Journal of Natural Disaster Science

EMBANKMENT FAILURE AND SEDIMENTATION OVER THE FLOODPLAIN IN BANGLADESH: FIELD INVESTIGATIONS AND BASIC MODEL EXPERIMENTS

Md. Zahurul ISLAM
Guest Scholar, Disaster Prevention Research Institute, Kyoto University Assistant Professor, Institute of Flood Control & Drainage Research, Bangladesh University of Engineering & Technology
Kenji OKUBO
Research Associate, Disaster Prevention Research Institute, Kyoto University
and
Yoshio MURAMOTO
Professor, Department of Civil Engineering, Faculty of Engineering, Kyoto University

(Received 22 April, 1994 and in revised form 21 September, 1994)

Abstract

Bangladesh, a country of rivers heavily charged with suspended sediments, experiences frequent flood disasters. Every year hundreds of embankments are destroyed or partially damaged by devastating flood waters, resulting in sedimentation over the floodplains. An extensive investigation showed that only ten breaches in eight flood embankments caused sediment deposition on the floodplain of more than 16 million cubic meters, resulting in damage to 66,700 hectares of agricultural crops.

Results of model experiments were compared with field observations. Sediment volume and thickness over the floodplain were shown to increase with the length of the breach in the embankment, sediment inflow, and time. Model sedimentation was greater in the floodplain where there was assumed to be jute fields than as opposed to rice fields.

Key words

flood disaster, Bangladesh, embankment failure, sedimentation, floodplain, model experiment