Biodiversity Net Gain (BNG)

Planning-Ready BNG Support for Development & Infrastructure

View All Ecology & Biodiversity Services

Strategy, Assessment & Habitat Plans

At Arthian, our ecology consultants deliver Biodiversity Net Gain (BNG) services to assist clients in meeting their planning requirements or other commitments to ecology and long-term biodiversity outcomes. Whether you’re designing housing, infrastructure or energy projects, we provide clear, regulator-aligned support from early feasibility through to post-construction monitoring.

We support developers, planners and land managers across the UK, working on:

Residential and mixed-use developments
Infrastructure corridors for roads, rail, water and utilities
Energy, minerals and waste sites
Strategic land and regeneration schemes

BNG is now a mandatory requirement in England under the Environment Act 2021. Most developments must demonstrate a minimum 10% net gain in biodiversity value, maintained for at least 30 years.

Supporting Biodiversity in a Changing World – Biodiversity Net Gain for Corridor Infrastructure Projects

We specialise in delivering BNG across linear infrastructure schemes, including:

Route corridor assessments for roads, rail, water and utilities
Habitat connectivity and fragmentation mitigation
Multi-parcel BNG strategy coordination
Off-site habitat delivery across landowner networks
Integration with ecological constraints mapping and protected species mitigation

Our team understands the spatial, logistical and ecological challenges of corridor projects – ensuring BNG is deliverable, defensible and cost-effective. We also support BNG feasibility studies, stakeholder engagement, and integration with wider EIA and planning documentation.

Our Biodiversity Net Gain Services

We offer end-to-end BNG support, tailored to your site, planning context and delivery strategy. Our services include:

BNG Strategy Development

Defra Biodiversity Metric Calculation

Habitat Creation & Enhancement Plans

Habitat Management & Monitoring Plans (HMMP)

Off-Site BNG Solutions

BNG Reporting for Planning Applications

Post-Construction Monitoring

BNG Strategy Development

We provide early-stage advice to help embed biodiversity into site design, ensuring that Biodiversity Net Gain (BNG) is achievable, proportionate, and aligned with project goals. Our strategies are tailored to each site, helping to avoid constraints, minimise risk and maximise ecological value from the outset. This proactive approach supports smoother planning outcomes and long-term environmental benefits.

Our BNG strategy services include:

Site appraisal and baseline habitat assessments
Identification of constraints and opportunities for biodiversity enhancement
Integration of BNG into masterplanning and design development
Calculation of biodiversity units using the latest Defra metric
Advice on on-site and off-site delivery options
Liaison with planning authorities and stakeholders

Defra Biodiversity Metric Calculation

We carry out biodiversity unit calculations using the latest Defra metric tools to support Biodiversity Net Gain (BNG) assessments and planning submissions. Our work includes both baseline and post-development evaluations, helping to quantify ecological change and guide enhancement strategies. Baseline and post-development unit calculations using the latest Defra metric tools ensure that BNG is measurable, transparent, and aligned with regulatory requirements.

Our services include:

Habitat classification and condition assessments
Baseline biodiversity unit calculations
Post-development unit forecasts based on proposed designs
Use of the latest Defra biodiversity metric tools and guidance
Advice on achieving mandatory BNG targets
Integration with BNG strategies and planning documentation

Habitat Creation & Enhancement Plans

We design and deliver habitat proposals that support Biodiversity Net Gain (BNG) and long-term ecological resilience. Our plans are tailored to site conditions and project goals, ensuring that enhancements are practical, measurable, and aligned with local priorities. Design of on-site and off-site habitat proposals, aligned with Local Nature Recovery Strategies, helps maximise ecological value and contribute to strategic conservation outcomes.

