Does SN13 flood?

Yes — parts of the SN13 district carry real flood risk: 19 of its 23 at-risk postcodes reach the Environment Agency's High likelihood band. The SN13 postcode district covers Box & Colerne, close to Corsham, Ashley, Melksham, and surrounding villages in parts of Wiltshire and Bath and North East Somerset.

23 postcodes in the SN13 district appear in the Environment Agency's rivers-and-sea flood-risk dataset — worst bands: 19 high, 1 medium, 3 low. A postcode not listed here has no properties in any recorded risk band (which is good news, but never proof it cannot flood).

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Which SN13 postcodes are at risk?

Rivers and flooding history near SN13

The rivers that matter here, each monitored live on FloodRadar:

Corsham on the River Avon — 1.1 km away, highest on record 0.89m
Middlehill on the By Brook — 4.5 km away, highest on record 2.41m
Melksham Shaw on the South Brook — 4.7 km away, highest on record 1.71m
Bathford on the River Avon — 7.8 km away, highest on record 4.26m

83 official flood warnings and alerts have been raised within ~10 km of the district's centre since 2006 (83 at warning level or above), most recently 18 December 2025. Warnings cover flood areas, not individual addresses.

Recorded flood extents near the district (Environment Agency record):

This represents flooding in the area in 2014 (2014) — about 1.3 km from the centre
EA112_Avon_April_Flood Event (2012) — about 4.6 km from the centre
This represents flooding in the area in 1990 (1990) — about 1.4 km from the centre
This represents flooding in the area in 1978 (1978) — about 1.6 km from the centre

🏠 Buying or renting in SN13? The full property flood-risk report covers any postcode here — the official likelihood band, every recorded flood nearby with distances, warning history year by year, how the local rivers behave, and an insurance outlook, print-ready for £19. See what's in the report →

Flood risk in nearby postcode districts

SN12 SN14 SN11 SN15 SN10 SN16 SN9 SN8

Band = the worst likelihood band of any property in that postcode (EA Risk of Flooding from Rivers & Sea, defence-adjusted, area-level). Check any postcode in detail — or get the full £19 property report — at the property flood-risk report. © Environment Agency copyright and/or database right 2025. All rights reserved. Some features of this map are based on digital spatial data from the Centre for Ecology & Hydrology, © NERC (CEH). © Crown Copyright and Database Rights 2025 OS AC0000807064. This product is produced in part from PAF® and Multiple Residence Data, the copyright in which is owned by Royal Mail Group Limited and/or Royal Mail Group plc. All rights reserved. Licence number AC0000807064.