Flooding rainfall ‘not extraordinary’

MET ÉIREANN said while the rainfall which preceded November’s devastating floods in Cork could be expected to occur every 25 years it could not be described as “extraordinary”.

But the amount of rain which fell in the Shannon River’s catchment area, it said, was exceptional and should only happen once every 500 years. The country’s weather monitoring experts appeared before the Oireachtas Committee on the Environment yesterday and detailed their draft report on last year’s flooding throughout the country.

Liam Keegan, head of its climatology division, brought statistics which he said showed an “extraordinary” amount of rain had fallen in November, on top of three years of heavy rain. He said 79% of its stations reported their highest ever rainfall levels in November.

The graphs produced by Mr Keegan showed much of Connacht, Clare and parts of Ulster experienced 25-day rain patterns that should only occur once every 500 years. However, in Cork the rainfall was not as large and only very isolated, higher altitude areas in West Cork and Kerry were under such pressures. The rest of Cork experienced patterns that should probably happen every 25 years. “In terms of Cork’s rainfall there was heavy rain but you are not using the words extraordinary to describe it. Of itself it does not stand out.”

He said he could not account for all the factors which caused the flooding below the Lee Fields.

In response to questioning from deputies Ciarán Lynch (Lab), Christy O’Sullivan (FF) and Senator Jerry Buttimer (FG), Met Éireann said it had provided a severe weather warning to both Cork local authorities and the ESB. Forecaster Gerald Fleming said these warnings were delivered on November 18 and gave advance notice of high levels of rain but it was up to these agencies to predict the local effects.

Engineer Paudie Barry, of Baseline Surveys, told the committee a report his company produced suggested it was not the volume of rain which fell that caused the flooding, but the amount of water released by the ESB from the Inniscarra Dam. He said a similar downpour in 1986 had been handled differently and 331 cubic millimetres were released every second from the dam. But on November 19 this rose to 535 cubic millimetres.