floodchecker

POSTCODES IN DN11

849 postcodes checked

Low river/sea risk
Flood Zone 3
1.2% · 10
Flood Zone 2
0.4% · 3
Flood Zone 1
98% · 836

Rivers and the sea, Environment Agency Flood Map for Planning. Counts postcodes, not homes.

Flood risk in DN11 (New Rossington and Rossington)

Of the 849 postcodes in DN11 – covering New Rossington and Rossington, Harworth and Bircotes and Tickhill – 10 (1.2%) have their centre in Flood Zone 3 and 3 (0.4%) in Flood Zone 2, on the Environment Agency’s Flood Map for Planning.

The Zone 3 share is well below the England average of 5.6%, and well below the South Yorkshire figure of 4.9%.

Most of the district is in Flood Zone 1, but the postcodes in Zones 2 and 3 tend to cluster along rivers, streams and low-lying ground – so it’s worth checking the exact postcode rather than relying on the district picture.

Flood zones only cover rivers and the sea, and ignore flood defences. Surface water from heavy rain can affect any street, including in Zone 1.

Flood zones by postcode sector

Each sector is the first part of the postcode plus the first digit after the space. DN11 0 has the highest share in Flood Zone 3 (1.5% of its postcodes).

Postcodes in Flood Zones 2 and 3, by postcode sector in DN11
SectorPostcodesZone 3Zone 2
DN11 03421.5%0.9%
DN11 82781.1%0%
DN11 92290.9%0%

Main rivers in South Yorkshire

  • River Don – Sheffield, Rotherham, Doncaster and Fishlake

  • River Sheaf – Central Sheffield

  • River Rother – Joins the Don in Rotherham

More on the area in our South Yorkshire flood risk guide.

How these figures are worked out

We took the centre point of every live postcode in DN11 from OS Code-Point Open and tested it against the Environment Agency’s Flood Map for Planning, as published in the flood-risk-zone dataset (version of 5 November 2026). A postcode counts once, whether it has one home or forty, and a postcode whose centre is just outside a zone still counts as Zone 1. Updated November 2026.

For one address, the free postcode check looks at the zones around the postcode, and the full report adds surface water, reservoirs, recorded floods and defences.

FAQ

DN11 flood questions

Parts of it are. 1.2% of postcodes in DN11 are in Flood Zone 3 and 0.4% in Flood Zone 2. The rest is in Flood Zone 1. Check your full postcode to see the zone around your street.

Check a DN11 postcode

Free postcode check. Full property report from £17.99.