Moving mountains — the dangers of our changing rainfall
FLOODING and landslides are set to become an increasing part of life in
Ireland, according to meteorologists and experts who have been predicting the effects of the climate change we are now seeing.
Inside the last month, people living in towns such as Carlow, Newcastle West, Mallow and Fermoy experienced the misery caused by flooding. August 2008 will also be remembered for flooding in Dublin, even in streets around Croke Park, and the month the Port Tunnel became inaccessible.
Landslides are also caused by incessant downpours and the latest of several examples in recent years occurred in the Kielduff area, outside Tralee, Co Kerry, at the weekend, with serious disruption to public water supplies sourced from affected rivers.
But not all flooding and landslides result from natural phenomena. Human activity is also a key contributor.
Building in flood plains during the Celtic Tiger era, not to mention more volumes of water running off hard tarmac and concrete surfaces in new shopping malls, roads and housing estates, has also led to flooding.
The construction of windfarms in elevated, moorland areas has been blamed for creating conditions that lead to landslides. The building of roads into remote wind farm sites has undermined the soil structure that supports the bog fabric, it has been claimed.
A new report says the risk of landslides in Ireland is greater than was previously thought. The report, by a team from universities and state agencies, says climate change, growing urbanisation and increased infrastructure projects are the root of the problem.
There are records of landslides in Ireland from the 19th century, but it took two key events in 2003, to again heighten awareness of the issue.
People in Derrybrien, Co Galway, and Pollathomas, Co Mayo, were shocked by the destructive power of landslides in their areas that resulted in millions of euro worth of damage.
Forty houses had to be evacuated at Pollathomas where damage was estimated at 10 million.
Responding to the 2003 events, the Geological Society of Ireland (GSI), visited Co Mayo, compiled a brief report on what happened and began a wider study of landslides in Ireland.
A feature common to landslides is that they follow periods of heavy rain that destabilises the surface and lubricates earth movements, making for an easy flow of peat down the valley of a hillside river, or stream.
The north Kerry landslide, described yesterday by senior Kerry County Council engineer Brian Sweeney as the “worst natural disaster in Kerry in 30 years”, occurred in such conditions, on Saturday.
The Stacks Mountains area, where the landslide originated, has been the scene of much wind farm development in recent years and local people have been quick to point the finger of blame at such development.
Community activists Joe Harrington and Kay O’Leary yesterday claimed wind farm development by investors with no local connections had “ravaged” a unique mountain area.
They said the Stacks and Glenaruderey mountains could be described as a bog slide waiting to happen.
“While wind turbines are presented as minor encroachments that stand benignly on our bog land, the opposite is the truth,” both claimed.
“Apart from the disastrous breaking of the hard mineral pan that supports the bog, the fabric of our blanket bog land is being rent asunder by the roads built to each turbine.
“Unlike the midlands, the bog here [north Kerry] is blanket. It lies on the hills holding water like a sponge and local experience and knowledge is ignored when dealing with it in favour of engineers who never walked a moorland never mind worked it.”
This has not been the only significant bog slide in the area, according to Mr Harrington. Records going back to 1880 show that the area had a particularly bad bog slide then, which was as devastating to the local environment as the latest event.
In July, the European Court of Justice ruled against Ireland in a case involving a wind farm project at Derrybrien where the landslide killed tens of thousands of fish.
The court said a proper environmental impact assessment should have been carried out before the project proceeded. The Derrybrien wind farm project was one of the largest in Europe.
The ruling will have big implications for the way the Government allows other projects to proceed before full environmental checks, required under EU law, have been carried out.
At Derrybrien, 450,000 cubic metres of peat were dislodged over a 32km area, polluting a river and killing 50,000 fish. The Government argued that this was caused by poor construction work, but the court found it was because a proper environmental impact assessment (EIA) had not been carried out.
In its latest report, the Geological Survey Office warns of a continuing and underestimated risk of serious landslides in potentially hazardous areas. It says surveys of these areas should be undertaken and the Government should introduce more stringent planning controls to curb the risk and the cost of future landslides.
The expert group says steps need to be taken to integrate landslide issues into the planning process. It further warns there will be increased landslide activity as development in Ireland increases in the years ahead.
Most recorded landslides did not result in loss of human life, but a tragic occurrence at Gneeveguilla, on the Cork/Kerry border, in the wet winter of 1896 resulted in eight deaths.
In what became known as the Moving Bog Disaster, quarry worker Con Donnelly, his wife, and six of their children were all swept away as they slept peacefully in their cottage.
