Separately, because of Noah Smith’s opinions about high-speed rail, today there is going to be an event featuring me and him in which we are going to discuss the issue in an American context, alongside a presentation of the database and what lessons can be drawn from it. You can register here; it’s at 13:00 Eastern US Time, or 19:00 Berlin time.
A few notes regarding our database, because I’m being asked on Twitter, and also because it’s relevant for our research:
This is a well-studied topic
Literature on comparative HSR costs already exists, and some of our internal cost references are to studies on the subject. This is not like subway costs, where the biggest databases I know of prior to ours are a Flyvbjerg paper and a Spanish analysis each with a number of items in the teens. This should not in a way be surprising: the costs and impact of megaprojects are analyzed more than those of smaller projects, and subways are megaprojects of greater size than surface transit or street reconstruction but HSR is of yet greater size. Thus, subways are significant enough that we have been able to find largely complete costs from trade and mass media and government reports, which task is far harder for bus lanes or bike lanes, whereas with HSR, not only is it possible to find complete costs, but also there is extensive public debate and analysis.
I believe our contribution to the discussion, then, is not the database itself, but two new points:
- Contrary to the World Bank report on the subject (see here, starting printed page 39), China does not build HSR especially cheaply. Our findings are not too different from the World Bank’s for lines built up to the publication of the report measured in yuan per km, but we adjust for PPP and therefore the cost in dollars per km is higher, and, moreover, the more recent lines appear to be more expensive. In fact, Chinese costs are higher than European ones. The reason is that China builds its HSR almost entirely on viaduct, whereas in Europe, viaducts are rare, and segments that are not in tunnel are built at-grade or on earthworks.
- There is positive correlation between a country’s HSR costs per km, net of tunnels, and its subway construction costs. This is not perfect correlation, but one can see Britain, the Netherlands, and Taiwan perform poorly in both areas. France and Germany are in the middle. Spain is very cheap. The exceptions are notable: Italy has cheap subways and expensive HSR, which Paolo Beria, author of one of our source papers, attributes to overbuilding and overdesign, with extensive tunnels and freight-friendly grades.
We only include under-construction or open lines
This contrasts with lines that are only in early design and may not yet have a cost – for example, Frankfurt-Mannheim will only publish its cost estimate next year, in a parliamentary budget setting in order to decide whether to proceed (for which the answer is certainly yes, as the benefits to the network are intensive). This also contrasts with canceled and indefinitely postponed lines, such as California High-Speed Rail and the Portuguese lines killed during the Great Recession’s austerity. Canceled lines are upward-biased: the state is likelier to cancel or choose not to build a line if it is more expensive than the average, as we can readily see with California, and therefore we do not wish to compare built with unbuilt lines.
The above analysis is equally true of our subway construction costs database – if a line is canceled, it is purged, even if design or even physical construction began. Gateway for example is under active design and engineering and is therefore included, even if they are still seeking funding, but if it is canceled it will be purged (but if it is rebooted, as I hope, then the sunk cost will be included, as with the Green Line Extension in Boston).
The difference is that our HSR cost database is more historic. It is close to complete for France, Germany, Italy, Spain, Belgium, and Korea, and complete for single-line Taiwan and the Netherlands and for the UK. This is because it’s just easier to find historic data for HSR than for subways, where I wish I could get a complete historic series for big cities with big systems like Paris, Madrid, and Berlin, but can’t even find 1970s-80s costs for any of them. Conversely, ongoing projects make it surprisingly difficult at times to find tunnel and viaduct percentages, and the escape path of going on Google Earth and OpenStreetMaps and measuring is not available.
What is included?
As far as possible, costs are for civil infrastructure, systems, stations, and overheads, but not rolling stock or financing charges. Austria’s Koralmbahn has two sets of numbers, differing by a factor of 2, with one source claiming that it is about whether financing is included. It is my belief that, owing to the high profitability of HSR if cost of capital is ignored, it is best to think in terms of returns on investment and not try to incorporate debt or finance charges into the actual cost.
The importance of avoiding viaducts and tunnels
The Asian tendency to build on viaduct where the line is not in tunnel leads to high costs. Likewise, the use of shallow grades and low superelevation for mixed lines or even for some dedicated lines (the Shinkansen, without any track sharing, hews to 1.5% grads) raises construction costs.
Netting out tunnels is still useful when trying to figure out itemized costs and cost control that is not about what to build, for example about labor or procurement. It is also useful when comparing lines in the mountainous terrain of Austria, Japan, Korea, and Switzerland to the easier North European Plain. But at some point, it is necessary to treat the tunnel percentage as endogenous to the planning system. The viaduct percentage, moreover, is absolutely endogenous.
France in this context does well by keeping lines at grade as much as possible. The only country with less tunneling than France is Morocco, which builds its urban and high-speed trains as if it were France, and, thanks to France’s extensive presence in the Maghreb, French contractors are intimately familiar with the local situation and build cheaply. France and Germany have similar unit costs, but Germany tunnels a lot more, less because of the terrain and more because of either politics (that is, the Erfurt detour for Berlin-Munich, forcing the line to go through thicker mountains) or a misguided attempt at building mixed lines in the 1980s and 90s.
The United States’ high projected budgets for proposed lines that never go anywhere thanks to their extreme costs come from overbuilding more than high unit prices. For example, in Baltimore, a two-track tunnel project designed for exclusive electric passenger train usage turned into a four-track tunnel with enough room for double-stacked freight with mechanical ventilation for diesel locomotives. The scope creep raised the projected budget from $750 million in the late 2000s to $4 billion in the mid-2010s.