Abstract
The Barato river basin which is situated north of Sapporo City in Hokkaido is characterized by low-lying areas. The prevention and mitigation of flood damage in this basin are mainly controlled by the two gates; the gate of Shibi Canal plays an important role in shutting off the backwater effect of the Ishikari River, while the gate of Ishikari Floodway drains out the inflow from three upstream tributaies of the Barato river as fast as possible. The current gate operations in the Barato river system heavily rely on the intuition of the experienced engineers at the local river office, mainly because decision-making should be done on complicated predictions of inflows to the Barato river, water levels of Ishikari and Barato rivers, and the tide in the river mouth. This paper describes the basic concept of the Fuzzy support system applied to the gate operations in the Barato river basin and some simulation results.
