In the recent series of natural disasters that hit Japan, the damage to infrastructure, resulting in large-scale blackouts in quake-hit Hokkaido and paralysis of Kansai International Airport’s functions when the area was devastated by Typhoon Jebi, exacerbated the impact of the calamities. National and local governments across the country need to inspect the resilience of infrastructure against big disasters and take measures to repair and strengthen that which is found to be vulnerable to damage. Such a task is all the more urgent given the greater frequency of extreme weather, which is linked to climate change, and the fact that big disasters can hit anytime and anywhere in this country — as recent events have reminded us.
After southern Hokkaido was hit in the early hours of Sept. 6 by the magnitude 6.7 earthquake, which registered the maximum 7 on the Japanese seismic scale, the supply of electricity in the island prefecture was temporarily cut, affecting nearly 3 million households and disrupting medical service at hospitals, along with operations of airports and railways. The shutdown of the Tomato-Atsuma power plant near the quake’s epicenter, Hokkaido Electric Power Co.’s largest thermal power plant — accounting for roughly half its power generation — triggered a halt in operations at other power plants.
While the power outage has since been mostly resolved, concerns remain over power shortages — particularly as the winter season approaches in the northernmost prefecture — since the Tomato-Atsuma plant won’t return to full operation until at least November. The government has ordered power companies across the country to examine their preparedness for big disasters to assess the risk of similar large-scale blackouts. Whether a system is in place to contain the effects of possible damage to power-generation facilities in the event of major disasters should be scrutinized. The viability of the system for supplying emergency power from other regions in the event disasters lead to power outages — which broke down in the case of the Hokkaido quake — needs to be verified.
The havoc wreaked on the Kansai region by Typhoon Jebi earlier this month exposed the vulnerabilities of Kansai International Airport, a key gateway to the region that was built in 1994 on artificial islands in Osaka Bay. The airport was temporarily shut down after the powerful typhoon caused high storm tides that flooded it. The connecting bridge to the airport was badly damaged when heavy winds and waves blew a tanker into it. Thousands of people, including passengers, were stranded overnight in the airport, which partially lost power after transformers located in the basement floors were flooded.
The risk posed by high storm tides and tsunami have in fact been a problem for the airport since its opening. Completed in 1994, the airport’s first island has since sunk by 3.5 meters and its runway is only 2 to 3 meters above sea level. Three of the six power transformers located in the basement of the Terminal 1 building broke down when they were flooded. Given that the exposure to the danger of high storm tides has been known from the beginning, it should be thoroughly examined whether sufficient measures have been taken, such as building higher seawalls, better protecting its underground facilities from flooding and moving vital electrical equipment to higher floors.
Several other airports in Japan, including Chubu Centrair International Airport in Aichi Prefecture and Tokyo’s Haneda airport, are built on artificial islands or coastal landfills — locations that reduce the problem of jet noise over big cities near the airports. Whether these airports can withstand high storm tides like those caused by Typhoon Jebi, or tsunami in the event of a mega-quake in the Nankai Trough off the Pacific coast, should be scrutinized.
Climate change amplifies the risks posed by extreme weather conditions and typhoons are becoming more powerful and causing greater damage. The government and operators of key infrastructure must brace for worst-case scenarios that defy the experiences of past disasters. It is impossible to foresee the magnitude of big disasters or when they will hit, but we can take steps to make crucial infrastructure more robust so that the impact can be limited and infrastructure that is damaged can be quickly restored.
Even as the damage to infrastructure caused by the recent series of disasters is gradually repaired and the situation returns to normal, how they were damaged should be closely examined so similar problems can be averted when disasters strike in the future.