Recovery After Sanriku Tsunamis in 1896 and 1933, and Transition of Housing Location Before the 2011 Great East Japan Earthquake and Tsunami

Abstract

We need to formulate future strategies for post-disaster recovery policy and planning based on the lessons of past disasters. The Sanriku Coastal Area, a tsunami-prone region located in the northern part of the main island of Japan, survived catastrophic tsunamis in 1896, 1933, and 1960. Before the 2011 Great East Japan Earthquake, the author examined the transition of housing location in the areas in Iwate Prefecture damaged by the 1896 and 1933 Sanriku Tsunamis to understand the situation after the recovery plans conducted before the Second World War.

Firstly, this chapter clarifies that the relocation of housing to higher lands after the 1896 Tsunami decreased the damage sustained by the 1933 Tsunami in some districts, while other areas that failed to relocate housing were severely damaged again. Secondly, focusing on seven districts, chronological aerial photographs provided by the Geospatial Information Authority of Japan demonstrate that the number of houses had gradually increased since 1934 in areas where construction was restricted by the 1934 Post-Tsunami Recovery Plan. The reasons why residents started living in the coastal areas are then presented along with residents’ tsunami risk recognition based on interview surveys. Finally, the damage situation in the seven districts due to the 2011 Great East Japan Earthquake and Tsunami is presented.