No easy solutions to flooding in the west
Published 20/04/2016 | 02:30
The floods that hit many farms in the West last winter made compelling viewing on the TV news at that time. There is nothing however to compare with seeing something at first hand and when in Kinvara recently, a friend took me on a tour of some of the worst affected areas around Ardrahan in Co Galway.
This was in early April and it was astonishing to see how much water still remained.
Looking at the dark lines that reached over the windowsills on some buildings and the muddy areas still covering entire fields, I could clearly see the extent of the damage and the farmland that had been drowned during the height of the rainfall.
The turloughs were still almost full and it was difficult to imagine them ever draining, as of course they will later in the year when livestock can again graze on the enriched grassland.
But for now the aftermath of the devastation was all too clear and while turloughs have always filled over the winter months, the recent floodwaters reached heights never before encountered.
Turloughs are a type of disappearing lake and are a feature almost unique to Ireland. Principally associated with the limestone areas that occur in Roscommon, Galway, Mayo and Clare, they are essentially grassy hollows, often extending over many acres which, during wet weather, fill with water through subterranean passages in the rock, and empty by the same means.
The duration and frequency of the flooding varies from turlough to turlough and all are dependent on underground drainage. Most flood in the autumn, usually sometime in October and then dry up between April and July.
However, some turloughs in the Burren can flood at any time of year in a matter of a few hours after heavy rainfall and may then empty again a few days later. They usually fill and empty at particular places on the lake floor and sometimes a hole or passage is visible but more often a hollow with stones in the bottom is all that can be seen.
Some turloughs have a spring at one place and a swallow hole leading to an underground cave system in another location where water can drain away, while many fill and empty through the same hole.
In the past flooding has been blamed on these swallow holes getting blocked by material such as the shreds of torn black plastic from silage bales that can be seen hanging from roadside hedgerows throughout Ireland. In the Burren this plastic has been given the colourful name of "witches knickers".
One can well imagine a witch flying along at high speed on her broomstick and when swerving through a hedge, having items of her clothing torn and left hanging on the thorny branches!
Up to now, some of the work carried out to alleviate flooding appears to have been counterproductive. Water sinking in a swallow hole travels underground to re-emerge at a spring which can be several kilometres away and draining one area affects the next and so on down to the sea.
It must be remembered that while much of the water in the areas I visited exits to the sea at Dunguaire Castle beside Kinvara, it also exits initially into vast underground caves, many of which have yet to be explored and about which little is known.
One man I spoke to said that he believed that the drainage works that took place in an attempt to lessen the flooding around Gort had then impacted on Cahermore turlough and greatly increased the flooding there this year.
It would appear that if you drain one area, you simply send the problem on to the next spot down the line.
Many home and business owners are already preparing flood defences for next winter but no one can tell how effective they will be.
At Justin Flannery's abattoir at Peterswell, flooding reached right in to the yard of the premises. The turlough adjoining his property still looked vast and currently covers around 300ha but it too will disappear over the coming months.
As I drove around the area, some roads were still closed to traffic but extensive works are now taking place to raise the level of other roads in the locality. This will hopefully allow for better traffic movement but will not protect houses in the endangered areas. There are no easy answers and if our winter rainfall continues to increase, vulnerable homeowners face an uncertain future and could well be forced to relocate.