Dublin traders and Opposition parties have accused Iarnród Éireann of "treating commuters with contempt" by closing the southside part of the DART for a 10-day period after Christmas.
The Dublin Chamber of Commerce, the Small Firms' Association and individual city centre businesses were among those to condemn the move, claiming it will significantly damage trade over the New Year sales period.
But the company's stance was backed by the Minister for Transport, Mr Brennan, who said it was "the best time to do the work" given the alternatives.
A spokeswoman for Irish Rail said the works, which were part of a project aimed at increasing the capacity of the DART by at least 30 per cent, could not be completed without causing some inconvenience. The post-Christmas period had been chosen specifically "to minimise the impact for commuters, and deliver best value for money". Services are to be suspended between Connolly Station and Greystones between St Stephen's Day - on which trains don't normally operate - and January 4th inclusive. Currently, works on the line are only taking place at weekends to minimise disruption.
Mr Brennan said he "supported" the company's approach in light of its decision to keep services running over the pre-Christmas period. "I made it clear when I asked CIÉ to leave the DART running up to Christmas. . . that that meant making up for that time in the valley period after Christmas, and the valley period after Christmas is approximately from Stephen's Day to the fourth of January.
"We have to manage. It is €170 million of work. It will greatly increase the number of people who will use DART, and the work has to be done. It is the best time to do the work. So I support the company on that."
The Small Firms' Association said its phone lines were jammed yesterday "with irate business owners who are angry, dismayed and perplexed about this decision". The group's director, Mr Pat Delaney, said city centre businesses were already reporting a 14 per cent drop in trade because of the weekend DART closures. The post-Christmas closure "will have a devastating effect on companies who are already suffering because of the Luas disruption and a significant reduction in consumer spending".
Mr Eddie Shanahan, group marketing manager of Arnotts, said the timing could not be worse given the first shopping day after Christmas was "the biggest day of the retail year". Taken in the context of "an assault on car drivers in Dublin city" and an "ill-conceived public transport service", he said "there appears to be a concerted effort between several State agencies to destroy the city centre of Dublin."
The Labour Party transport spokeswoman, Ms Róisín Shortall, accused Irish Rail of treating the public with "utter contempt".
"Over the past few weeks we have had a series of confused and contradictory statements about the closure of the southside DART line from the Minister for Transport Séamus Brennan, from Iarnród Éireann, and from the chair of the transport committee, Fianna Fáil deputy Eoin Ryan."
