Massive Storm Surge in Tokyo Could Cause 110-T.-Yen Damage

June 8, 2018

Tokyo- If a massive storm surge happens in Tokyo Bay due to a big typhoon, it would cause a total of 110 trillion yen in damage, the Japan Society of Civil Engineers said Thursday.

Of the total, the direct damage to buildings and other assets is put at 64 trillion yen, and the damage caused by a decline in economic activity over the 14 months from the disaster is estimated at 46 trillion yen, the society said.

The figures are based on the assumption that Tokyo Bay is hit by a storm surge as big as the one that the 1934 Muroto Typhoon caused.

The period to estimate the economic damage was set at 14 months in light of the time required for the reconstruction of areas affected by floods from the Kinugawa, a big river in the Kanto eastern Japan region, in 2015. Tokyo is part of the region.

If Ise Bay in central Japan is hit by a storm surge bigger than the one caused by the 1959 Isewan Typhoon, the direct damage should reach 10 trillion yen and the economic damage 9 trillion yen, the society said.

The society expects 56 trillion yen in direct damage and 65 trillion yen in economic damage if Osaka Bay in western Japan meets with a storm surge as large as the one caused by the 1961 Second Muroto Typhoon.

The society also disclosed estimated direct and economic damage from big floods in the Tokyo, Nagoya and Osaka areas, each put at 62 trillion yen, 25 trillion yen and 13 trillion yen, respectively.

The estimates covered possible floods from the Arakawa in the Tokyo area, the rivers of Shonai, Kiso, Nagara and Ibi in the Nagoya area that eventually flow into Ise Bay, and the Yodo in the Osaka area. Jiji Press