NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-12-201-2012 The 13 August 2010 catastrophic debris flows after the 2008 Wenchuan earthquake, China Xu Q. 1 Zhang S. 2 Li W. L. 1 van Asch Th. W. J. 3 State key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, China Dept. of Civil and Environment Engineering, The Hong Kong University of Science and Technology, Hong Kong, China Dept. of Physical Geography, Utrecht University, P.O. Box 80115, 3508 TC, Utrecht, The Netherlands 19 01 2012 12 1 201 216 Copyright: © 2012 Q. Xu et al. 2012 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/articles/12/201/2012/nhess-12-201-2012.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/12/201/2012/nhess-12-201-2012.pdf

From 12 to 14 August 2010, heavy rainstorms occurred in the Sichuan province in SW China in areas which were affected by the 2008 Wenchuan Earthquake, inducing catastrophic debris flows. This disaster is named as "the 8.13 debris flows". The results of the research presented in this paper show that the 8.13 debris flows are characterized by a simultaneous occurrence, rapid-onsets, destructive impacts, and disaster chain effects. They are located along the seismic fault, because the source materials mainly originate from loose deposits of landslides which were triggered by the Wenchuan Earthquake. The presence of large amounts of these loose materials on the slopes and the development of high intensity rainfall events are the main causes for the formation of these debris flows. The study of the 8.13 debris flows can provide a benchmark for the analysis of the long-term evolution of these debris flows in order to make proper engineering decisions. A flexible drainage system is proposed in this paper as a preventive measure to mitigate the increasing activity of these debris flows in the earthquake-affected area.

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