“We are more scared of the power elites than the floods”: Adaptive capacity and resilience of wetland community to flash flood disasters in Bangladesh

Flash-flood disasters pose a serious threat to lives and property. To meet the increasing demand for refined and rapid assessment on flood loss, this study exploits geomatic technology to integrate multi-source heterogeneous data and put forward the comprehensive risk index (CRI) calculation with the fuzzy comprehensive evaluation (FCE). Based on mathematical correlations between CRIs and actual losses of flood disasters in Weifang City, the direct economic loss rate (DELR) model and the agricultural economic loss rate (AELR) model were developed. The case study shows that the CRI system can accurately reflect the risk level of a flash-flood disaster. Both models are capable of simulating disaster impacts. The results are generally consistent with actual impacts. The quantified economic losses generated from simulation are close to actual losses. The spatial resolution is up to 100 × 100 m. This study provides a loss assessment method with high temporal and spatial resolution, which can quickly assess the loss of rainstorm and flood disasters. The method proposed in this paper, coupled with a case study, provides a reliable reference to loss assessment on flash floods caused disasters and will be helpful to the existing literature.

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China National Flash Flood Disasters Investigation and Assessment

10.29007/7zjd ◽

2018 ◽

Author(s):

Xiaolei Zhang ◽

Liang Guo ◽

Ronghua Liu ◽

Qi Liu ◽

Qiuling Yao ◽

...

Keyword(s):

Spatial Distribution ◽

Flood Control ◽

Flash Flood ◽

Site Investigation ◽

Flood Management ◽

Information Support ◽

Future Application ◽

Human Settlement ◽

Rainfall Index ◽

Flood Disasters

National Flash Flood Disasters Investigation and Assessment project is the largest non-engineering projects in water conservancy industry in China, and also the largest scale of general census on disasters’ background in flood management and mitigation fields. Through general census, on-site investigation, field measurement, hydrological analysis and calculation, the spatial distribution, human settlement, underground situations, social and economic impacts, hazard zoning, warning indicators of flash flood disasters were collected, the storm flood characters in mountainous areas were analyzed, the flood control ability of selected villages were assessed, the critical rainfall index of these villages were obtained, and the hazard zones were finally identified, all of which provided a strong information support for flash flood early-warning and forecast and residential safety transfer. This paper systematically introduced the key technical focuses, made a general review on the data and information collected, and discussed the spatial distribution pattern of these elements. Based on these survey data, the characteristics of flash flood disaster prevention areas, the human settlement features and storm flood spatial distribution situation were further analyzed. In the end of this paper, future application and analysis on diversified utilization of national flash flood disasters investigation and assessment results were proposed.

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Community Preparation in Tangse District in Flash Flood Disaster Mitigation

International Journal of Multicultural and Multireligious Understanding ◽

10.18415/ijmmu.v7i3.1500 ◽

2020 ◽

Vol 7 (3) ◽

pp. 368

Author(s):

Martini Martini ◽

Azmeri Azmeri ◽

Didik Sugiyanto

Keyword(s):

Law Enforcement ◽

Research Design ◽

Flash Flood ◽

Disaster Mitigation ◽

Design Data ◽

Data Presentation ◽

Qualitative Research Design ◽

Flood Disasters ◽

Law Enforcement Officials ◽

Knowledge And Attitude

This study aims to determine the Tangse community preparedness in mitigation of flood disasters. The research design used in this study is a qualitative research design . Data analysis is performed using three activities that occur simultaneously, namely data reduction, data presentation, and drawing conclusions or verification, or can also use words to describe facts and observed phenomena. Based on the results of research and discussion, it can be concluded that in terms of the knowledge and attitude of the Tangse community it is already good where the community already knows the signs of flash floods and the environment is vulnerable to disasters. But it is still very lacking in terms of regulations and policies. Regulations that have not been implemented properly, as well as sanctions for illegal loggers involving law enforcement officials.

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Flash flood disasters in Uttarakhand

Disaster Prevention and Management An International Journal ◽

10.1108/09653561011091896 ◽

2010 ◽

Vol 19 (5) ◽

pp. 565-570 ◽

Cited By ~ 5

Author(s):

Ravindra K. Pande

Keyword(s):

Flash Flood ◽

Flood Disasters

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Spatiotemporal clustering of flash floods in a changing climate (China, 1950–2015)

10.5194/nhess-2020-238 ◽

2020 ◽

Author(s):

Nan Wang ◽

Luigi Lombardo ◽

Marj Tonini ◽

Weiming Cheng ◽

Liang Guo ◽

...

