Investigation Regarding Impact on Social Infrastructure Damage Due to Heavy Rainfall

Abstract

 The purpose of this study is to investigate the effects of heavy rainfall increased in recent years on the social infrastructure, and to make a proposal on strengthening design criteria for water management in the future. Damage surveys of the outflow of the railway embankment and river channel blockage by floodwood by Akita and Iwate heavy rainfall on August 9 , 2013 are carried out. The results of the surveys and analysis are as follows; (1) The damages of social infrastructure related to the shortage of cross-sectional area of river, and caused by combined factors consist of topography and land cover of the affected area and sediment, slope and vegetation of upstream area. (2)The cases resulted from lowness of river improvement rate and development priority of small rivers. (3)To reduce damage in the future, it is necessary to accumulate data of the complex factors around the infrastructure at the time of heavy rainfall and to develop the knowledge by analysis.