DN31 flood risk: Grimsby
Yes — part of this area is in Flood Zone 3 (high risk)
Grimsby (DN31) includes land in Environment Agency Flood Zone 3 — a 1-in-100 or greater annual chance of river flooding, or 1-in-200 or greater from the sea. Flood risk varies street by street within an outcode, so a specific-address check is essential before you offer.
Humber estuary port at tidal-flood risk.
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.
Mapped flood types at the representative point: Tidal Models.
Recorded flood history nearby
The Environment Agency has 5 recorded flood outlines within ~250 m of the representative point for DN31:
- 2020 February Flood Incident - Storm Dennis15 Feb 2020 – 19 Mar 2020 · fluvial
- 2020 February Flood Incident - Storm Ciara8 Feb 2020 – 14 Feb 2020
- 2019 November Flood Incident7 Nov 2019 – 8 Nov 2019
- LNA_2013_12_Tidal_Witham_Haven5 Dec 2013 · tidal
- LNA_1953_01_Lincolnshire Coastline31 Jan 1953 – 1 Feb 1953 · tidal
Ask the seller to confirm the property's flood history on the TA6 Property Information Form.
Climate-change river-flow uplift
Management catchment: Louth Grimsby and Ancholme (Humber). Projected % uplift to peak river flow vs the 1961–1990 baseline (river flooding only):
| Epoch | Central (50%) | Higher central (70%) | Upper end (95%) |
|---|---|---|---|
| 2020s | +4% | +9% | +21% |
| 2050s | +-1% | +5% | +19% |
| 2080s | +4% | +12% | +33% |
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 DN31 address
This page covers the DN31 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 DN31 in a flood zone?
Part of DN31 (Grimsby) is in Environment Agency Flood Zone 3, the highest-risk band, meaning a 1-in-100 or greater annual chance of river flooding. Not every property in the outcode is affected — flood zones are mapped at street level, so you must 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 DN31 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.