England Flood Depth Grids for 1% Annual Chance, SD Grid Reference 2004

Modelled fluvial flood depth data was created for the 1% annual chance of flooding situations as a by-product from the 2004 generalised modelling project. The Environment Agency produced this data using the JFlow two-dimensional hydrodynamic model on a 5x5m grid to fill gaps where no detailed local modelled data existed in 2004. This dataset covers the 100x100km Ordnance Survey National Grid reference SD.

Use Cases

• Assessing broad catchment-scale flood risk based on modelled flood depth data.
• Supporting Shoreline Management Plan development based on generalised flood extents.
• Historical comparison of flood zones for spatial planning based on 2004 modelling.
• Identifying areas lacking detailed local flood models based on the generalised modelling purpose.

Strengths

• Data is modelled on a 5x5m grid, suggesting high spatial resolution.
• Coverage is for the entire 100x100km Ordnance Survey National Grid reference SD.
• Created using a two-dimensional hydrodynamic model (JFlow), indicating a sophisticated modelling approach.

Limitations

• The dataset has not been updated since 2004 and may be outdated.
• Description metadata is limited; actual data quality requires manual inspection after download.
• The data is explicitly not suitable for identifying whether an individual property will flood or for detailed decision making.

Provenance

Source

Environment Agency

Collection Method

Created using the JFlow two-dimensional hydrodynamic model.

Time Range

2004

Geography

England, specifically the Ordnance Survey National Grid reference SD.