The National Flood Asset Database records flood infrastructure in Wales managed by Lead Local Flood Authorities (LLFAs) and Natural Resources Wales (NRW). It includes many embankments, walls, flood gates, culverts, and inlet screens (which catch debris), but not all flood infrastructure maintained or owned by these parties. This infrastructure has been constructed to help manage the risk of flooding from rivers and the sea. They do not remove the risk of flooding and can be overtopped, blocked, or fail in extreme weather conditions. Three datasets are available as open data.

  1. Flood defence Locations. These show the linear alignment of flood defence asset that have been built to protect against flooding from rivers and the sea. It includes the type, length, maintainer, and an ID. These defence locations are also shown in Flood Risk Assessment Wales (FRAW), Flood Map for Planning (FMfP) and Find flood defence structures near you maps. They may relate to an Area Benefiting from Flood Defence (FRAW) and TAN15 zone (FMfP).
  2. Culverts (Polyline); These show an indicative location of underground culverts for general guidance only. Attributes include maintainer, owner, length and ID. Due to the underground nature and history of many culverts, the locations may not be accurate, complete, or up to date.
  3. Culvert openings and Screens (Points). These show an indicative location of culvert openings and screens (often referred to as Trash or Debris Screens). Attributes include maintainer, owner and ID. Locations and details may not be accurate, complete or up to date.

We will regularly update the information when new and improved data becomes available. If you have any queries or concerns about location, maintenance, condition, or records of flood assets, check with the owner or maintainer.

This dataset is based on the geographical location of flood assets in Wales and stems from measures 6, 7 and 8 of the National Flood Strategy that aims to bring this data together and make it publicly accessible. The data is taken from asset management systems managed by Natural Resources Wales and the following Lead Local Flood Authorities.

Blaenau Gwent CBC

Bridgend CBC

Caerphilly CBC

Cardiff Council

Carmarthenshire CC

Ceredigion CC

City & County of Swansea

Conwy CBC

Denbighshire CBC

Flintshire CC

Gwynedd Council

Isle of Anglesey CC

Merthyr Tydfil CBC

Monmouthshire CC

Neath-Port talbot CBC

Newport CC

Pembrokeshire CC

Powys CC

Rhondda cynon Taff CBC

Torfaen CBC

Vale of Glamorgan Council

Wrexham CBC

The position of flood assets is for general guidance only. It does not show all flood assets or any coastal erosion/ protection managed by these bodies. Some of the data may be inaccurate or out-of-date Some of the underground assets might not be known or recorded accurately. If you have any queries or concerns about location, maintenance, condition or records of flood assets, check with the owner or maintainer.

Attribution Statement

Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved. © Welsh Local Authorities.

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Please refer to the licence to understand the conditions of using this data.

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Spatial data (3)

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  • nrw_culverts

  • nrw_flood_defence_locations

  • nrw_culverts_and_screens

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