Bull Earthquake Eng (2013) 11:205–239 DOI 10.1007/s10518-012-9348-9 ORIGINAL RESEARCH PAPER Tsunami damage to coastal defences and buildings in the March 11th 2011 M w 9.0 Great East Japan earthquake and tsunami Stuart Fraser · Alison Raby · Antonios Pomonis · Katsuichiro Goda · Siau Chen Chian · Joshua Macabuag · Mark Offord · Keiko Saito · Peter Sammonds Received: 8 September 2011 / Accepted: 8 March 2012 / Published online: 27 March 2012 © Springer Science+Business Media B.V. 2012 Abstract On March 11th 2011 a M w 9.0 mega-thrust interface subduction earthquake, the Great East Japan Earthquake, occurred 130 km off the northeast coast of Japan in the Pacific Ocean at the Japan Trench, triggering tsunami which caused damage along 600 km of coastline. Observations of damage to buildings (including vertical evacuation facilities) and coastal defences in T¯ ohoku are presented following investigation by the Earthquake Engi- neering Field Investigation Team (EEFIT) at 10 locations in Iwate and Miyagi Prefectures. Observations are presented in the context of the coastal setting and tsunami characteris- tics experienced at each location. Damage surveys were carried out in Kamaishi City and Kesennuma City using a damage scale for reinforced concrete (RC), timber and steel frame S. Fraser (B ) Massey University/GNS Science Joint Centre for Disaster Research, Massey University Wellington Campus, P.O. Box 756, Wellington, New Zealand e-mail: S.A.Fraser@Massey.ac.nz A. Raby School of Marine Science and Engineering, Plymouth University, Plymouth, UK A. Pomonis · K. Saito Cambridge Architectural Research Limited, Cambridge, UK K. Goda Department of Civil Engineering/Cabot Research Institute, University of Bristol, Bristol, UK S. C. Chian Department of Engineering, University of Cambridge, Cambridge, UK J. Macabuag Building Design Partnership, London, UK M. Offord Sellafield Ltd, Warrington, UK P. Sammonds Institute for Risk & Disaster Reduction, University College of London, London, UK 123