THE EFFECT OF GROINS INSTALLATION ON THE RESTORATION OF GRAVEL BEDIN THE TEDORI RIVER

Although gravel beds create a good environment for river ecosystem, the reduction of gravel supply from upper stream caused serious bed degradation problem in recent years. Under these circumstances, gravel bed area gradually disappeared and the exposure of soft rock has progressed. Once the soft rock appeared, it is very difficult to recover the gravel bed. Therefore it is very important to establish gravel bed restoration method. In the Tedori River, groins using natural stones were experimentally installed to restore the gravel bar and further river restoration project to install new groins will be carried out. Therefore, in this paper, the effect of the groins is examined using two-dimensional flow analysis. Simulation results show that groins installation has an effect on the restoration of gravel bed.