A Sabo dam is constructed to protect the infrastructure of our lives, but debris flow containing large driftwood have lately been occurring, and large driftwood are flowing into our living areas. The driftwood flow over an existing Sabo dam, and it is necessary to reinforce to the Sabo dam given trapping effect. Therefore, the hangover-type driftwood catchment is proposed with reference of driftwood disaster. However, the external load evaluation for the design is unclear. The study experimentally elucidates the external loads of hangover-type driftwood catchments given to an existing Sabo dam. The results showed that the load was affected due to the amount of initial sediment and driftwood volume.
