AfA480: 2004 Climate Change Fluvial Flood Depth Grids for England

A 2004 Environment Agency project produced modelled fluvial flood depth data on a 5x5m grid for a 1% annual chance flood event, simulating a 20% increase in peak flows to assess climate change sensitivity. This high-level national dataset was created using the JFlow hydrodynamic model to fill gaps in detailed local modelling for spatial planning. The data covers all of England but is distributed as 100x100km tiles, such as grid references TR, TM, and TG, and has not been updated since its creation.

Use Cases

• High-level sensitivity analysis of climate change impacts on flood extents based on a simulated 20% peak flow increase.
• Defining approximate Flood Zones for regional spatial planning where detailed local models were unavailable in 2004.
• Assessing broad-scale flood risk patterns under a historical climate change scenario for England.

Strengths

• Provides national coverage for England with a consistent 5x5m spatial resolution.
• Based on a defined two-dimensional hydrodynamic model (JFlow) and a specific climate change scenario (20% peak flow increase).
• Cross-platform presence on uk_data and eu_open_data indicates recognized utility and importance.

Limitations

• The dataset was created in 2004 and has not been updated; climate change allowances and modelling methods have since changed.
• Explicitly not suitable for property-level assessment, detailed decision-making, or site-specific flood risk assessments.
• Metadata for size, row count, license, and specific columns is consistently missing or listed as 'unknown' across all sources.

Provenance

Source

Environment Agency (UK)

Collection Method

Produced as a by-product of the 2004 generalised modelling project using the JFlow two-dimensional hydrodynamic model.

Time Range

2004

Freshness

Metadata records were last updated in July 2026, but the underlying data is from 2004 and is explicitly stated as not updated.

Geography

England, distributed in 100x100km Ordnance Survey National Grid tiles (e.g., TR, TM, TG).