Ireland's loss of native woodland is almost complete, with less than 1 per cent of the land area wooded, the lowest in Europe other than Iceland, according to an extract from an Office of Public Works report read to the High Court yesterday.
Ireland's native woodland is vulnerable to total annihilation, the 1991 report added. It described the Glen of the Downs as "a very rare habitat" which merited strict conservation.
The proposed £18.5 million dual carriageway through the glen would irrevocably destroy the woodland aspect of the glen, an arboricultural consultant, Dr Dealga O'Callaghan, warned.
He said the destruction would occur through a combination of tree-felling and alteration in soil water and drainage patterns, the latter of which would have a pervasive effect on the trees to be retained, including disruption of rooting patterns and exposure of trees to wind throw.
All of this would cause a rapid decline in tree and woodland health, Dr O'Callaghan said.
"This significant site of national and international scientific interest will be altered for ever."
The report was read on the third day of a challenge by Mr Dermot Murphy, a computer technician, formerly of Exchequer Street, Dublin, but now living in Galway, to Wicklow County Council's planned road scheme at the Glen of the Downs, Co Wicklow.
Mr Peter Bland, for Mr Murphy, read to the court an affidavit by Mr David Ball, a consulting hydrogeologist. He said an Environmental Impact Statement produced in 1991 regarding the proposed road scheme in the Glen of the Downs did not include any analysis or any specific reference to ground water.
This omission had led to significant flaws in the understanding of the relationship between water in general and ground water in particular, and the overall ecology of the glen, Mr Ball said.
The 1991 EIS had stated that the stream at the glen was especially important for maintaining the healthy state of the springs in the ash-hazel woodland there. But, Mr Ball said, it was "well known that water does not flow uphill."
The springs in the ash-hazel woodland were above the stream and therefore the stream could not maintain the springs.
If a proper assessment had been carried out, and the fact noted that the ground-water flows which feed the stream would be intercepted by the drains to be constructed along the road margins, then it would become clear that this source of water supply, which was vital to feed the stream and to the whole ecology of the woodland, would be significantly altered.
This part of the glen was home to a very rare invertebrate species, the fly Mycetobia obscura. The oak trees in the glen were also likely to be susceptible to changes in ground water.
In another affidavit Mr Brendan O'Donnell, executive engineer with Wicklow County Council, said no public rights of way in the glen had been extinguished in the manner claimed by Mr Murphy.
He disagreed with claims that the road scheme would affect more than some 500 trees, or that a forestry consultant who inspected trees for the council had not done so thoroughly.
The hearing before Mr Justice Kearns resumes on Tuesday.
