The 18km-long proposed light-rail system in Dublin, Ireland, will cost €2.5bn ($3.47bn), rather than the original estimate of €3.7bn ($5.13bn).

The Metro North project will connect Swords to Dublin city centre and will serve destinations including Mater Hospital , DCU, Ballymun and Dublin Airport.

To date, the Railway Procurement Agency has spent €175m ($242.9m) on land acquisition, pre-construction works and planning.

The metro system, which is awaiting final approval from the Irish planning board, could cost about €138m ($191.59m) per kilometre, according to independent.ie.

The project is expected to generate over €1bn ($1.3bn), while a final cost-benefit case has to be worked once the board decision is made.

The European Investment Bank has approved €500m ($694m) funding for the project, and subject to the necessary approvals being granted, work will start by the year’s end or early 2011.