FIELD SURVEY OF THE 2011 OFF THE PACIFIC COAST OF TOHOKU EARTHQUAKE TSUNAMI DISASTER AND FUTURE TSUNAMI PROTECTION

On March 11, 2011, a large earthquake of magnitude 9.0 took place, generating a tsunami that caused a severe damage to the east coast of Japan. Field surveys were performed to know tsunami inundation heights and disasters in Iwate, Miyagi, Fukushima, Ibaraki and Chiba prefectures. The results of these surveys are reported. Inundation heights were more than 10 m in the north part of Miyagi, 5 to 10 m along the coast of Sendai Bay and around 5 m in Ibaraki and Chiba. Buildings, including reinforced concrete structures, were washed away and ships were stranded in land. Coastal structures such as dikes and coastal forests also suffered extensive damage. Possible evacuation measures are also discussed based on the observations.