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Data Provider: Welsh Government Properties at Risk of Flooding
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Year[Filtered]
Area Code[Filter]
Measure1
[Collapse]Risk[Filter]
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[Collapse]Risk 1
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Risk 2
[Collapse]Area[Filter]
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[Collapse]Area 1
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Area 2
[Collapse]TotalClick here to sortTotal
[Expand]Click here to sortMedium + High[Expand]Click here to sortLow[Expand]Click here to sortVery Low
[Collapse]Wales61,108146,1061,336208,550
Wales[Collapse]North Wales12,98743,49476057,241
North WalesIsle of Anglesey1,096521481,665
Gwynedd3,4375,460768,973
Conwy2,12214,36944016,931
Denbighshire3,00812,50411115,623
Flintshire2,3709,3771811,765
Wrexham9541,263672,284
[Collapse]Mid & South West Wales24,11930,07627154,466
Mid & South West WalesPowys7,1365,23220112,569
Ceredigion2,1743,12945,307
Pembrokeshire8641,51312,378
Carmarthenshire7,2497,5223414,805
Swansea3,1362,48445,624
Neath Port Talbot3,56010,1962713,783
[Collapse]South East Wales24,00272,53630596,843
South East WalesBridgend2,5822,342294,953
Vale of Glamorgan1,4281,39702,825
Cardiff2,78032,32021635,316
Rhondda Cynon Taf4,5585,7951010,363
Merthyr Tydfil1,0061,16222,170
Caerphilly2,1934,86367,062
Blaenau Gwent1,57879402,372
Torfaen2,2951,381193,695
Monmouthshire1,7505,54397,302
Newport3,83216,9391420,785

Metadata

Title
Properties at Risk of Flooding in Wales

Last update
January 2017 January 2017

Next update
2019

Publishing organisation
Welsh Government

Source 1
National Flood Risk Assessment data, Natural Resources Wales

Contact email
stats.environment@gov.wales

Designation
None

Lowest level of geographical disaggregation
Local authorities

Geographical coverage
Wales

Languages covered
English only

Data licensing
You may use and re-use this data free of charge in any format or medium, under the terms of the Open Government License - see http://www.nationalarchives.gov.uk/doc/open-government-licence

General description
The National Flood Risk Assessment (NaFRA) together with the National Property Dataset (NPD) are used to determine the number of properties (residential and non-residential) at risk of flooding from rivers and sea in Wales.

Data collection and calculation
The chance of flooding is set out in four risk categories:

High Risk; Greater than or equal to 1 in 30 (3.3%) chance in any given year
Medium Risk; Less than 1 in 30 (3.3%) but greater than or equal to 1 in 100 (1%) chance in any given year
Low Risk; Less than 1 in 100 (1%) but greater than or equal to 1 in 1,000 (0.1%) chance in any given year
Very Low Risk; Less than 1 in 1,000 (0.1%) chance in any given year

The NaFRA includes flooding from all rivers with a catchment size greater than 3 square kilometres, and all flooding from the sea (both along the open coast and tidal estuaries). Smaller rivers are included in the assessment where they fall within the area that could be affected by an extreme flood (0.1% chance in any year).
The assessment takes into account the type, location and condition of flood defences, and the chance of these defences being overtopped or breached during major floods. The likelihood of flooding and the consequent costs (economic damages) are assessed for each 50m square impact zone.
It does not include other forms of flooding such as highway drains, sewers, overland flow or rising groundwater.

Frequency of publication
Annual

Data reference periods
2014 onwards

Rounding applied
None.

Statistical quality
The NaFRA includes flooding from all rivers with a catchment size greater than 3 square kilometres, and all flooding from the sea (both along the open coast and tidal estuaries). Smaller rivers are included in the assessment where they fall within the area that could be affected by an extreme flood (0.1% chance in any year).
The assessment takes into account the type, location and condition of flood defences, and the chance of these defences being overtopped or breached during major floods. The likelihood of flooding and the consequent costs (economic damages) are assessed for each 50m square impact zone.
It does not include other forms of flooding such as highway drains, sewers, overland flow or rising groundwater.

Keywords
Flooding