Author(s): Kenichiro Kobayashi
Linked Author(s): Kenichiro Kobayashi
Keywords: Shallow water flow model basin flood control paddy field dam supercomputer paddy polygon
Abstract: Recently, so-called river basin flood control has begun in Japan and is becoming more active. All stakeholders living in the river basin consider flood control in the river basin to be their own matter, and the goal is to create a safe and secure society that transcends organizational barriers. One of the features of the project is the operation of rice field dams, which are carried out in cooperation with river managers and agricultural managers, and attempts have begun to provide rice paddies as retarding ponds in the event of floods. Until recently, rice field information in Japan was obtainable as square rice fields in land use data with a resolution of several hundred meters. However, the Ministry of Agriculture, Forestry and Fisheries recently published nationwide rice field polygon data that shapes the banks of rice fields, so this time we analysed using this data. Specifically, all the farmland polygons of a Japan city or Kawagoe city, Saitama Prefecture (the city area of 110 km2, population 350,000) were used and the flow movement of the entire city was modelled with a resolution of 2 m using a shallow water equation. At this time, a paddy field dam was expressed by raising the elevation of the farmland bank by 0.3 m. The number of computational nodes is 7989×6746=53,893,794, thus a supercomputer was used. The research activities will be briefly presented.
Year: 2025