More than €19m in additional development levies that has been stumped up by builders and property owners along the route of the Metro North project will have to be returned if the project is axed, the Herald can reveal.
Two Dublin councils have been collecting the money on behalf of the Rail Procurement Agency since 2007 in the form of an increased development levy.
The levy has made the costs of construction along the route from St Stephen's Green to Swords more expensive over the last eight years.
Fingal County Council has collected €14m in that time, while Dublin City Council has collected €5.4m - with the cash ring-fenced pending the approval of the long-planned transport project.
However, that will all have to be paid back if Metro North is not selected by the government from the six northside public transport schemes currently being considered.
Other options include heavy rail and a rapid bus corridor.
Transport Minister Paschal Donohoe is to announce a decision within weeks when he reveals his capital budget.
Metro North was first proposed in 2005, with a completion date of 2012 promised by the Government of the day.
An increased development levy along the route was introduced to contribute to the projected costs of more than €2.55bn as a condition of planning permission that was granted.
The levy applies to buildings and properties in a 1km radius of the route, as that area is deemed within walking distance of the metro stations.
The plan was stalled in 2012 due to the recession, but the councils continued to collect the money amid an expectation that the Metro North plan would be back on the table when the economy improved.
The additional charge varies between council areas. DCC charge €322,000 per hectre for retail space, while Fingal charge €945,000.
For commercial space, DCC charges €223,500 per hectre compared to Fingal's €693,000.
It costs some €2,500 for a single residential unit in the DCC area, while in the north Dublin area the charge is by the hectre at a cost of €304,500.
A revised Metro North plan costing €2.1bn is being considered by the government but, if it is scrapped, the levies will have to be returned.
Fianna Fail's Mary Fitzpatrick said she has called for the levies to be suspended on a number occasions.
"It's not helpful for the city's economy for the Government to be taking that money from property owners," she told the Herald. "That money could have been put to productive use, but instead it has been sitting in a holding account for a project that has been shelved."