Author(s): Hideo Oshikawa; Toshimitsu Komatsu
Linked Author(s): Hideo Oshikawa
Keywords: Dry dam; Overflow; Spillway; Cascade flood control; Climate change adaptation
Abstract: A new concept of flood control called the Cascade method is proposed, in which a series of dams is constructed along a river and upstream dams are allowed to overflow from emergency spillways. Multiple small dry dams (which lack a slide gate in the spillway) are constructed in series rather than a single large dam in order to prevent flood disasters and to preserve the natural environment. Dry dams for flood control have recently been reviewed, planned, and built at some sites in Japan. The Cascade method, which permits upstream dams to overflow and requires the final downstream dam to hold, was compared with a conventional flood control method in a physical experiment under the condition that the dams have the same reservoir capacity. The results show that the Cascade method using multiple dry dams was considerably more effective than the conventional flood control method. In addition, the Cascade flood control could be a useful method for climate change adaptation, because it is implemented by simply modifying the operation of slide gates on existing storage dams constructed in series.
Year: 2013