Flood characterisation of the Haor region of Bangladesh using flood index

Abstract

The paper presents the flood characterisation of the Haor region in the north-east of Bangladesh. The region consists of a system of Haors, each of which is a saucer-shaped depression and interconnected by a river system. A portion of the Haor area, known as the deeply flooded area, consisting of about 15 Haors, was chosen as the study area. A 1D2D model, with one-dimensional model for the rivers and a two-dimensional model for the Haors, was developed. Flood hydrograph characteristics such as the rising curve gradient, flood magnitude ratio (with respect to the average discharge) and time to peak were assessed for different river floods. Using these characteristics an integrated flood index (FI) was developed. The FI is an aggregated indicator based on the flood hydrograph characteristics and indicates the relative overall severity of a flood. The spatial and temporal variations of the index were investigated as well. The computed FI at different locations of the region and for different flood hazard frequencies provide a broad understanding of the flooding characteristics of the region. The developed methodology can also be applied to other river basins to analyse flooding risk provided some historical flood data are available.

Resilience to flash floods in wetland communities of northeastern Bangladesh

“…For example, flash floods of 2007 in northeastern Bangladesh affected ~10% area of the country but killed several hundred people and affected livelihoods in Haor communities (Hashem, 2016). Over the last few decades, numerous studies were conducted to identify hydrological and climatic drivers of flooding in Bangladesh (Brammer, 1990;Mirza et al, 2003;Suman and Bhattacharya, 2015). On the other hand, a few studies (Khan, 2015;Parvin et al, 2016) looked at social vulnerability to flooding and resilience of communities and individuals, particularly poor people, living in floodplains and coastal regions, who may or may not receive direct support from the government of Bangladesh during disasters.…”

A geospatial assessment of flood hazard in north‐eastern depressed basin, Bangladesh

“…Monsoon winds brought rainfall in the Meghalaya catchment and subsequently increased the water level of all stream networks and the Surma River in July 2019 (Figure 9). Flood extension thus depended on the occurrence of rainfall in the upstream and peak discharge of the river water in the case of monsoon flooding (Suman & Bhattacharya, 2015). In terms of water extension, we discovered that pre‐monsoon flash floods caused a rapid extension of waterbodies in the research area around April, 2017 (Figure 5).…”

Simulating the impact of piers on hydrodynamics and pollutant transport: A case study in the Middle Yangtze River

“…MIKE21 FM, created by the Danish Hydraulics Institute, has been widely applied in scientific and environmental consulting communities [ 17 , 18 ]. We performed simulations using the MIKE21 FM-coupled HD and transport module (TR).…”

“…The root mean square error (RMSE) and Nash-Sutcliffe efficiency coefficient (NSE) were used to assess the accuracy of the model [ 18 , 21 ]. 5 observed hydrological data set (including water level and velocity) at the fixed cross-sections in 2009–2011 were collected for HD module, 2 were for calibrating the model and 3 for verification.…”