BNG Biodiversity Net Gain Monitoring Survey Checklist for UK Developers
Biodiversity Net Gain (BNG) monitoring is now mandatory for most planning applications in England. This checklist covers every stage — from baseline survey through to the 30-year monitoring commitment.
What Is BNG Monitoring?
BNG requires developers to deliver a minimum 10% net gain in biodiversity, secured for at least 30 years under the Environment Act 2021. Monitoring ensures habitats reach and maintain target conditions throughout this period.
Pre-Development Checklist
- [ ] Complete baseline habitat survey by a competent ecologist
- [ ] Calculate biodiversity value using Defra's Statutory Biodiversity Metric 4.0
- [ ] Draft Habitat Management and Monitoring Plan (HMMP) with an ecologist
- [ ] Include statement of ecological competence in HMMP
- [ ] Submit draft HMMP with planning application
- [ ] Confirm whether development is exempt from BNG (small sites, brownfield, etc.)
- [ ] Identify whether BNG will be delivered on-site, off-site, or via statutory credits
Planning Submission Checklist
- [ ] Biodiversity Gain Plan submitted to Local Planning Authority
- [ ] Baseline habitat survey included with UK Hab classification
- [ ] Defra Statutory Biodiversity Metric 4.0 calculation submitted
- [ ] Draft HMMP included with management prescriptions
- [ ] Monitoring schedule confirmed (years 2, 5, 10, 20, 30 for most habitats)
- [ ] Legal securing mechanism confirmed (Section 106, conservation covenant, or planning condition)
- [ ] Habitat creation/enhancement schedule included
- [ ] Restoration plan drafted for habitat failure scenarios
- [ ] Responsibilities for management and monitoring assigned
BNG Monitoring Plan (HMMP) Requirements
Core HMMP Components
| Component | What to Include | | --- | --- | | Management activities | Habitat creation/enhancement, timing, methods (seed mixes, cutting regimes, grazing density) | | Monitoring schedule | When and how monitoring will be conducted (varies by habitat type) | | Reporting | When and how results are reported to the LPA | | Management review | When and how management will be adjusted if targets are not met | | Restoration plan | How biodiversity value will be restored if habitat fails to reach target condition | | Responsibilities | Who creates, enhances, maintains, manages, and monitors over 30 years | | Legal restrictions | Planning obligations, conservation covenants, or other legal requirements |
HMMP Tools and Templates
| Tool | Purpose | | --- | --- | | Natural England HMMP template | Main template with habitat condition tables | | HMMP checklist | Reflects template headings for completion | | Monitoring Report Template (MRT) | For recording survey outcomes at each monitoring visit | | Small sites template | Simplified version for small development sites |
Post-Development Monitoring Checklist
Year 1
- [ ] Submit Biodiversity Gain Plan before development starts
- [ ] Confirm habitat creation/enhancement per HMMP schedule
- [ ] Conduct baseline-as-built survey immediately after habitat creation
- [ ] Submit initial monitoring report
Years 2–5
- [ ] Conduct Year 2 monitoring survey (standard for most habitats)
- [ ] Submit monitoring report with habitat condition data
- [ ] Assess against HMMP condition targets
- [ ] Adjust management prescriptions if targets not met
- [ ] Continue annual or bi-annual monitoring as required
Years 6–30
- [ ] Conduct monitoring surveys per agreed schedule (typically 5-yearly)
- [ ] Submit monitoring reports at Years 6, 11, 16, 21, 26, 30
- [ ] Implement restoration plan if any habitat fails condition targets
- [ ] Review and update management prescriptions as needed
2025 BNG Monitoring Survey Costs
| Cost Component | Range (ex VAT) | | --- | --- | | Baseline habitat survey | £800–£3,000+ | | BNG Metric calculation | £500–£2,000 | | HMMP drafting | £500–£2,500 | | Per monitoring visit | £570–£1,140 | | Monitoring report | £300–£800 per report | | 30-year programme (up to 100 dwellings) | ~£4,560 over 30 years | | 30-year programme (100–500 dwellings) | ~£9,120 over 30 years |
Note: LPA monitoring fees are set by the council — confirm directly with your local planning authority.
Frequently Asked Questions
Q: Who conducts BNG monitoring surveys?
A qualified ecologist with experience in UK Hab classification and habitat condition assessment. They must demonstrate competence in the HMMP.
Q: What happens if habitats don't meet condition targets?
The HMMP must include a restoration plan. If habitat fails to reach target condition, additional management measures must be implemented, and monitoring continues until targets are met.
Q: Can BNG monitoring be handed over to a third party?
Yes — management and monitoring responsibilities can be transferred to a responsible body (e.g., local wildlife trust, land management company) as long as the transfer is legally secured.
Q: What is the Monitoring Report Template (MRT)?
The MRT is Defra's standard template for recording survey outcomes at each monitoring visit. It captures habitat type, extent, condition scores, and compliance with HMMP targets.
Q: Can small sites use a simplified HMMP?
Yes — Natural England provides a separate HMMP template for small sites. Small site thresholds should be confirmed with your LPA.
Q: What habitats require more frequent monitoring?
Wetland habitats, species-rich grassland, and woodland habitats typically require more frequent visits in early years. Confirm the schedule with your ecologist.