PARTS of the south west including Limerick city could soon be at risk of severe flooding unless radical proposals to counteract the effects of climate change are introduced soon. While a predicted rise in winter storms is expected to leave previously unaffected areas of the country prone to flooding, some experts say methods currently used to counteract the problem, particularly the construction of flood barriers, are costly, outmoded and ineffective. And it has been claimed that politicians lack the political will to take the unpopular decisions necessary to avoid the growing threat of widespread seasonal flooding.
A recent Met Eireann report on global warming predicts an "an elevated risk of flooding", particularly in the southwest of the country.
According to Ian Lumley, heritage officer with An Taisce, the anticipated rise in rainfall in the north of country will exacerbate flooding further south. "If you have more concentrated periods of heavy rainfall that will ultimately filter down the Shannon basin, and Limerick and other locations are going to be facing flood risks that they didn't previously have."
He believes flood barriers planned for vulnerable urban areas including are potentially dangerous, and ultimately ineffective. "The more you rely on heavy engineering solutions such as embankments or walls, the greater the risk of something going wrong."
Speeding Up Water Flow Lumley claims consultants employed by developers to assess the impact of building on a flood plain will always produce a report endorsing the client's proposals. "The consultant will always propose raising the ground level of the client s property. The fact is, if you raise the ground level to accommodate a retail development or housing you have a knock on effect both upstream and downstream. You are impeding the down water river flow by causing a tailback above your site and at the same time you are speeding up the water flow to the land downstream."
A further problem, Lumley claims, is that consultants are working with what is now out of date data. "Consultants make projections based on what s referred to as a 100year event. They look at the highest recorded flood levels over the last century. What they're not making allowance for is the fact that past data is no longer relevant because we're into a changed situation as far as calculating future flooding is concerned. What we need is a proper national flood map."
According to Tony Lowes of the Friends of the Irish Environment conservation group, environmental impact assessments (EIAs) consistently underestimate the impact of proposed commercial development on flood plain land. "If you put two or three Tescos dotted along a river and they're on the edge of a flood plain, every time you do that people living downstream are going to face more intense onslaughts of water. But if you look at the EIA it will claim the development is on a very small area of the flood plain and it's not going to have that much of an impact. But the fact that you're reducing the area of land mass capable of absorbing water and at the same time you're speeding up the flow, it's inevitable that people in other areas will suffer the consequences."
Audacious Solution Lumley's solution is radical and probably too controversial to win public support or the backing of local authorities.
"If you're really serious about protecting towns like Clonmel and Carrick you need to build weirs upstream and use them to stop the surge of water by allowing agricultural land to be flooded. Obviously this would be a highly controversial solution and issues of compensation would arise.
"The problem is that for 70 years it's been state policy to actually prevent that happening. The OPW and Teagasc have been working to maximise the use of flood plain land in river valleys. So there is less and less land actually capable of absorbing flood and that exacerbates the downward surge of water running through urban centres."
"Drainage is going on at pace around the country with no regard for the fact we need tracts of soggy land as it acts like a sponge absorbing excess water, " Lowes says. "Bord na Mona has been doing this to our bogs for decades. At this stage, the obsession with draining the Shannon has become part of the Irish psyche."
Lowes points to the demolition of the Ballymun towers as a good example of how urban sprawl contributes to the problem of flooding in builtup areas. "Ballymun is already prone to flooding because the drainage system which was put in place in the 19th century consists of piping that's no more than a metre wide. By replacing the high-rise towers with houses the city council has more than doubled the covered-over surface area in the locality. They've diminished the ability of the ground to absorb water and they've also increased the speed at which the water will flood."
Insurance Hike Commercial and residential property owners are already paying higher insurance premiums on buildings located in what are regarded as high risk areas. "There are areas of the country which attract a specific loading from the insurance companies for flood risk, " says Conor Faughnan of AA Insurance. "It's worth pointing out though that there have been fewer severe flooding incidents in the last couple of years than there were in 2005 and for a few years prior to that. Everyone accepts that climate change is real, but the symptoms of it are rather flukey and unpredictable."
The OPW has launched a website (www. flooding. ie) where historic and predictive information can be viewed and it also offers practical advice for householders whose properties have suffered flooding. It also includes suggested draft guidelines on flood risk management for consideration by local authorities.
"We see it as an anomaly that the department of the environment is promoting strategic planning while the OPW is responsible for flood management. The two should be integrated, " says Lumley.
"The truth is there are vested interests opposing the radical solutions that need to be implemented. Unfortunately there is no political appetite to take those interests on. There is no obvious evidence of the national leadership that's required on the issue."
Sunday Tribune
www.buckplanning.ie
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