dataset · England
Rivers and Sea defended and undefended flood risk extents - present day
These datasets show the extent of land at risk of flooding to a defined annual exceedance probability (AEP) or chance of flooding each year. These scenarios show a present day risk; climate change scenarios are available separately. These datasets include the following scenarios: ● Undefended: 0.1% AEP (1 in 1000) Rivers/Sea ● Undefended: 1% AEP (1 in 100) Rivers/ 0.5% AEP (1 in 200) Sea ● Defended: 0.1% AEP (1 in 1000) Rivers/Sea ● Defended: 1% AEP (1 in 100) Rivers/ 0.5% AEP (1 in 200) Sea The
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Licence: ["There are no public access constraints to this data. Use of this data is subject to the licence identified.", "There are no public access constraints to this data. Use of this data is subject to the
Evidence quality: 57.2
Listed in data.gov.uk public catalogue API on 2026-10-16; relevance/value screened (haiku).
Metadata checked: 2026-10-14T13:20:00.000Z
What's in it
- Data offered docs-verified
- flood extent: undefended 0.1% AEP (1 in 1000) rivers/sea · flood extent: undefended 1% AEP (1 in 100) rivers / 0.5% AEP (1 in 200) sea · flood extent: defended 0.1% AEP (1 in 1000) rivers/sea · flood extent: defended 1% AEP (1 in 100) rivers / 0.5% AEP (1 in 200) sea
- Coverage docs-verified
- England (extent 49.943°N to 55.816°N, 6.236°W to 2.072°E) · present day scenario only; no historical time span stated
- Update frequency docs-verified
- as needed (no fixed schedule)
- Formats docs-verified
- OGC API - Features · WFS · WMS · GeoJSON (zipped) · File Geodatabase (zipped) · ArcGIS .lyr layer files · PDF product description
- Access docs-verified
- free/open; Open Government Licence v3.0; no public access constraints; no authentication
Useful for
- Use cases llm-inferred
- FRA screening: identify whether a site lies within the 1 in 100 or 1 in 1000 rivers/sea flood extent · Planning and sequential-test screening of development sites against present-day flood extents · Comparing defended and undefended extents to show the residual risk that flood defences provide · Preliminary flood-risk context for a drainage or civils scheme before detailed modelling
- Audience llm-inferred
- flood consultants · drainage engineers · hydrologists · planners · GIS analysts
Limitations
- Constraints docs-verified
- indicative only: not suitable for showing whether an individual property is at risk of flooding · present day scenarios only; climate change scenarios are separate datasets · no flood depth, speed or volume of flow information · defended products do not include asset failure or removal scenarios · users must check suitability for their intended use
Evidence
- https://environment.data.gov.uk/api/file/download?fileDataSetId=2bd9e146-ec42-4453-878d-ba9a95d7543f&fileName=Rivers and Sea Defended and Undefended Product Description.pdf
- https://www.data.gov.uk/dataset/1589b7ec-2300-4028-9199-aa7cac4b0f68/rivers-and-sea-defended-and-undefended-flood-risk-extents-present-day
Check upstream coverage, uncertainty and licence before use. Station observations are not forecasts or design levels.