Estimation of “Lost Material Stock” in the Great East Japan Earthquake

Abstract

Following the disaster in Northeast Japan, it is important to obtain an estimation of the scale of lost buildings and infrastructures’ material stock. Therefore the amount of materials necessary for future reconstruction as well as the subsequent waste flow generation could be estimated and, more importantly, proper policies could be proposed for the recovery of stricken areas. In this study, from detailed residential maps, we built a material stock database throughout Japan. And, by extracting material stock with the area affected by the tsunami, we built a lost material stock database. The amount of material stock in the area hit by the tsunami was calculated to be about 29 million tons. Superstructure of buildings is about 10 million tons, and the foundation of buildings is about 19 million tons. The problem lies in the amount of debris, and also the amount of materials in the ground. In this paper, lost material stock of each municipality, and the distribution of lost material stock in Ishinomaki and Higashimatsushima are described.