NaFRA2 Guidance: Flood Map for Planning Updates

Understanding NaFRA2 and Its Impact on Flood Risk Assessments

The Environment Agency (EA) has today provided new guidance on how NaFRA2 data will shape the future of the Flood Map for Planning. These updates will significantly influence local planning policies, Flood Risk Assessments (FRAs), and Sequential Testing.

Key Changes in the Flood Map for Planning

Expanded Flood Zone Coverage and Small Watercourses Inclusion

The EA confirms that the revised Flood Map for Planning will include:

• Updated Flood Zones based on NaFRA2 data.
• Present-day and future flood risk extents for rivers and the sea, both in defended and undefended scenarios.
• Surface water flood risk extents, improving flood risk analysis.

A significant improvement is the inclusion of smaller watercourses in Flood Zones. Previously, flood mapping covered only watercourses with catchment areas greater than 3km². The new model will incorporate smaller catchments, potentially adding new Flood Zones.

Defended Scenario for Flood Zone 3b

For the first time, the EA is introducing a 1:30-year defended fluvial/tidal flood extent to aid LPAs in defining Flood Zone 3b (functional floodplain). This is crucial for floodplain management and planning applications.

Enhanced Surface Water Modelling for Sequential Testing

The new surface water flood risk extents are designed to assist LPAs in ranking flood risk for Sequential Testing. Notable enhancements include:

• Better represent building footprints to reflect their impact on flow routes.
• Correcting misinterpretations of previous surface water flood maps, which mistakenly suggested certain buildings would remain dry.
• Focusing on flood risk to land rather than individual properties.

Modelled Flood Depths – Not Yet Available

The EA has stated that fluvial, tidal, and surface water flood depths will not be included in the initial release but are planned for future updates.

Climate Change Allowances Aligned with Government Policy

The revised Flood Map for Planning incorporates climate change allowances for fluvial and tidal flooding in accordance with current UK Government flood risk assessment guidance.

Planning and Development Implications

Early Access and Transitional Arrangements for LPAs

The EA has confirmed that LPAs will receive early access to updated Flood Zone data before its public release. This allows them to:

• Screen new planning applications for FRAs, Sequential Tests, and Exception Tests.
• Assess ongoing applications using the latest flood risk data.

Expected Stability of Flood Zones

In areas with detailed local flood models, Flood Zones are expected to remain largely unchanged. However, regions relying on National Modelling may experience notable variations in their Flood Zones.

Impact on Strategic Flood Risk Assessments (SFRAs) and Local Plans

The EA's guidance confirms that SFRAs and Local Plans must be updated once the new Flood Map for Planning goes live. Developers and consultants should ensure their planning applications remain aligned with these changes.

Policy and Guidance Updates

• The National Planning Policy Guidance (NPPG) is set for an update, following the 2024 revisions to the National Planning Policy Framework (NPPF).
• The UK Government is expected to revise planning guidance related to the Sequential Test requirements, but no timeline has been provided.

Next Steps for Developers and Planning Professionals

While these updates are not yet in effect, professionals should proactively:

• Stay informed about the EA’s evolving guidance on the Flood Map for Planning.
• Engage early with LPAs to determine how upcoming changes may impact planning applications and site allocations.
• Prepare for updates to SFRAs and Local Plans, ensuring compliance with the latest Sequential Testing methodologies.

The NaFRA2-driven updates mark a significant step in improving flood risk management and planning policy. Staying ahead of these changes will help ensure a smoother transition in flood risk assessments and planning processes.