'Over budget, over time, over and over again' - the curse of thinking too big
As Dublin looks to expand its tram system, the plan risks running into the Iron Law of Megaprojects, warns Colm McCarthy
Last Thursday saw the release by the National Transport Authority (NTA) of the preferred routing for the next addition to the Dublin tram system, formerly called Metro North and re-christened MetroLink. This will be an expansion of capacity on the existing Green line from Sandyford in the south of the city and a new line, much of it underground, through the city centre and on northwards to the airport and Swords. The trams will be bigger than those originally ordered for the Red and Green lines but will operate on the same gauge of track, narrower than mainline or suburban rail.
They will squeeze in 500 passengers, mainly standing, when fully loaded, versus around 300 for the shorter first-generation Luas trams. Suburban trains are bigger and can take 1,000 passengers or even more. Total cost for MetroLink is estimated at €3,000m, which would make it easily the most expensive single project ever undertaken in Ireland.
In addition to the routing, on which there will be a public consultation, the NTA released a 28-page summary cost-benefit study prepared by the engineering consultants Systra, a French company whose principal shareholders are RATP, which operates the metro and the regional railways around Paris, and SNCF, the French national rail company. A full cost-benefit study is promised once the consultation phase has been completed. The ratio of capital cost (three thousand million euro) to the length of the cost-benefit study as published works out at more than €100m per page and it is surprising that the board members at the NTA felt able to sign off on this huge project on the basis of such a succinct evaluation.