By Floro Mercene
TYPHOONS are a part of life in Japan, with several storms lashing the archipelago every year. The Tokyo Metropolitan Government recently unveiled its first estimate of the capital’s vulnerability to damage from typhoon-related tidal waves as the risks from storm damage continue to increase globally.
One third of central Tokyo could be left under water and nearly 4 million people flooded if a supertyphoon strikes the capital and causes storm surges, a new study warns.
The report assumes a typhoon as powerful as 1934’s Muroto Typhoon, which left more than 3,000 Japanese dead or missing. Such a typhoon has an atmospheric pressure of 910 hectopascals at its center and moves at about 73 kph, which would cause storm surges and river flooding from heavy rain and burst dikes.
According to the report, one-third of the central Tokyo could be inundated by as much as 10 meters of water if a supertyphoon creates high tidal waves in the Kameido district of Koto Ward. In particular, Tokyo’s Eastern zone near the Arakawa River would be flooded for more than a week if rising tidal waves at Tokyo port break through the river’s levees. With Arakawa River, for example, boasting one of the densest populations in its surrounding areas of any river in Japan, extensive flooding would lead to unprecedented fatalities and an economic catastrophe. Should the banks of the Arakawa River break, the damage would be so extensive that it could annihilate the entire capital with the below-sea-level areas in Eastern Tokyo likely to be hit the hardest.
An event this severe could affect as many as 3.95 million people in the city, flooding the business and entertainment districts as well as major rail stations, the study said.
Based on the estimate, the Tokyo Metropolitan Government said it plans to update evacuation measures and review how it disseminates warning messages to its residents
