Articles | Volume 19, issue 9
https://doi.org/10.5194/gmd-19-3709-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-19-3709-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Development and technical paper
| 
08 May 2026
Development and technical paper |
| 08 May 2026
| 08 May 2026
Flood volume allocation method for flood hazard mapping using river model with levee scheme
Muhammad Hasnain Aslam
CORRESPONDING AUTHOR
SIT Research Laboratories, Shibaura Institute of Technology, Tokyo, Japan
Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
Yukiko Hirabayashi
Department of Civil Engineering, Shibaura Institute of Technology, Tokyo, Japan
Dai Yamazaki
Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
Gang Zhao
School of Environment and Society, Institute of Science Tokyo, Tokyo, Japan
Yuki Kita
Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
Do Ngoc Khanh
SIT Research Laboratories, Shibaura Institute of Technology, Tokyo, Japan
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Short summary
We present a simple method that turns coarse flood volume estimates into local flood depth maps by using the shape of the land and mapped levee zones. Used with a large-scale river model, it keeps total water volume consistent while spreading water realistically inside and outside levees. Tests show levees often confine water and cut flood volume by about 10 %–15 % for many event sizes. The method reveals place-to-place differences in protection and yields clearer hazard maps for planning.
We present a simple method that turns coarse flood volume estimates into local flood depth maps...
