A01
Flood Hazard Mapping Using A Nested Flood Simulation Model in Gaibandha District, Bangladesh
Arpan PAUL Mashfiqus SALEHIN
Masakazu HASHIMOTO, Kenji KAWAIKE, Tomonori DEGUCHI, Arpan PAUL, Mashfiqus SALEHIN, Hajime NAKAGAWA
The purpose of this study is to produce a hazard map in Gaibandha district in Bangladesh. To analyze the flood inundation, 2-dimensional unsteady flow model was applied. In addition, flood frequency analysis was conducted using the annual peak discharge values of Jamuna River during 1960-2011, and the hydrograph pattern of 1987 that shows the worst scenario of flooding was used to simulate the flood in the case of each return period. As a result, a flood hazard map was produced, and the flood extent, depth, the area that has high flow velocity, the location of hospitals and embankments were delineated on the map. (103 words).
F n b c edc a dc b w cC a c C c n c w 022, 2 ) 5 1 )1, () 1 1 15 ( c w a ad c l cC C a w c d c os b c e c s i n a c b a ad a c s i n W g w cC c n r ( ) (Fig. 1) l ^ ^ ^ ^ ^ 0 50 km 0 300 km
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Bahadurabadobs. Dewanganjobs. Kaunia obs.Fig. 1 Map of Bangladesh (Right: whole part of Bangladesh, Left: target area. Yellow part indicates the Gaibandha District)
0 20000 40000 60000 80000 100000 04 05 06 07 08 09 10 11 12 Discharge (m 3/s) Time (month) 1987 original 1987(2.33 year) 1987(10 year) 1987(20 year) 1987(50 year) 1987(100 year)
Fig. 2 Hydrographs of each return period in the Jamuna River
( a, 1980) ( ) s i n (SRTM) 30 ( 900m) 6 ( 180m) 2m n w Sentinel-1A c 1960 a2011 2.33, 10, 20, 50, 100 d d c a 1987, 1988, 1998, 2004 a c 1987 g d d c n (Fig. 2) Fig.3 100 0.5m/s F c ( ) c Cda W c c b c b c c c c adc c w c c eb W C n 100 w c t adc , , (1980): , , Vol.23 B, pp.305-317. , , , (2015): w c s i n ,
B1( ), Vol.71, No.4, pp.I_1459-I_1464.
" u " u " u Legend
High flow velocity area_>=0.5 Embankments " u Hospitals Rail Road Flood depth (m) 0.0 - 0.5 0.5 - 1 1.0 - 1.5 1.5 - 2 2.0-Elevation (m) High : 1339 Low : 7 02.55 10 15 20km
