An application to build the Dublin Metrolink rail line is unlikely to be made until 2020 due to delays in determining a revised route for the line, it has emerged.

Transport authorities had been due to announce the redesigned route of the line last August, but postponed their decision, and had been expected to publish the route details by November.

However, publication of the revised route was further delayed until the new year to allow time to design an extension of the underground section past Ranelagh in south Dublin. The additional tunnelling was likely to add more than €100 million to the cost of the €3 billion line.

It is now understood the revised alignment will not be ready until February at the earliest and the application to An Bord Pleanála to build the line, due to be submitted in 2019, will not now be made until 2020.

Construction of the line was due to start in 2021 for completion in 2027 and it is not yet known if this schedule will be affected.

Upgrade

The preferred route of the metro line, which combines the previously planned Metro North from Swords to the city centre with an upgrade of the Luas Green line between Charlemont and Sandyford, was announced last March.

However, in the subsequent months the transport authorities came under pressure from senior politicians – including Taoiseach Leo Varadkar and Minister for Housing Eoghan Murphy – as well as the GAA to alter the route.

The route had involved the use of Na Fianna GAA club and adjoining school pitches on Mobhi Road in Glasnevin for a major construction site. Mr Varadkar last May said the proposals would cause “enormous damage” to the schools and sports clubs that use the Glasnevin lands.

It had also required the closure of a road linking Rathmines and Ranelagh in south Dublin. Mr Murphy asked the transport bodies to scrap plans to close the level crossing from Dunville Avenue to Beechwood Road in Ranelagh, which would force motorists into a 1.2km detour.

Two solutions

The transport authorities initially prepared two solutions for the Dunville Avenue crossing; one involved the construction of a rail bridge over the road, the other would see the construction of a railway “cutting” allowing the train to travel under the road. These options would have added in the region of €25-€35 million to the line’s €3 billion budget.

However, these options were not acceptable locally, and the authorities are planning to extend the tunnel, which was due to end at the current Luas Charlemont stop north of Ranelagh, south, past the Dunville Avenue junction.

Lands belonging to Home Farm Football Club are expected to be used instead of the GAA lands.

A spokesman for the National Transport Authority said there were a “number of very important public concerns and engineering elements contained within a project this scale and complexity” which it was working to resolve.