Metro-style Green Line upgrade to add capacity
Transport bosses are considering upgrading the Luas Green Line to become a high-capacity Metro system to cater for future population growth.
The National Transport Authority (NTA) is looking at extending the proposed Metro North system, planned to run between Swords and St Stephen's Green via Dublin Airport, to take in the Luas Green Line to Sandyford.
The €2.4bn Metro North scheme was shelved in 2011. It was designed to carry some 10,000 passengers an hour, with 10km of the 17km route in tunnels.
The NTA is examining if some of the line can be built above ground, to reduce costs.
It is also considering scrapping a number of stops around O'Connell Street, and redesigning the system to take in the existing Luas Green Line.
The work is being carried out in advance of a review of the Government's capital spending programme.
Reports suggest that Metro North could be brought forward by up to two years as part of the revised capital plan, meaning it would be delivered in 2024 or 2025.
The upgrade would mean that passengers could travel from Swords to St Stephen's Green on Metro North. But instead of the line terminating at St Stephen's Green, it would come above ground between St Stephen's Green and Ranelagh before continuing on to Sandyford on the Green Line route.
Passengers planning to use Luas Cross City, which opens before the end of the year, would change from Metro North at Ranelagh or St Stephen's Green.
"The environment has changed," NTA chief executive Anne Graham said. "There's new development plans on the route.
"We're looking to see how Metro North would tie in with the Green Line. We think we need that level of capacity with (long-term) housing plans for Cherrywood, Sandyford and Fassaroe (in Wicklow)."
Work is also under way on a redesign of the Dart Underground project, costed at €4.5bn but postponed in 2015.
The current plans include an 8.6km tunnel from Inchicore to East Wall with stations at Inchicore, Heuston Station, Christchurch, St Stephen's Green, Pearse Street and Spencer Dock.
The NTA is considering if tunnelling should begin at Heuston, instead of Inchicore, and terminate at Pearse Street. This would save "hundreds of millions", Ms Graham said.
In addition, the number of stations could be reduced. Those under threat include Inchicore, Christchurch and St Stephen's Green.
Modelling is under way to determine if the system could run to Pearse Street station and still provide the required connectivity.