Flood forecasting and warning system in Bangladesh

摘要

Bangladesh is one of the largest deltas in the world having a very flat topography. Three major rivers, the Ganges, the Brahmaputra and the Meghna having a total catchments area of about 1.7 million sq.km. Pass through this country. 93% of the catchments area of these rivers lies outside the country in India, China, Nepal and Bhutan. The country has an average rainfall of about 2300 mm, the range being 1500 mm to 5000 mm. Bangladesh has also an unique coast line, conical in shape, which causes a higher sea level during monsoon months. Due to the unique topography, river system and rainfall pattern flood occurs in Bangladesh almost every year and devastating ones in every 5 to 10 years time. In its management of flood, Bangladesh has taken many structural and non- structural measures. One of the main non-structural measures is the flood forecasting and warning system. Flood Forecasting and Warning System of the country are in the process of continuous advancement since 1970's. Starting with a very simple way of flood forecasting, it has now developed most advanced real time flood forecasting system with Mike'00 Hydrodynamic Model, which is interactive with the GIS and has the capability of showing flood inundation with Digital Elevation Model (DEM). The paper will deal with development of flood forecasting since 1970's and depict the latest system of flood forecasting and warning system in the country.