Dhaka city water logging hazards: area identification and vulnerability assessment through GIS-remote sensing techniques

Abstract

Water logging is one of the most detrimental phenomena continuing to burden Dhaka dwellers. This study aims to spatio-temporarily identify the water logging hazard zones within Dhaka Metropolitan area and assess the extent of their water logging susceptibility based on informal settlements, built-up areas, and demographical characteristics. The study utilizes integrated geographic information system (GIS)-remote sensing (RS) methods, using the Normalized Difference Vegetation Water and Moisture Index, distance buffer zone from drainage streams, and built-up distributions to identify waterlogged zones with a temporal extent, incorporating social and infrastructural attributes to evaluate water logging effects. These indicators were integrated into an overlay GIS method to measure the vulnerability level across Dhaka city areas. The findings reveal that south and south-western parts of Dhaka were more susceptible to water logging hazards. Almost 35% of Dhaka belongs to the high/very highly vulnerable zone. Greater number of slum households were found within high to very high water logging vulnerable zones and approximately 70% of them are poorly structured. The built-up areas were observed to be increased toward the northern part of Dhaka and were exposed to severe water logging issues. The overall findings reveal the spatio-temporal distribution of the water logging vulnerabilities across the city as well as its impact on the social indicators. An integrated approach is necessary for future development plans to mitigate the risk of water logging.

Impact of Urbanization on Pluvial Flooding: Insights from a Fast Growing Megacity, Dhaka

“…Similarly, the downstream portion of the Baunia khal exhibits a shift in water depth and spatial inundation extent toward greater depth. These findings are consistent with recent research by [31], which shows a high vulnerability to waterlogging around the Baunia Khal depression.…”

“…Ref. [31] focus on the identification of areas prone to water logging The flood dangers in Dhaka were evaluated by [28] using the utilization of geographic information systems (GIS) and remote sensing (RS) imagery. This assessment involved the analysis of flood frequency and flood depth data.Based on the flood extent maps spanning the years 1988 to 2009, a frequency map was generated to illustrate the areas affected by floods.…”

“…Ref. [31] focus on the identification of areas prone to water logging risks in Dhaka city and the assessment of their flood susceptibility. The flood susceptibility map was generated in order to assess the potential for waterlogging.…”

Risk Assessment of Landslide Collapse Disasters along National Highways Based on Information Quantity and Random Forest Coupling Methods: A Case Study of the G331 National Highway

“…The greater the exposure, the higher the risk. The higher the population density, the greater the loss in a collapse disaster, and thus the greater the exposure [37]. Road infrastructure plays a crucial role in the economic development of urban areas.…”

Spatiotemporal Urban Waterlogging Risk Assessment Incorporating Human and Vehicle Distribution

“…The severity of urban waterlogging is closely related to population density. The greater the population density, the greater the number of people affected by waterlogging directly from the disaster [37]. Heat maps use the acquired mobile phone base station to locate the number of users in the area and render the map color by the number of users.…”