4f4c4942-4343-5764-6473-313136323530 English Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en 2025-12-19T11:48:52.382Z NRW 1.0 wel Latitude and Longitude (EPSG::4326) Reservoir Flood Map Maximum Flood Outline Extent Reservoir Flood Map Maximum Flood Outline Extent Map Llifogydd sy’n Amlinellu Maint Eithaf Llifogydd o Gronfeydd Dŵr AFA113 Reservoir Flood Map Maximum Flood Outline (Extent) 2020-10-27 NRW_DS116250 Data layer showing individual reservoir flood maps for 225 Large Raised Reservoirs including attributed data. Individual reservoirs may have up to 5 flood maps associated with them, based on separate breach locations. The data shows the maximum extent of flood should the reservoir be breached, although the location of the reservoir can be inferred it is not explicitly shown on the maps. Reservoir flooding is extremely unlikely to happen. There has been no loss of life in the UK from reservoir flooding since 1925. All large reservoirs must be inspected and supervised by reservoir panel engineers. As the enforcement authority for the Reservoirs Act 1975 in Wales, we ensure that reservoirs are inspected regularly and essential safety work is carried out. An online viewable version of this dataset is available here: https://flood-risk-maps.naturalresources.wales/?locale=en Data layer showing individual reservoir flood maps for 225 Large Raised Reservoirs including attributed data. Individual reservoirs may have up to 5 flood maps associated with them, based on separate breach locations. The data shows the maximum extent of flood should the reservoir be breached, although the location of the reservoir can be inferred it is not explicitly shown on the maps. Reservoir flooding is extremely unlikely to happen. There has been no loss of life in the UK from reservoir flooding since 1925. All large reservoirs must be inspected and supervised by reservoir panel engineers. As the enforcement authority for the Reservoirs Act 1975 in Wales, we ensure that reservoirs are inspected regularly and essential safety work is carried out. An online viewable version of this dataset is available here: https://flood-risk-maps.naturalresources.wales/?locale=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural risk zones Hydrography GEMET - INSPIRE themes, version 1.0 2008-06-01 geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme Flood management flood risk NRW Thesaurus 2025-01-08 geonetwork.thesaurus.local.theme.converted_nrw-keywords Reservoirs IPSV Subjects List 2020-11-18 geonetwork.thesaurus.external.theme.subjects Water Resources (SMNR) Soil and Land (SMNR) Freshwater and Wetlands (SMNR) Flooding (SMNR) Management Areas (SMNR) Natural Resources (Incl. Features and Processes) (SMNR) Sustainable Management of Natural Resources (SMNR) Ecosystem (SMNR) NRW SMNR Keywords 2024-06-26 geonetwork.thesaurus.local.theme.converted_nrw-smnr-keywords Part of this dataset is sensitive and restricted as it contains data exempt from general release under EIR. Sensitive data must be kept confidential; general release is not permitted due to national security reasons. no limitations © CNC/NRW. Data may be re-used under provision and in line with the terms of a NRW licence. Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved. Third Party Conditional English environment SeaVoX Vertical Co-ordinate Coverages 2021-01-06 Wales (WLS) -5.777741 -2.608865 51.240829 53.513067 2013-04-01 2013-04-01 https://flood-risk-maps.naturalresources.wales/?locale=en Geographic Information System Unknown ESRI GIS Format Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 This dataset has not been assessed for conformance to the referenced INSPIRE regulation. false The Reservoir Flood Map Outline (Extent) shows the largest area that might be flooded if a reservoir were to fail and release the water it holds. Since this is a prediction of a credible worst case scenario, it’s unlikely that any actual flood would be this large. These data are intended for emergency planning only and are not reliable for large scale flood risk assessments. Please note that only flood maps for large reservoirs are displayed. Flood maps are not displayed for smaller reservoirs or for reservoirs commissioned after reservoir mapping began in spring 2009. The Reservoir Flood Map Outline (Extent) shows the largest area that might be flooded if a reservoir were to fail and release the water it holds. Since this is a prediction of a credible worst case scenario, it’s unlikely that any actual flood would be this large. These data are intended for emergency planning only and are not reliable for large scale flood risk assessments. Please note that only flood maps for large reservoirs are displayed. Flood maps are not displayed for smaller reservoirs or for reservoirs commissioned after reservoir mapping began in spring 2009.