains Where sufficient biodiversity units cannot be achieved on site, LPAs will assess proposed offsite biodiversity units carefully. If biodiversity gain requirements cannot be achieved on-site, off-site biodiversity gains must be legally secured and registered. Local planning authorities will expect evidence that the proposed biodiversity gain site appears on the Biodiversity Gain Site Register maintained by Natural England. Authorities will also review whether off-site gain sites align with local nature recovery strategies and broader local nature recovery priorities. Sites that contribute to strategic ecological objectives often carry greater strategic significance within the statutory biodiversity metric. Many local planning authorities favour off-site biodiversity units located within their own authority area where possible, particularly where these support local habitat creation priorities. Legal Agreements and Long-Term Security One of the most important aspects of any biodiversity gain plan is demonstrating that biodiversity gains will be maintained over the long term. Biodiversity net gain must be secured for a minimum of 30 years. Local authorities therefore require evidence that appropriate legal agreements are in place. For offsite biodiversity units, this may involve conservation covenants with a responsible body or planning obligations secured through Section 106 agreements. These legal mechanisms ensure biodiversity gain commitments remain enforceable long after planning permission has been granted. Planning authorities will often review the legal agreement alongside the biodiversity gain plan to ensure habitats are properly protected. Habitat Management and Monitoring Plans (HMMPs) Delivering biodiversity gain is only part of the requirement. Authorities also want to understand how habitats will be managed. A detailed monitoring plan should explain how biodiversity gains will be maintained and monitored over the required 30-year period. The management plan should identify responsibilities, maintenance activities, performance indicators and reporting arrangements. If purchasing biodiversity units from an offset provider such as Civity, they will have their own pre-approved HMMP; however, if providing your own habitats, you may be expected to produce your own project-specific HMMP and to secure it via an appropriate legal agreement over the 30-year period.  Local planning authorities have a duty to monitor biodiversity gains and verify compliance throughout the management period. As a result, clear environmental management arrangements are increasingly important within planning submissions. Off-Site Units and Statutory Biodiversity Credits Where offsite biodiversity units are required, planning authorities will expect developers to provide evidence that those units have been secured appropriately. This includes demonstrating that the biodiversity value of the proposed gains equals or exceeds the value being claimed within the biodiversity metric calculations. Where developers intend to buy statutory biodiversity credits, LPAs will typically require evidence that statutory credits have been purchased. However, statutory biodiversity credits are intended as a last resort and should only be used where suitable off-site biodiversity gains cannot be secured through the private market. It will be necessary to demonstrate to the LPA that it was not practicable to produce units or purchase them from an offset provider before resorting to purchasing statutory credits. The biodiversity Gain Plan template stipulates that at least three offset providers or a negative search result from online registers is required as evidence, but this should be treated as a minimum requirement and LPAs may have more detailed thresholds. Alignment with Local Nature Recovery Strategies Local nature recovery strategies are becoming increasingly influential within planning decision-making. Many local planning authorities assess whether biodiversity gains contribute towards local nature recovery priorities. Habitat creation proposals that support strategic ecological networks, wildlife habitats and biodiversity enhancement objectives are often viewed more favourably. Developers who align biodiversity gain plans with local nature recovery strategies can often strengthen their planning submissions while delivering wider environmental benefits. How Civity Supports Biodiversity Gain Plan Preparation At Civity, we support developers throughout the biodiversity net gain process, from baseline biodiversity assessments and statutory biodiversity metric calculations through to biodiversity gain plan preparation and off-site biodiversity unit procurement. Our team works closely with developers, ecologists, land managers and local planning authorities to ensure biodiversity gain plans are robust, compliant and aligned with planning policy requirements. We also help clients identify suitable habitat banks, secure offsite biodiversity units and navigate the legal requirements associated with conservation covenants and planning obligations. Conclusion What local planning authorities actually look for in a biodiversity gain plan goes far beyond achieving a numerical biodiversity target. Planning authorities want evidence that baseline biodiversity has been assessed correctly, that the biodiversity gain hierarchy has been followed, that biodiversity units are calculated accurately and that habitats will be managed successfully for at least 30 years. Developers who address these requirements early and prepare a comprehensive biodiversity gain plan are far more likely to achieve planning permission efficiently while delivering meaningful biodiversity gains for the natural environment.