Introduction
The Historical Flood Events map service is a multi layered dataset which shows known areas that have been inundated by flood water in the past. These flooded area outlines have been generated from archived field data and aerial photographs that were collected by Rivers Agency at the time of the actual flood events. In all, over 60 separate events are recorded going back to 1971. The following layers are included:
• Historical Flood Outlines
• Locations of Aerial Photographs indicating flooding
Purpose of the data
The data is used to understand where flooding has occurred in the past and to provide records of the details.
Absence of an historic flood event outline for an area does not mean that the area has never flooded, only that the Rivers Agency does not currently have records of flooding in this area.
Similarly, the inclusion of a record of a flood event outline does not necessarily mean that the area will flood again. Flood alleviation schemes will have been undertaken at some of the flood prone locations and this work will have significantly reduced the likelihood of future flooding at these areas
Data Coverage
All of Northern Ireland, and some limited coverage in Republic of Ireland in border areas.
Data Format
OGC (Open Geospatial Consortium) compliant Web Mapping Service in WGS 1984 projection, accessible via secure website (requires authentication by user specific username and password)..
Data content
Historical Flood Outline
• the spatial outline
• flood event code
• the outline code
• names of the event outline
• start and end dates
• flood extent source
• source and cause of flooding
• flags indicating if the flood was River, coastal, surface water, out of sewer
Aerial Photographs
• the spatial outline
• Comments
• Direction
• Event Date
• Photo Reason
• River Name