Northbound DART services are operating as normal this morning after the line between Connolly and Kilbarrack stations was closed yesterday for repairs.
However, the company reminded commuters that a "Saturday service" was in operation today. The damage was caused by the collapse of casing on a gas pipe on a bridge over the railway line on to overhead wires.
Commuters on the Drogheda and Belfast Enterprise services and northbound DART users suffered severe delays yesterday.
An Iarnród Éireann spokesman said the damage was not as bad as had been feared initially.