Abstract
The tsunamis ascending the rivers, were simulated numerically, using the nonlinear shallow water equations. In the present cases, the crest and trough of the incident waves, were not symmetric, rsulting in mass transport into the river, with a gradual increase in the mean water level. When the angle between a main, and a tributary, rivers is narrow, the tsunami height in the latter increased. In the cases determining the tsunami ascending the Kimotsuki River, Kagoshima, Japan, as the still water level was increased, the phase velocity of the tsunami increased. As the incident wave period was increased, the maximum water level in each wave increased, although it decreased owing to the flood channel.
