Flood Depth Model for England TL Grid, 2004 1% Annual Chance

Modelled fluvial flood depth data was created for the 1% annual chance of flooding situations in 2004 using the JFlow hydrodynamic model on a 5x5m grid. The Environment Agency produced this data to fill gaps in detailed local modelling for spatial planning flood zone definitions. This dataset covers the TL grid reference (100x100km square) within England.

Use Cases

• Assess broad-scale flood risk for spatial planning based on modelled flood depth extents.
• Compare generalised 2004 flood zones with newer local models based on the described modelling approach.
• Support catchment-scale flood management studies based on the 1% annual chance flood scenario.

Strengths

• Data is modelled on a high-resolution 5x5m grid.
• Coverage is provided for a specific 100x100km Ordnance Survey National Grid reference (TL).

Limitations

• The dataset was created in 2004 and has not been updated; more recent local modelling may supersede it.
• The description explicitly states it is not suitable for identifying individual property flooding or detailed site-specific assessments.
• Column-level documentation is absent; field semantics must be inferred after download.

Provenance

Source

Environment Agency (UK), with spatial data licensed from Centre for Ecology & Hydrology and others.

Collection Method

Created using the JFlow two-dimensional hydrodynamic model.

Time Range

Model created in 2004.

Geography

England, specifically the Ordnance Survey National Grid reference TL (a 100x100km square).