Disruptions to train services on the Dublin to Portlaoise line will begin this Saturday and continue on selected weekends for most of the year.
Iarnród Éireann said it is to resume works on line improvements on the Dublin to Portlaoise line, focusing on the section between Hazelhatch and Portlaoise.
The works will affect services to Westport, Galway, Limerick, Cork and Waterford.
The selected days include the first three Saturdays in April, two Saturdays in May and a range of Saturdays throughout June, July, August, September, October and November.
The works will also see alterations to services on Bank Holiday Sundays in May and October.
Iarnród Éireann said train services will operate in full on affected dates, but to a revised timetable with the exception of bus transfers between Heuston and Athy for Dublin - Waterford passengers.
The improvement works, which are being undertaken at a cost of €9 million are, aimed at improving speeds for trains on the line and follow a similar investment of of €10 million last year.
The works involve improving the track substructure, by the removal and replacement of degraded crushed stone ballast which supports the railway track structure. In addition track drainage and track geometry will be improved.
The rail company said the investment will lead to “ higher reliability, smoother running of trains and with other works deliver consistent 160km/h speeds (100 mph) by the end of 2016 on this section”. This will deliver journey time improvements for customers.
On affected Saturdays, a trolley service will be provided on all Intercity services to / from Heuston. First class facilities will not be available. Dining car and restaurant car facilities will also not be available.