UK Surface Water Flood Flow Direction at 0.1% Annual Chance

Environment Agency mapping shows the dominant flow direction of surface water flooding with a 0.1% annual probability, resampled to a 25-meter grid. This dataset is part of the superseded Risk of Flooding from Surface Water (RoFSW) mapping, previously known as the updated Flood Map for Surface Water. The record has been retired and is not suitable for property-level assessment.

Use Cases

• Model regional flood water movement based on dominant flow direction data.
• Assess broad-scale surface water flood risk for strategic planning based on the 0.1% annual chance event.
• Integrate flow direction layers with other geospatial data for composite environmental hazard mapping.

Strengths

• Flow direction is derived from a higher-resolution 2-meter grid source.
• Data is grouped into 8 compass direction bands for categorical analysis.
• Produced by the UK Environment Agency with contributions from multiple authoritative organizations like the Centre for Ecology & Hydrology.

Limitations

• The dataset has been retired and superseded by a newer version.
• Description metadata is limited; actual data quality requires manual inspection after download.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

Environment Agency, UK, with data licensed from the Centre for Ecology & Hydrology (CEH), Defra, Met Office, DARD Rivers Agency, Cranfield University, and James Hutton Institute.

Collection Method

Output from Risk of Flooding from Surface Water (RoFSW) mapping, resampled from a 2m grid.

Freshness

Last updated 2026-07-06 07:17:20.322177; freshness should be verified.

Geography

Likely covers areas within the United Kingdom, as implied by the contributing UK organizations.