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Version: 0.1.0 | Published: 10 Dec 2025 | Updated: 97 days ago

Flood Indicators per LSOA in 2025

Dataset

Summary

Description:
This dataset provides flood risk information for England at the Lower Super Output Area (LSOA) level for 2025. It includes whether each LSOA is at risk of flooding and the surface area at risk within Flood Zone 3, or both Flood Zone 2 and Flood Zone 3. Flood zones are defined as follows: Flood Zone 2 – land with a 0.1% to 1% (1 in 100 to 1 in 1000) annual probability of river flooding, or 0.1% to 0.5% (1 in 200 to 1 in 1000) annual probability of sea flooding, including areas with accepted recorded flood outlines; Flood Zone 3 – areas with a 1% or greater (1 in 100) annual probability of river flooding, or 0.5% or greater (1 in 200) annual probability of sea flooding. The underlying data is provided as a shapefile, indicating areas at risk per LSOA. The dataset is published by the Environment Agency. **IMPORTANT** - This is a beta version of the data product. We have released it as a preview to allow users exploration and experimentation while we perform final quality assurance and additional checks. If you encounter any issue or have questions, please get in touch with us at [imago@liverpool.ac.uk](mailto:imago@liverpool.ac.uk) We will shortly be releasing a more stable version. Please check [https://imago.ac.uk](https://imago.ac.uk) for news and updates.
Contact Point:

Documentation

Documentation:
The dataset contains five flood-related variables for each Lower Super Output Area (LSOA) in England: (1). Dummy_flooded – a binary indicator of whether the LSOA is at risk of flooding. (2). Flooded_area_km2_FZ2and3 – surface area (in km²) at risk within Flood Zone 2 and Flood Zone 3. (3). Flooded_area_km2_FZ3 – surface area (in km²) at risk within Flood Zone 3. (4). Ratio_flooded_FZ3 – proportion of the LSOA area at risk within Flood Zone 3. (5). Ratio_flooded_FZ2_3 – proportion of the LSOA area at risk within Flood Zones 2 and 3. Geographic identifiers include LSOA-equivalent regional codes and names, as well as total LSOA area (total_area_km2). The dataset is provided in two formats: a CSV file containing the tabular data, and a GPKG (GeoPackage) file, which combines the tabular data with LSOA-equivalent boundary geometries for spatial analysis.

Coverage

Spatial

Spatial Coverage:
United Kingdom
Geographical Levels:
MSOA

Temporal

Start Date:
⁠Annual: 01-01-2025:31-12-2025
Frequency:
Annual
Date of Latest Release:
10 December 2025
Date of First Release:
10 December 2025

Provenance

Origin

Purpose:
The flood zone data is provided by the Environment Agency and represents a composite of national and local flood model outputs, recorded flood outlines, and information from past flood events. These sources are combined using the National Flood Risk Assessment (NaFRA2) system to generate the best-available extents of land at risk of flooding. The Flood Zones are intended to support planning applications and inform whether a Flood Risk Assessment (FRA) and the sequential test may be required. Users should note that the Flood Zones indicate general flood risk for an area of land and are not suitable for assessing flood risk for individual properties, as property-specific details are not included. Users are advised to confirm that the dataset is appropriate for their intended use. **IMPORTANT** - This version is released as beta. This means that, although we have applied our quality standard in its production, we are still assessing its overall quality and identifying minor issues that need resolution before a more stable version can be released. As soon as we are ready, we will issue a new release. Please check https://imago.ac.uk for news and updates.
Source:
The underlying data source is the Environment Agency Flood Map for Planning – Flood Zones dataset, which provides information on the extent of land at present-day risk of flooding from rivers and the sea, excluding the benefits of flood defences. The dataset is described in: https://environment.data.gov.uk/dataset/04532375-a198-476e-985e-0579a0a11b47. Flood risk areas were classified according to Flood Zone 2 and Flood Zone 3 criteria. The LSOA-level aggregation was performed by the Imago Team by calculating the surface area at risk and deriving ratios relative to total LSOA area, producing variables for flood presence (dummy_flooded), flooded area in km² (flooded_area_km2_FZ3 and flooded_area_km2_FZ2and3), and proportional coverage of each LSOA.
Collection Status:
0.1.0

Author 1

Name Organisation:
Imago: Data Service for Imagery
Family Name Person:
Elisabetta Pietrostefani

Access and Governance

Usage

Data Use Requirements:
None

Access

Access Rights:
CC-BY-NC-4.0
Licence:
CC-BY-NC-4.0

Format and Standards

Vocabulary Encoding Scheme:
EPSG:27700, OSGB36/British National Grid