BEIJING —  By the end of 2013, China had built a high-speed rail network of over 10,000 route-km (6,000 miles), far exceeding that in any other country and larger than the network in the entire European Union. It has been accomplished at a cost which is at most two-thirds of that in other countries, according to a new report.

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A new World Bank paper takes a look at this expansion, its construction unit costs and some of its key cost components. It also outlines reasons that may explain the comparatively low cost of high-speed railway construction in China.

According to the paper, "High-Speed Railways in China: A Look at Construction Costs," several factors influence the cost of a high-speed rail project construction. The major factors include the line design speed, topography along the alignment, weather conditions, land acquisition costs, use of viaducts instead of embankments, the construction of major bridges across wide rivers, and the construction of mega stations.

Laying track on viaducts is often preferred in China to minimize resettlement and the use of fertile land as well as to reduce environmental impacts. The estimated cost of viaducts in China ranges from RMB 57 to 73 m/km ($9 to $12 million U.S.) for a double-track line. Such costs are kept low through standardization of the design and manufacturing process for casting and laying bridge beams on viaducts.

Special bridges that cross large navigable rivers or that need to accommodate special topographic features like mountains have much higher cost per kilometer than that of a regular viaduct. Usually such bridges represent a small percentage of the total number of bridges. Projects having larger proportion of special bridges tend to have a high unit cost.

Railway stations play a dual role as transport hubs and urban centers. Small stations (3,000 sq m station building) cost about RMB 40 million ($6.5 million) and account for 1.0 to 1.5% of the total project cost, while mega stations may cost up to RMB 13 billion ($2 billion) and are frequently built as independent projects.

The paper notes that construction cost of high-speed rail in China tends to be lower than in other countries. China’s high-speed rail with a maximum speed of 350 km/h has a typical infrastructure unit cost of about US$ 17 to 21 million per km, with a high ratio of viaducts and tunnels, as compared with US$25-39 million per km in Europe and as high as US$ 56 million per km currently estimated in California.

“China has accomplished a remarkable feat in building over 10,000 km of high-speed railway network in a period of six to seven years at a unit cost that is lower than the cost of similar projects in other countries,” said Gerald Ollivier, a World Bank Senior Transport Specialist and co-author of the paper. “Besides the lower cost of labor in China, one possible reason for this is the large scale of the high speed railway network planned in China. This has allowed the standardization of the design of various construction elements, the development of innovative and competitive capacity for manufacture of equipment and construction and the amortization of the capital cost of construction equipment over a number of projects.”

This paper is the ninth of a series of papers on transport topics produced by the World Bank in Beijing. The World Bank has supported six railway projects with speeds ranging from 200 km/h to 350 km/h in China.