South Dublin County is susceptible to several types of flood risk. The flood zone extent mappings were prepared and are presented in Appendix A of the Strategic Flood Risk Assessment report developed to support the County Development Plan 2022.

The flood zone maps are primarily derived from the Eastern Catchment Flood Risk Assessment and Management (CFRAM) and the Dodder CFRAM mapping. The maps are the most comprehensive flood maps produced for South Dublin.

Flood extents for areas that are outside of the scope of the CFRAM Studies are supplemented by fluvial (river) mapping from the earlier Office of Public Work Preliminary Flood Risk Assessment (PFRA) Report.

Additionally, pluvial (rainfall) flood extent mapping has been prepared for the 1% and 0.1% Annual Exceedance Probability (AEP) events[1] as derived from the PFRA study.

The Flood Zone mapping is based on the best currently available data. More detailed, site specific Flood Risk Assessments may generate localised flood extents.

[1] Annual Exceedance Probability: The probability, typically expressed as a percentage, of a flood event of a given magnitude being equalled or exceeded in any given year. For example, a 1% AEP flood event has a 1%, or 1 in a 100, chance of occurring or being exceeded in any given year (Source: www.floodinfo.ie).