Flood Depth Grids for England SW Region, 2004 Generalised Model

JFlow hydrodynamic modelling produced fluvial flood depth data on a 5x5m grid for the 1% annual chance flood scenario. The Environment Agency created this dataset in 2004 to fill gaps in detailed local modelling for spatial planning flood zone definitions. Data covers the Ordnance Survey National Grid reference SW (100x100km) but has not been updated since its creation.

Use Cases

• Assessing broad catchment-scale flood hazard based on modelled flood depth grids.
• Supporting Shoreline Management Plan development using generalised flood extent data.
• Identifying areas for further detailed flood risk studies based on the 2004 model outputs.
• Historical analysis of flood zone definitions used in spatial planning circa 2004.

Strengths

• Data modelled on a high-resolution 5x5m grid.
• Created for a specific flood probability scenario (1% annual chance).
• Covers a defined 100x100km grid square (SW reference).

Limitations

• Dataset has not been updated since 2004; local detailed modelling may supersede it.
• Not suitable for property-level assessment or detailed decision-making as stated in the warning.
• Description metadata is limited; actual data quality requires manual inspection after download.

Provenance

Source

Environment Agency, with data licensed from Centre for Ecology & Hydrology, Defra, Met Office, and others.

Collection Method

Produced using a two-dimensional hydrodynamic model (JFlow) as part of a 2004 generalised modelling project.

Time Range

2004

Geography

Ordnance Survey National Grid reference SW (100x100km square in England).