Unplanned urbanization of Dhaka city: increase of rainfall induced flood vulnerability

Abstract

Dhaka, the capital city of Bangladesh is one of the most populous megacities in the world. As the growth of urban population tacking place at an exceptionally rapid rate, the city is unable to cope with changing situations due to their internal resource constraints and management limitations. In recent years Dhaka City is facing extensive water logging during the monsoon (May to October) as a common and regular problem of the city like water pollution, traffic congestion, air and noise pollution, solid waste disposal, black smoke etc. This research applied remote sensing and GIS techniques to detect the low land status in different time period and the trend of unplanned urbanization that is one of the major causes of water logging in Dhaka City. Remote sensing could provide timely and low-cost information on floods and land use status whereas GIS is an excellent tool in handling information in land management and flood mitigation. Management of drainage system of Dhaka City is presently a challenge for the urban authorities because of rapid growth of population and unplanned development activities. Therefore, a close coordination among urban authorities and agencies and collaboration between public and private sectors is needed for effective management and sustainable operation of urban drainage system. It ascertain the inherent causes of such water logging and its effects on the city life from the perception of authorities of different development organizations, experts and people living in different parts of Dhaka City.