Our services include:

Design of new habitats including grassland, woodland, wetland and hedgerows
Enhancement of existing habitats to improve condition and connectivity
Alignment with Local Nature Recovery Strategies and planning policy
Advice on on-site vs. off-site delivery options
Integration with BNG metric calculations and planning submissions
Monitoring and management plans to support long-term success

Habitat Management & Monitoring Plans (HMMP)

We develop long-term habitat management and monitoring plans to ensure that biodiversity enhancements are sustained and effective over time. These plans support planning condition discharge and demonstrate compliance with Biodiversity Net Gain (BNG) and protected species licensing requirements. Long-term management plans to support planning condition discharge and legal compliance provide a clear framework for maintaining ecological value and meeting regulatory expectations.

Our HMMP services include:

Development of tailored habitat management objectives
Monitoring protocols to assess habitat condition and success
Timetabled actions for habitat maintenance and enhancement
Reporting frameworks to support planning and licensing compliance
Integration with BNG strategies and ecological mitigation plans
Liaison with stakeholders and land managers to support delivery

Off-Site BNG Solutions

We help clients identify and secure off-site Biodiversity Net Gain (BNG) solutions where on-site delivery is limited or not feasible. Our approach ensures that off-site measures are strategically located, legally robust, and aligned with local conservation priorities. Identification of offset sites, habitat banks and Section 106/conservation covenant mechanisms supports compliance with statutory BNG requirements and contributes to wider ecological networks.

Our services include:

Identification and appraisal of suitable offset sites
Engagement with habitat banks and landowners
Advice on Section 106 agreements and conservation covenants
Coordination with Local Nature Recovery Strategies
Integration with BNG metric calculations and planning submissions
Monitoring and reporting to demonstrate long-term delivery

BNG Reporting for Planning Applications

We produce clear, planning-ready Biodiversity Net Gain (BNG) reports to support successful applications and demonstrate compliance with statutory requirements. Our reports combine metric outputs, mapping, and ecological justification to provide a robust evidence base for decision-making. Planning-ready reports including metric outputs, mapping and mitigation hierarchy justification ensure that biodiversity is fully considered and clearly communicated throughout the planning process.

Our reporting services include:

Biodiversity metric calculations and summary outputs
High-quality mapping of baseline and proposed habitats
Justification of design decisions using the mitigation hierarchy
Integration with ecological impact assessments and planning documents
Support for statutory BNG compliance under the Environment Act
Liaison with planning authorities and consultees

Post-Construction Monitoring

We carry out ongoing ecological monitoring following project completion to ensure that Biodiversity Net Gain (BNG) commitments are being met. Our surveys and reporting provide clear evidence of habitat establishment and species use, supporting compliance and long-term stewardship. Ongoing ecological surveys and reporting to demonstrate BNG delivery over time help satisfy planning conditions and inform adaptive management where needed.

Our services include:

Scheduled post-construction ecological surveys
Monitoring of habitat condition and species presence
Data analysis to track progress against BNG targets
Preparation of compliance reports for planning authorities
Advice on adaptive management and corrective actions
Integration with Habitat Management & Monitoring Plans (HMMP)

BNG Strategy Development

Our BNG strategy services include:

Site appraisal and baseline habitat assessments
Identification of constraints and opportunities for biodiversity enhancement
Integration of BNG into masterplanning and design development
Calculation of biodiversity units using the latest Defra metric
Advice on on-site and off-site delivery options
Liaison with planning authorities and stakeholders

Defra Biodiversity Metric Calculation

Our services include:

Habitat classification and condition assessments
Baseline biodiversity unit calculations
Post-development unit forecasts based on proposed designs
Use of the latest Defra biodiversity metric tools and guidance
Advice on achieving mandatory BNG targets
Integration with BNG strategies and planning documentation

Habitat Creation & Enhancement Plans

Our services include:

Design of new habitats including grassland, woodland, wetland and hedgerows
Enhancement of existing habitats to improve condition and connectivity
Alignment with Local Nature Recovery Strategies and planning policy
Advice on on-site vs. off-site delivery options
Integration with BNG metric calculations and planning submissions
Monitoring and management plans to support long-term success

Habitat Management & Monitoring Plans (HMMP)

Our HMMP services include:

