A very close call for lucky Wexford
Published 11/02/2014 | 05:38
WEXFORD town dodged the bullet when the storms struck last week, with Borough Engineer Sinead Casey saying the Main Drainage Scheme had been a major factor in preventing flooding.
But it was a close call, with just a foot to spare on the quay wall and waves breaking on to the quay itself.
While low-lying businesses laid sandbags at their doorways, the town escaped the kind of flooding that it suffered from in the past when spring tides were high and south easterly gales were blowing.
Not that it may never happen again, but unless there is a particular set of circumstances the odds are stacked against it.
The pipes, including surface water pipes, combined sewers and gullies draining the town, are connected to the main interceptor sewer.
Sinead said that prior to the commissioning of the drainage system all these outlets drained through the old Quay wall into the harbour and during a very high tide event the old culverts flooded and made it nearly impossible for surface water get away quickly.
This was evident on the Crescent on Tuesday night. The structure at the Crescent contained the flood waters on the night.
'The gullies around the Crescent are connected to the Interceptor sewer and therefore are independent of the tide so the surface water was carried away but the flood water did not come back up the pipes and flood the road,' she said.
Raising the structure of the Quay in general also has contributed to the protection and the increased free-board on the quay wall offers protection during surges.
'Saying that, we were only inches away from the Crescent over topping. We had approximately a foot to spare on the Quay wall, but waves were overtopping and breaking on to the Quay.'
Other flood protection works that made a contribution include the Wexford RNLI development near the bridge. The structure has built-in flood protection walls and the security wall and railings on site also act as flood walls. This site flooded historically in previous similar conditions and did cause the Wellington Place and Selskar end of town to flood also.
The repairs to the sea wall behind the storage sheds at the north station also gave excellent protection last Monday and Tuesday.
The critical factor then and also during previous storms in recent weeks is the wind direction. The factors that are constantly monitored in Wexford are height of tide, tidal surges, atmospheric pressure, level of rainfall, wind speed and direction. A certain combination of all these factors could lead to flooding on the Quay and Crescent.
The infrastructure in place can now cope reasonable well with the first five factors, but if the wind direction is not favourable, that is if the wind is blowing consistently from the east or south east for a prolonged period with a high tide, tidal surge, very low atmospheric pressure and gale to storm force winds, Wexford is in trouble.
Sinead said: 'All the indications on Monday and Tuesday morning had been for flooding on the Quays. The Borough Council spent Tuesday preparing for the worst. Approximately 1,500 sandbags were prepared and delivered.'
There was very minor flooding at the Cinema Lane car park, but it was miniscule compared to what happened in New Ross.
Sinead said assistance from the Gardaí, Civil Defence volunteers, RNLI volunteers and Marinewatch volunteers was given on the night.
New Ross Standard