Selected buildings in Tokyo’s Minato ward will be soon be designated as tsunami-evacuation points. Negotiations are underway between the local city council and 16 companies who own buildings of 10-storeys or higher. Approximately 36.5 million Yen has been set aside in the City’s budget.
Several commercial and residential buildings in Arakawa-ku and Koto-ku have already received designations. While Arakawa-ku provided some assistance with the purchase of emergency supplies and rations, Minato-ku will provide all necessary supplies to the co-operating buildings. They are also considering providing assistance with any upgrades to building security so that they may be accessible to evacuees in an emergency situation.
Minato-ku is targeting buildings that have external stairs. They are not considering apartments at this point as residential buidlings can only hold evacuees in the hallways and stairwells.
According to simulations, if Tokyo experienced a similar earthquake to the 1703 Genroku Earthquake*, which had a magnitude of 8.2 (shindo level of lower to upper 6), it could generate a tsunami of 2.4 meters. The shaking could also cause liquefaction to occur. Under the worst case scenario, the ground could sink by 50 centimetres and the area around on the Yurikamome line would be inundated with 1.5 meters of water.
*The epicentre of the Genroku earthquake was to the east of Oshima Island.
Source: The Tokyo Shimbun, February 18, 2013.