An estimated €300 million has been spent on the Dublin MetroLink system, despite no construction having begun.
Reports say every year of delay to the project adds between €100 million to €300 million to the final bill.
Brian Caulfield, Professor of Transportation at the School of Engineering at Trinity College Dublin, told The Hard Shoulder this total is actually small change.
"That €300 million would have gone into all of the reports, the consultants, the engineers reports that have been done to date," he said.
"It's kind of in line to what one would expect for a project of this scale that we're trying to achieve.
"I suppose when you look at the overall capital cost of the project, it's expected to be between €9 and €12 billion, so €300 million is almost like small change when it comes to the overall cost of the project.
"A lot of money would have been spent as well on answering objections to the project that have happened to date".
'Sticks out like a sore thumb'
Prof Caulfield said several factors have got us here.
"Dithering, politics; I think we should have done it back when we had planning permission for this line, Metro North, back in 2011," he said
"We're hoping to get to the stage at some point this year where we have planning permission for it again.
"It sticks out like a sore thumb across Europe in terms of cities that are connected by rail to the airport.
"Only about 25% of all of the trips will service the airport - the rest is north county Dublin, that have been waiting for this project for 33 years".
An artist's impression of a proposed MetroLink station entrance at St Stephen's Green in Dublin city. Picture by: MetroLinkProf Caulfield said the MetroLink needs an Ardnacrusha "level of ambition" around transportation.
"It's that level of thinking and that level of urgency that we need," he said
"When we started off planning and talking about a Metro, the same thing was happening in Copenhagen and they've now built a number of lines.
"There's examples in Madrid and Barcelona - lots of these other cities have managed to do it.
"If we had gone with even the original 2011 planning permission, I would argue that we would be starting to talk about the next line.
"But where we are at the moment is we're still at square one, almost, and hoping that we get planning permission again".
The route for the Dublin MetroLinkProf Caulfield said any further delay will only cost us more.
"The likelihood would be that we get might operation [in] 2034/35, and that's what the documents are saying," he said.
"If I was a betting man, I think at the moment a lot of things are aligned in favour of this.
"I think there's broad cross-party support on it... I think most parties are in favour of this project.
"The only thing that's going to happen if we delay it, it's going to even cost more," he added.
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