Development of tailored habitat management objectives
Monitoring protocols to assess habitat condition and success
Timetabled actions for habitat maintenance and enhancement
Reporting frameworks to support planning and licensing compliance
Integration with BNG strategies and ecological mitigation plans
Liaison with stakeholders and land managers to support delivery

Off-Site BNG Solutions

Our services include:

Identification and appraisal of suitable offset sites
Engagement with habitat banks and landowners
Advice on Section 106 agreements and conservation covenants
Coordination with Local Nature Recovery Strategies
Integration with BNG metric calculations and planning submissions
Monitoring and reporting to demonstrate long-term delivery

BNG Reporting for Planning Applications

Our reporting services include:

Biodiversity metric calculations and summary outputs
High-quality mapping of baseline and proposed habitats
Justification of design decisions using the mitigation hierarchy
Integration with ecological impact assessments and planning documents
Support for statutory BNG compliance under the Environment Act
Liaison with planning authorities and consultees

Post-Construction Monitoring

Our services include:

Scheduled post-construction ecological surveys
Monitoring of habitat condition and species presence
Data analysis to track progress against BNG targets
Preparation of compliance reports for planning authorities
Advice on adaptive management and corrective actions
Integration with Habitat Management & Monitoring Plans (HMMP)

Why Choose Arthian's Ecology team?

Planning-aligned BNG consultancy with UK-wide coverage, with a proven track record supporting housing, infrastructure and energy sectors

Corridor ecology expertise for linear infrastructure projects

Integrated support from ecology, GIS, contaminated land and permitting teams

Responsive, pragmatic and regulator-aligned service delivery , trusted by developers, planners and local authorities

Frequently Asked Questions

When should I start planning for Biodiversity Net Gain?

BNG should be considered as early as possible in the project lifecycle. Early engagement allows:

Strategic design to maximise BNG score

Cost-effective mitigation and offsetting

Avoidance of planning delays and redesign

Alignment with other environmental priorities (e.g. carbon, flood risk, amenity)

We work closely with design teams, planning consultants and land managers to embed BNG into project strategy from the outset.

Is Biodiversity Net Gain mandatory?

Yes—BNG is mandatory for most developments in England under the Environment Act 2021.

How is BNG calculated?

Using the Defra Biodiversity Metric, which assesses habitat type, condition, distinctiveness and strategic significance.

Can BNG be delivered off-site?

Yes—off-site delivery is permitted where on-site options are limited, subject to legal agreements and long-term management.

Do you provide BNG monitoring and reporting?

Absolutely. We offer post-construction monitoring and reporting to support planning condition discharge and long-term compliance.

Get in Touch

We’d love to hear from you – whether you have a question, a project in mind, want to explore job opportunities, or just want to say hello.

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Environment

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Biodiversity Net Gain (BNG)

Strategy, Assessment & Habitat Plans

Supporting Biodiversity in a Changing World – Biodiversity Net Gain for Corridor Infrastructure Projects

Our Biodiversity Net Gain Services

BNG Strategy Development

Defra Biodiversity Metric Calculation

Habitat Creation & Enhancement Plans

Habitat Management & Monitoring Plans (HMMP)

Off-Site BNG Solutions

BNG Reporting for Planning Applications

Post-Construction Monitoring

BNG Strategy Development

Defra Biodiversity Metric Calculation

Habitat Creation & Enhancement Plans

Habitat Management & Monitoring Plans (HMMP)

Off-Site BNG Solutions

BNG Reporting for Planning Applications

Post-Construction Monitoring

Why Choose Arthian's Ecology team?

Corridor ecology expertise for linear infrastructure projects

Integrated support from ecology, GIS, contaminated land and permitting teams

Responsive, pragmatic and regulator-aligned service delivery , trusted by developers, planners and local authorities

Frequently Asked Questions

When should I start planning for Biodiversity Net Gain?

Is Biodiversity Net Gain mandatory?

How is BNG calculated?

Can BNG be delivered off-site?

Do you provide BNG monitoring and reporting?

Get in Touch