When a major disaster strikes and roads go down, restoring expressways matters more to economic recovery than rebuilding high-speed rail, according to a new study. The finding challenges assumptions about which type of transportation infrastructure deserves priority attention in disaster response.
The research, published in Transportation Research Part A: Policy and Practice and reported by Phys.org, is described as the first to scientifically demonstrate the role that transportation network restoration plays in rebuilding regional economies after a major disaster.
The team was led by Professor Sunbin Yoo of the Department of Energy Science at Sungkyunkwan University, working in collaboration with Fukuoka University, Beijing Normal University, Korea University, The Hong Kong Polytechnic University, and Beijing Normal University-Hong Kong Baptist University United International College. The researchers used big data from 2006 to 2020 covering more than 1,700 municipalities across Japan.
The study focused on how restoring what the researchers call market access, meaning the size of the population and market reachable within a given travel time, affected real economic outcomes. They compared the effects of restoring the Shinkansen high-speed rail network with those of restoring the expressway system following major disasters, specifically examining the aftermath of the 2011 Great East Japan Earthquake.
The results were clear. Expressway restoration had a much broader and stronger positive effect on manufacturing recovery, population movement back into affected areas, and new business formation than high-speed rail restoration did.
The reason comes down to connectivity. High-speed rail primarily serves business travel and service industries around major hub cities like Sendai. Expressways, by contrast, provide door-to-door connectivity that reaches deep into local communities. They are used to transport manufactured goods, haul building materials, and allow workers to commute. When expressways come back online, the local manufacturing ecosystem can begin functioning again relatively quickly.
The study used counterfactual simulation to estimate what would have happened without expressway restoration. The results showed that additional economic losses of approximately 567.3 billion yen per year, equivalent to over 5 trillion Korean won, would have accumulated as of 2020 if expressways had not been restored.
Yoo said the findings have implications beyond Japan. "This study holds significant value in scientifically proving that after a major disaster, rapid reconstruction of the expressway network, which connects local production sites and logistics, is just as essential as restoring hub-centered high-speed rail to revive local communities," he said. He added that the research "will serve as an important guideline for enhancing economic resilience in future disaster response policies and national infrastructure planning."
The study draws on one of the most extensively documented disaster-and-recovery datasets available, making its findings applicable to how governments around the world prioritize infrastructure rebuilding after earthquakes, floods, and other large-scale events.
