Class
Article
College
College of Engineering
Faculty Mentor
Jagath Kaluaracchi
Presentation Type
Poster Presentation
Abstract
The Ganges Delta of Bangladesh is a good example of two opposite and extreme hydrological conditions, i.e., floods and droughts. This study attempts to determine the changes in hydro-climatological factors and its consequences on floods and droughts. We analyzed four extreme floods (1988, 1998) and droughts (1999, 2006) events. Rainfall, temperature, evapotranspiration, water level, and flow data are used to assess the hydrological changes. The changes in land area corresponding to normal flooding depth over the past 22 years are also considered. River siltation, drainage congestion, backwater effect, land subsidence, synchronization of high flows from major rivers along with the increase of heavy rainfall found to be the key factors for flood events. Dry season of this area is characterized by a negligible amount of rainfall. Upstream water diversion in Ganges River reduces the dry season flow significantly and has made the study area drought prone. Flow duration curves depict a large variation between high flow thresholds (20%) and low flow threshold (70%) in the Bangladesh part of the Ganges River. The statistically significant increase in temperature and evapotranspiration are also contributing to the drought condition. This study highlights the need for an improved management approach of water resources that can minimize droughts and flooding and associated impacts in this deltaic area.
Location
The South Atrium
Start Date
4-12-2018 10:30 AM
End Date
4-12-2018 11:45 AM
Linkage of Hydro-Climatological Variables to Flood and Drought in the Ganges Delta of Bangladesh
The South Atrium
The Ganges Delta of Bangladesh is a good example of two opposite and extreme hydrological conditions, i.e., floods and droughts. This study attempts to determine the changes in hydro-climatological factors and its consequences on floods and droughts. We analyzed four extreme floods (1988, 1998) and droughts (1999, 2006) events. Rainfall, temperature, evapotranspiration, water level, and flow data are used to assess the hydrological changes. The changes in land area corresponding to normal flooding depth over the past 22 years are also considered. River siltation, drainage congestion, backwater effect, land subsidence, synchronization of high flows from major rivers along with the increase of heavy rainfall found to be the key factors for flood events. Dry season of this area is characterized by a negligible amount of rainfall. Upstream water diversion in Ganges River reduces the dry season flow significantly and has made the study area drought prone. Flow duration curves depict a large variation between high flow thresholds (20%) and low flow threshold (70%) in the Bangladesh part of the Ganges River. The statistically significant increase in temperature and evapotranspiration are also contributing to the drought condition. This study highlights the need for an improved management approach of water resources that can minimize droughts and flooding and associated impacts in this deltaic area.