BN7 flood risk: Lewes
The representative point is not in a higher-risk flood zone (Zone 1)
At the representative point for Lewes (BN7), the Environment Agency does not record a medium- or high-risk flood zone (Zone 1, below a 1-in-1,000 annual chance from rivers). Risk still varies street by street, and surface-water flooding can affect Zone 1 land — check the exact address.
Ouse valley town devastated by the 2000 floods.
Flood zone band
Below a 1-in-1,000 annual chance from rivers/sea.
1-in-100 to 1-in-1,000 annual chance from rivers.
1-in-100 or greater from rivers; 1-in-200 from the sea.
Recorded flood history nearby
The Environment Agency has 4 recorded flood outlines within ~250 m of the representative point for BN7:
- Winter 13/14 East Hampshire Aerial Photography5 Mar 2014 · fluvial
- 07421J601FEO_Jan2009_LowerOuse_Lewes22 Jan 2009 – 24 Jan 2009 · fluvial
- 07421J601FEO_OCT2000_Ouse_BarcombeMills12 Oct 2000 – 14 Oct 2000 · fluvial
- 07421J601FEO_NOV1960_Ouse_Lewes1 Nov 1960 · fluvial
Ask the seller to confirm the property's flood history on the TA6 Property Information Form.
Climate-change river-flow uplift
Management catchment: Adur and Ouse (South East). Projected % uplift to peak river flow vs the 1961–1990 baseline (river flooding only):
| Epoch | Central (50%) | Higher central (70%) | Upper end (95%) |
|---|---|---|---|
| 2020s | +16% | +23% | +40% |
| 2050s | +18% | +28% | +57% |
| 2080s | +37% | +55% | +107% |
River (fluvial) flooding only — says nothing about surface-water or tidal change.
What this means for buyers and insurance
Flood zones are mapped at street level — an outcode is too coarse to decide on a single property. A home a few metres from a Zone 3 boundary can be Zone 1, and vice versa. Treat this page as the area context, then check the exact address.
In Zone 2 or 3, factor in: a possible lender requirement for a flood report, higher insurance premiums (the Flood Re scheme caps eligible UK homes' premiums but is legislated to end in 2039), and the seller's legal duty to disclose flood history on the TA6 form.
Check a specific BN7 address
This page covers the BN7 area. To see river, surface-water and coastal flood risk, recorded flood history and climate projections for one exact address, run the free flood-risk tool — the full analysis is included in the £24.99 Complete report.
Frequently asked questions
Is BN7 in a flood zone?
The representative point for BN7 (Lewes) sits in Flood Zone 1 (low river-flooding risk). Individual streets can still differ, and surface-water (flash) flooding is mapped separately, so always check the specific address.
What do the flood zones mean for buying a house?
Flood Zone 1 is low risk (below a 1-in-1,000 annual chance of river flooding). Zone 2 is medium (1-in-100 to 1-in-1,000). Zone 3 is high (1-in-100 or greater from rivers, or 1-in-200 from the sea). A home in Zone 2 or 3 can be harder to insure and mortgage, and you should ask the seller about flood history on the TA6 Property Information Form.
Does a flood zone affect insurance and mortgages?
It can. Lenders may require a flood-risk report, and premiums rise with risk. The Flood Re scheme caps premiums on eligible UK homes (broadly houses built before 2009, in council-tax bands A–H) but is legislated to end in 2039. Always get an insurance quote on the specific address before committing.
How do I check flood risk for a specific BN7 address?
Flood risk is mapped to individual properties, not whole outcodes. Use the HouseCheckup flood-risk tool to check any address against Environment Agency river, surface-water and coastal data, recorded flood history and climate projections — the full breakdown is included in the £24.99 Complete report.
Sources
- Long-term flood risk check — Environment Agency / GOV.UK
- Flood Map for Planning (flood-risk-zone) — planning.data.gov.uk
- Outcode geocoding — postcodes.io
Flood data © Environment Agency copyright and/or database right 2026 (OGL v3.0). Flood Re eligibility based on floodre.co.uk criteria — indicative only; insurers make final decisions.