Experts warn that despite increased disaster preparedness in the wake of the 2011 earthquake, Tokyo is vulnerable to calamity

Carlos Barria / REUTERS A man stands in front of a burned school after the March 11 earthquake and tsunami in Ishinomaki, in northern Japan, on April 7, 2011

When the Big One hits Tokyo, experts warn, the impact will be catastrophic.

In January 2012, the respected Earthquake Research Institute, at the University of Tokyo, reported there’s a 70% chance a 7.0-magnitude or higher quake will strike Japan’s capital by 2016. Such an event, the scientists said, could mean a death toll of up to 11,000 people and $1 trillion in damages on the world’s third-largest economy.

Predicting earthquakes can be dicey. It is much less reliable than forecasting other natural disasters, like hurricanes, and scientists increasingly fear reprisal for faulty guesses. Seven prominent Italian scientists were convicted of manslaughter last October for failing to accurately forecast a 2009 earthquake that left 309 dead and 1,500 injured in L’Aquila.

But that hasn’t stopped the earthquake conversation in Tokyo. Two years after a 9.0-magnitude quake and resulting tsunami devastated northeastern Japan, the country’s disaster-response experts are more nervous than ever about the ground beneath their feet.

(MORE: As Japan Marks One Year After the Tsunami, China Wonders Why Rebuilding Is So Slow)

Famed Japanese seismologist Katsuhiko Ishibashi has been sounding the alarm for years. His research, first presented in 1976, found that large earthquakes occur just southwest of Tokyo along the Pacific coast at intervals of about 100 to 150 years. Called the Tokai earthquakes, these tremors are the result of mounting pressure from two converging tectonic plates grinding past each other.

Underneath Tokyo, Ishibashi says, there are three converging plates. “There hasn’t been a large-scale earthquake around Tokyo since 1923,” he says. “There’s a high probability a violent tremor will strike the region [in the foreseeable future], stronger than the one that hit two years ago. It could be catastrophic.”

Tokyo’s government issued its own warning in August 2012 when it outlined a worst-case disaster scenario: a 9.1-magnitude quake unleashing a 34-m (112 ft.) tsunami along the Pacific coastline south of Tokyo, causing an estimated 323,000 deaths. Officials said the report was designed to encourage better disaster planning.

There is probably no country better prepared than Japan, where 20% of the world’s earthquakes occur. In Tokyo schools, for example, the government has installed nearly 300 seismographs transmitting data to a central authority over the past five years at a cost of more than $10.4 million.

Since the 2011 disaster, safety measures have only increased. The Shinkansen, or the “bullet train,” now features a faster braking system. Tokyo’s business district of Marunouchi is planning a disaster-management facility that will house medical facilities and emergency accommodations.

(MORE: Meltdown: Despite the Fear, the Health Risks from the Fukushima Accident Are Minimal)

The biggest developer in the district, Mitsubishi Estate, is confident its buildings can withstand a major quake. New high-rise designs meet or exceed the country’s strict code requirements, and older buildings are undergoing intensive retrofitting. Emergency generators are installed in buildings’ basements with flood-prevention measures including temporary metal walls and automatic doorplates. “We’re far enough away from Tokyo Bay,” says deputy general manager Toshiyuki Inoue. “The water is shallow, so there’s little chance of it reaching this area.”

Tokyo’s government is optimistic that flooding will not be a major problem. “Our estimated height for the biggest tsunami reaching Tokyo Bay would be no more than 2.61 m [8.6 ft.],” says Chikara Hoke, manager of the metropolitan disaster-relief division. “Seawalls in the bay are 3.5 m [11.5 ft.] high, which assure protection.”

But even a well-prepared city can be taken by surprise. Metropolitan authorities and contractors failed to close six of the city’s 44 floodgates and 46 seawall gates in Tokyo Bay after a tsunami warning on March 11, 2011. Authorities blamed telephone problems and traffic jams for those failures. Officials also said they had only considered flooding from typhoons and not tsunamis, prompting a major review of emergency facilities. Japan’s meteorological agency recently reworded its tsunami-warning system to make it easier to understand.

At risk are old downtown neighborhoods built on marshland that is below sea level. Tsunami flooding could also reach other sections of the city via its system of rivers and canals. Tokyo’s vast network of deep subways lines could also flood, trapping some of the millions of people who use the service daily. Tokyo Metro, one of two rapid-transit systems serving the city, will not reveal its emergency-floodgate locations citing security reasons. “We are hoping to coordinate with them,” says Hitoshi Kubo, of Mitsubishi Estate.

Tsunami flooding is not the only problem; there’s also a risk of fire. Storage tanks along Tokyo Bay holding petrochemicals and other flammable materials could crack and spill during a major quake, said Kimiro Meguro, a specialist in disaster-response strategies at the University of Tokyo. The spill could catch fire, reaching neighborhoods nearby. “It could also prevent fuel deliveries to thermal electric plants located near the bay,” he told reporters in 2012. “There may be a very serious power shortage for a long time.”

Tokyo Electric Power Co. (TEPCO) managed the city’s scheduled rolling blackouts after the March 11, 2011, disaster, but how exactly it would handle a massive power shortage or outage remains a mystery. “We do not know what kind of redundancy has been built into [TEPCO’s electricity transmission] network. It’s considered secret and not released to the public,” safety-management specialist Yoshiaki Kawata said in 2012.

Other potential complications from a major earthquake near Tokyo include volcanic activity from nearby Mount Fuji, which experts say reactivated after the 2011 quake, and a nuclear plant 200 km southwest of the city in the heart of the seismically volatile Tokai earthquake region. Authorities deemed the Hamaoka nuclear facility unsafe after the Fukushima accident, but economic pressure is spurring debate in the Abe administration about restarting the country’s 50 operable reactors.

Preparing the city for disaster requires short-term and long-term plans, says Ishibashi. “We have to break the old habit of what we traditionally call okami makase [relying on the ruler or government]. Individuals as well as companies must make preparations on their own. Self-action is of prime importance.” Long term, he says, “the national government needs to decentralize the megacapital and create a scattered homeland where centers for politics, business, culture and others are separated. Now everything is dangerously concentrated in Tokyo.”

Ishibashi admits this an enormous task. “It’s very difficult for most people to move out of Tokyo. It’s hard to find a new home or job in Japan’s current economic and social circumstances,” he says. “Also, the Japanese have a mind-set of shouganai [accepting one’s fate]. If a huge earthquake comes, well, it can’t be helped. For now, they think, it’s good to live in Tokyo.”

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