Reservoir Flood Map Maximum Flood Outline Extent
Map Llifogydd sy’n Amlinellu Maint Eithaf Llifogydd o Gronfeydd Dŵr

  • English
  • wel
  • All

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

Identification

Dynodydd
Identifier
NRW_DS116250
Teitl Amgen
Alternative Title
  • AFA113 Reservoir Flood Map Maximum Flood Outline (Extent)
Laith Metadata
Metadata Language
English
Lineage

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.
Additional Information

https://flood-risk-maps.naturalresources.wales/?locale=en

Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
Dataset Reference Date (Publication)
2020-10-27
Perchennog
Owner
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Cychwynnwr
Originator
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 

Extent

Extent

Hyd
Geographic Extent
Wales (WLS)
N
W
E
S
Map representing the geographic extent of the dataset


 
 

Distribution

Fformat - Math a Disgrifiad
Format Type and Description
  • Geographic Information System ( Unknown )

    Specification

    ESRI GIS Format

 

Quality

Ansawdd Data
Data quality

Cwmpas Ansawdd
Quality Scope
Dataset
Dataset
Cydymffurfiad
Conformity
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
Explanation

This dataset has not been assessed for conformance to the referenced INSPIRE regulation.
Degree
false
Lineage

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.
 

Keywords

Allweddair
Keywords

GEMET - INSPIRE themes, version 1.0
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2008-06-01
Code
geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Allweddair
Keywords

NRW Thesaurus
  • Flood management
  • flood risk
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2025-01-08
Code
geonetwork.thesaurus.local.theme.converted_nrw-keywords

Allweddair
Keywords

IPSV Subjects List
  • Reservoirs
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2020-11-18
Code
geonetwork.thesaurus.external.theme.subjects

Allweddair
Keywords

NRW SMNR Keywords
  • 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)
Math
Type
Theme
Theme

Dyfyniad
Citation

Dyddiad (Cyhoeddiad)
Date (Publication)
2024-06-26
Code
geonetwork.thesaurus.local.theme.converted_nrw-smnr-keywords
 

Spatial Reference System

Code
Latitude and Longitude (EPSG::4326)
 

Content

Gwybodaeth Cynnwys
Content Information

Proffil CNC
NRW Profile

Elfennau CNC
Custom Elements

 

Constraints

Constraints

Limitations on Public Access and Use

Math o Gyfyngiad
Restriction type
Other restrictions
Other restrictions
 

Access Constraints Directive

Limitations
no limitations
 

Access Constraints Text

Other constraints

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.
 

Use Constraints

Cyfyngiadau Defnyddio
Use constraints type
Other restrictions
Other restrictions
Other constraints

© CNC/NRW. Data may be re-used under provision and in line with the terms of a NRW licence.
 

Attribution Statement

Other constraints

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

Licence

Other constraints
Third Party Conditional
 
 
 

Metadata

Metadata

Dynodydd Ffeil
File Identifier
4f4c4942-4343-5764-6473-313136323530 XML
Laith Metadata
Metadata Language
English
Math o adnodd
Resource type
Dataset
Dataset
Dyddiad Metadata
Metadata Date
2025-12-19T11:48:52.382Z
Enw Safonol Metadata
Metadata Standard Name
NRW
Fersiwn Metadata
Metadata Standard Version

1.0

Pwynt Cyswllt
pointOfContact
  Natural Resources Wales (NRW) -
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 
 

Publishing Body

Access the portal