Long-term monitoring of sediment runoff for an active sediment control in Joganji River

There were huge sediment yielding and deposition due to debris flows by breaking natural landslide dams which formed earthquake in 1858 at upstream reach of Joganji River. Sediment transportation is still active flow with bedload rainfall, though a lot erosion control have been constructed. Continuously measuring runoff for long term along main river necessary evaluate the propagation after events management basin using well hydrological information. Appropriate tools are selected applied monitoring area managed Tateyama Mountain Area Sabo Office River, Reid-type slot sampler, robust-type hydrophone velocity meter on bed turbidity washload. Monitored data concentratedly collected office apply risk movement heavy rainfall so on. Several typical problems solved shown because it passed around twenty years since started, those reported present study.