LONGER Luas trams are planned in order to deal with capacity problems on the system.
The National Transport Authority (NTA) pointed out "capacity constraints" are already in evidence.
"Further investment will be required to ensure that the Luas system retains the carrying capacity to deliver the number of passengers seeking to use the service," the NTA stated.
It is also intended to invest in measures to improve accessibility to stations.
The major light rail infrastructural project for 2013 to 2018 is already under way – the Luas Cross City. The scheme will involve constructing a Luas line extending from St Stephen's Green to connect to the Maynooth Rail line at Broombridge in Cabra.