Characteristics of debris flow hydrographs at the outlet of a basin in different generation conditions

Yusuke YAMAZAKI, Takahisa MIZUYAMA and Yoshitaka KAKIHARA

Debris flow hydrographs at the outlet of a basin were calculated by numerical simulations. In order to discuss the differences among locations of debris flow generation, we set the locations at upper reaches, middle reaches and lower reaches of the basin. In addition to the settings, we set small landslide dams. Debris flow hydrographs generated in the middle reaches showed the sharpest increase of sediment concentration at the end of steep slope in the lower reaches but at the outlet of the basin hydrographs showed moderate increase. Results showed debris flow hydrographs change drastically by locations and their generated locations.