| Rivers in Bangladesh are
morphologically highly dynamic. The main rivers are
braided, and form islands or char in between the braiding
channels. These chars, of which any are inhabited, "move
with the flows" and are extremely sensitive to changes in
the river conditions. Erosion processes are highly
unpredictable, and not compensated by accretion. These
processes also have dramatic consequences in the lives of
people living in those areas. A four year study concluded
in 1991 reported that: out of the 462 administrative units
in the country, 100 were subject to some form of riverbank
erosion, of which 35 were serious, and affected about 1
million people on a yearly basis (REIS, 1991).
A study by EGIS (1997), analyzing remote sensing
images from 1973 to 1996 of the 240 km long Brahmaputra-Jamuna River between the Indian border, and
the confluence with the Ganges concluded that the river
has been widening at an average rate of about 130 m per
year. This corresponded to a loss of about 70,000 ha in 23
years, while only 11,000 ha had been accreted. The same
EGIS study concluded that the observed erosion during the
flood years 1987 and 1988 was 8,000 ha per year against an
average of 3,000 ha per during the mentioned 23 year
period - this gives some indication of how sensitive these
processes are. Changes in the river flows and sediment
transport due to multi- dimensional impacts of climate
change are expected to increase the dynamics of these
rivers even more. While the consequences are highly
uncertain, they give rise to major concern especially
given the related loss of land and property.
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