MANY findings in a major study aimed at solving Dublin's flood problems are already out of date, city chiefs have admitted.
The €10m Greater Dublin Strategic Drainage Study, produced in 2005, did not envisage the periods of monster rain that have hit the capital in the past couple of years.
The document provides a blueprint for sustainable development in the region, minimising the risk of flooding in the four Dublin local authorities, as well as Meath, Kildare and Wicklow.
But city officials admit the "landscape" has changed since 2005, after which the country has often experienced monsoon-type weather conditions.
The most striking example was last October 24, when more than 100mm of rain fell over a period of 24 hours, washing out thousands of properties in Dublin and Wicklow.
The Dodder burst its banks, flooding nearby homes. The Slang washed out a section of Dundrum town centre.
Among the recommendations of the 2005 study was that new practices be implemented by developers so the drainage system would not be overloaded in times of very heavy rain.
However, the document did not foresee downpours more associated with tropical climates.
"The landscape has changed since 2005, especially with regard to type of rainfall that we have at the moment," executive manager with the city council, Pat Cronin, said.
The new reality is characterised by pluvial rainfall events, commonly referred to as monster rain, he added.
Since 2005, there has been a "very noticeable change" in the type of downpours hitting Ireland, he told a meeting of the city's central area committee.
The recommendations in the strategic study were very valid seven years ago, but they are "not going to necessarily solve the problem" now, according to Mr Cronin.
Dublin City Council is constant contact with Met Eireann over extreme weather events. Officials have access to the forecasting organisation's radar information.