A growing cadre of researchers, advocates, and experts are asking: why does it cost so much to build infrastructure, particularly public transit, in the United States? Last year, Eno kicked off a major research initiative analyzing cost and timeline drivers affecting the delivery of rail transit in the United States. A crucial aim of this research is to understand if and how costs are high, particularly when compared to other countries.

To learn more about Eno’s transit project delivery research, click here.

To investigate the relative success and challenge of building transit, the Eno team created a database of projects. The database includes construction cost and timeline data for a total of 171 domestic and international rail transit projects completed over the past 20 years. For each project, factors such as number of stations, grade alignment, station spacing, and mode allow for deeper comparisons.

The full database and analysis can be found here.

The purpose of this database is to help draw conclusions about the extent to which transit construction costs differ in the United States and peer countries, as well as shed light on the differences between project characteristics and complexity across countries. The initial insights from this data help form the questions and themes we investigate in further detail through regional case studies. The database will be continually updated with more information and insights as they become available.

Robert Puentes, Eno’s President and CEO, said “If the United States is going to build more and better mass transit, projects have to be delivered in a timely and cost-effective way. This database is an essential tool to help us understand and compare transit projects both domestically and abroad.”

An initial look at the data supports five takeaways, all of which are explained in detail on the main database page. Those are, in a nutshell:

1. Light rail is not necessarily cheaper than heavy rail. Grade alignment, rather than mode, is the major determinant of cost. Defining the mode of a transit project – whether it’s light rail or heavy rail – does not correlate well with its construction cost. Most of the construction and planning inputs for both modes are the same. A transit line, whether heavy or light, includes laying track, installing electrical systems, and building accessible stations. The main difference between the two modes is that light rail tends to be mostly at-grade, and heavy rail is often either tunneled or elevated. However, heavy rail projects outside of the U.S. appear to be largely below grade compared to U.S. projects.
2. Many rail projects in the United States are relatively inexpensive. When excluding the two New York City megaproject outliers, costs per kilometer in the United States average $107 million ($162 million including New York), while non-U.S. projects in the database average $138 million per kilometer. Of the 67 U.S. projects in the database, 43 cost less than $100 million per kilometer, although most of them are built at-grade. These costs are mostly in line with construction costs for similar European and Canadian tram and light rail lines that also run at-grade.
3. The United States pays a premium for tunneled projects. U.S. projects that are primarily at or above-ground (less than 20 percent of alignment below-ground) cost an average of $73 million per kilometer, which is slightly higher but overall comparable to the average cost of $52 million per kilometer for similar projects abroad. However, projects that are more than 80 percent below ground are built at an average cost of $354 million per kilometer in the United States ($756 million per kilometer including New York City), a 65 percent increase over similar projects abroad ($215 million per kilometer, on average).
4. Cost variability increases significantly for tunneled projects. Outside of the United States, where tunneled projects are more common, below-grade lines range from as low as $80-120 million per kilometer for fully underground tram and metro lines in Spain and France, to as high as $300-550 million for subway projects in Barcelona and London (and some Parisian Metro lines). However, tunneled projects in the United States range from $250-580 million per kilometer (and up to $2 billion for projects in New York City). There are significantly fewer U.S. tunneled lines in the database compared to international projects, and the presence of two large outlier projects in New York City further contributes to the dramatic variation in U.S. costs for tunneled projects.
5. Stations are expensive, but international projects include more of them. For tunneled projects in the United States, the database shows stations accounting for around 25 percent of total project costs. Research shows that station depth and architecture is a potential project cost driver. But despite their generally lower cost per kilometer, international projects have closer station spacing on average, which is usually more common and useful in dense downtown areas. However, the database analysis shows station spacing does not seem to have a clear correlation with cost.