Abstract:
The planning and design of urban drainage system can not be
successfully conducted without a variety of supporting data
relating to the locality of the actual project as well as
to the entire region that will be benefited or affected by
the project. The drainage design should provide a balanced
combination of natural and man-made drainage elements which
offer an adequate flood protection for urban developments
and minimize drainage impact on receiving waters.
It has been noted that although there has been substantial
progress made in development of design tools, the progress
in the availability and acquisition of supporting data is
lacking. Therefore, this study is concentrated on the
acquisition of supporting data such as climatic condition,
urbanization pattern, topography of land, surface water
availability and socio-economic condition of Bangladesh.
After conducting the survey on the existing drainage system
in the selected towns, the problems were identified and
summarized. Some probable solutions are also proposed to
overcome the problems and difficulties. These will help in
designing and taking decision in the field, in this regard.
A new concept on the shape of drain has been suggested to
construct the drains in flat areas which allows to flow
sullage more efficiently. This shape provides better self
cleansing velocity to the sullage flow. Run-off coefficient
for some selected areas in Bangladesh have been
determined, this may help in assuming run-off co-efficient
for any area. Attempt is being made to identify the cost
effective drain, over ditch or pond to minimize
construction difficulties.
