Surface Water Flood Flow Speed for a 0.1% Annual Chance Event

A retired GIS layer from the UK Environment Agency showing the speed of flood flow from surface water for a 0.1% annual chance event, with speeds grouped into 5 bands. The data is part of the Risk of Flooding from Surface Water (RoFSW) mapping, previously known as the updated Flood Map for Surface Water. It is based on digital spatial data from multiple UK government and research bodies, including the Centre for Ecology & Hydrology and the Ordnance Survey.

Use Cases

• Assess regional surface water flood flow patterns based on the 0.1% annual chance event model.
• Model potential flood hazard zones based on the five speed bands of flood flow.
• Inform strategic planning decisions based on indicative flood risk mapping, when supported by further studies.

Strengths

• Data is derived from multiple authoritative UK sources, including the Environment Agency and the Centre for Ecology & Hydrology.
• Flood flow speed is categorized into five distinct bands for analysis.
• The dataset is part of a formal mapping suite (Risk of Flooding from Surface Water) with documented usage guidance.

Limitations

• The record has been retired and superseded by another dataset.
• Description metadata is limited; actual data quality requires manual inspection after download.
• Column-level documentation is absent; field semantics must be inferred after download.

Provenance

Source

UK Environment Agency, Centre for Ecology & Hydrology (NERC), Ordnance Survey, and other UK government and research bodies.

Collection Method

Produced as part of the Risk of Flooding from Surface Water (RoFSW) mapping program.

Time Range

Data copyright and database right is noted as 2015.

Freshness

Last update date is unknown; freshness unverified.

Geography

Likely covers England, given the source agencies, but specific coverage is not stated.