Abstract
The new flood control method called as 'Cascade method' permitting a dam to overflow from an emergency spillway around an upstream region with plural dry dams set in series in a river basin was confirmed by the experiment with a model. In addition, it also became clear that the shape of a flood hydrograph into a most upstream dam reservoir influences effects of the Cascade method greatly. Furthermore, the flood control capability of another new type of a dry dam to encourage water-utilization was also clarified. The new type has an outlet work for flood control with a slide gate which can be closed automatically depending on hydraulic pressure or buoyancy. The physical experiment demonstrated that the new type of dry dams constructed in series with such a gate strengthens not only functions for irrigation but also a flood control capability of the Cascade method.
