National Flood Hazard Maps for Wales Covering Rivers, Sea, and Surface Water

Wales flood hazard maps for 2019, created to comply with EU Directive 2007/60/EC and the Flood Risk Regulations (2009). The maps model three flooding sources—rivers, the sea, and surface water—showing depth, velocity, hazard, and extent for high, medium, and low risk scenarios. The data was produced by the Government Digital Service based on generalized modeling to inform Flood Risk Management plans.

Use Cases

• Assess regional flood exposure based on modeled hazard and extent for three water sources.
• Compare flood risk scenarios based on defined Annual Exceedance Probability thresholds for rivers, sea, and surface water.
• Inform non-statutory planning and awareness initiatives based on the generalized flood modeling.

Strengths

• Covers three distinct flooding sources: rivers, the sea, and surface water & small watercourses.
• Defines specific risk thresholds (e.g., high risk up to 1 in 30-year AEP for rivers) for structured analysis.
• Includes multiple hazard dimensions: flood depth, velocity (speed and direction), hazard, and extent.

Limitations

• The description explicitly states the maps have no official status for planning or insurance purposes.
• Row count, column details, and file formats are unknown, limiting suitability assessment.
• Last update date is unknown; freshness unverified.

Provenance

Source

Government Digital Service

Collection Method

Generalized modeling based on surface water catchments and other hydrological data.

Time Range

2019

Freshness

2019

Geography

Wales