1. Organization for Regional Co-Creation of Sustainable Communities and Watershed Disaster Resilience, Prefectural University of Kumamoto, 3-1-100 Kumamoto, Higashi-ku, Kumamoto 862-8920, Japan
2. River Planning Department, Nippon Koei Co., Ltd., 5-4 Kojimachi, Chiyoda-ku, Tokyo 102-8539, Japan
3. Faculty of Architecture and Civil Engineering, Kyushu Sangyo University, 2-3-1 Matsukadai, Higashi-ku, Fukuoka 813-8503, Japan
4. Laboratory for Watershed Disaster Resilience, Prefectural University of Kumamoto, 3-1-100 Kumamoto, Higashi-ku, Kumamoto 862-8920, Japan