Keyword(s):

Flash Flood ◽

Extreme Rainfall ◽

Flash Floods ◽

Scan Statistics ◽

Spatiotemporal Pattern ◽

Precipitation Trend ◽

Wet Season ◽

Extreme Rainfall Events ◽

Space And Time ◽

Flood Disasters

Abstract. The persistence over space and time of flash flood disasters – flash floods that have caused either economical or life losses, or both – is a diagnostic measure of areas subjected to hydrological risk. The concept of persistence can be assessed via clustering analyses, performed here to analyse the national inventory of flash flood disasters in China occurred in the period 1950–2015. Specifically, we investigated the spatiotemporal pattern distribution of the flash flood disasters and their clustering behavior by using both global and local methods: the first, based on the Ripley's K-function, and the second on Scan Statistics. As a result, we could visualize patterns of aggregated events, estimate the cluster duration and make assumptions about their evolution over time, also with respect precipitation trend. Due to the large spatial (the whole Chinese territory) and temporal (66 years) scale of the dataset, we were able to capture whether certain clusters gather in specific locations and times, but also whether their magnitude tends to increase or decrease. Overall, the eastern regions in China are much more subjected to flash flood disasters compared to the rest of the country. Detected clusters revealed that these phenomena predominantly occur between July and October, a period coinciding with the wet season in China. The number of detected clusters increases with time, but the associated duration drastically decreases in the recent period. This may indicate a change towards triggering mechanisms which are typical of short-duration extreme rainfall events. Finally, being flash flood disasters directly linked to precipitation and their extreme realization, we indirectly assessed whether the magnitude of the trigger itself has also varied through space and time, enabling considerations in the context of climatic changes.

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Spatiotemporal clustering of flash floods in a changing climate (China, 1950–2015)

Natural Hazards and Earth System Science ◽

10.5194/nhess-21-2109-2021 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2109-2124

Author(s):

Nan Wang ◽

Luigi Lombardo ◽

Marj Tonini ◽

Weiming Cheng ◽

Liang Guo ◽

...

Keyword(s):

Flash Flood ◽

Extreme Rainfall ◽

Flash Floods ◽

Scan Statistics ◽

Spatiotemporal Pattern ◽

Precipitation Trend ◽

Wet Season ◽

Extreme Rainfall Events ◽

Space And Time ◽

Flood Disasters

Abstract. The persistence over space and time of flash flood disasters – flash floods that have caused either economical losses or loss of life or both – is a diagnostic measure of areas subjected to hydrological risk. The concept of persistence can be assessed via clustering analyses, performed here to analyze the national inventory of flash flood disasters in China that occurred in the period 1950–2015. Specifically, we investigated the spatiotemporal pattern distribution of the flash flood disasters and their clustering behavior by using both global and local methods: the first based on Ripley's K function, and the second on scan statistics. As a result, we could visualize patterns of aggregated events, estimate the cluster duration and make assumptions about their evolution over time, also with respect to the precipitation trend. Due to the large spatial (the whole Chinese territory) and temporal (66 years) scale of the dataset, we were able to capture whether certain clusters gather in specific locations and times but also whether their magnitude tends to increase or decrease. Overall, the eastern regions in China are much more subjected to flash flood disasters compared to the rest of the country. Detected clusters revealed that these phenomena predominantly occur between July and October, a period coinciding with the wet season in China. The number of detected clusters increases with time, but the associated duration drastically decreases in the recent period. This may indicate a change towards triggering mechanisms which are typical of short-duration extreme rainfall events. Finally, being flash flood disasters directly linked to precipitation and their extreme realization, we indirectly assessed whether the magnitude of the trigger itself has also varied through space and time, enabling considerations in the context of climatic change.

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Determination of Adaptive Capacity for Flash Floods in Sri Lankan Context: Colombo City

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.c1004.0193s20 ◽

2020 ◽

Vol 9 (3S) ◽

pp. 19-24

Keyword(s):

Sri Lanka ◽

Adaptive Capacity ◽

Climate Changes ◽

Flash Flood ◽

Secondary Data ◽

Flash Floods ◽

Sri Lankan ◽

Management Actions ◽

Adaptive Index

Sri Lanka has witnessed many natural and anthropogenic disasters that have had a devastating impact on community and the economic welfare of the country. Disaster management actions are required to be taken to reduce disaster risk. Adaptive capacity is one of such measurements that can predict the resilience of the community. Climate changes directly effects on occurrences of disasters, especially on flash floods, which is one of the frequent disasters in Sri Lanka. The present research explained about developing an adaptive index for flash flood occurrences in the Colombo City, Sri Lanka. Secondary data were used to identify indicators of the index as well as to quantify the frequency and severity of the flash flood. Five determinants and 16 indicators were developed for the index by considering all 47 wards of Colombo city. All measurements were weighted by using a questionnaire survey and the results were normalized. Five determinants were mapped based on analyzed data and the highest vulnerability wards were identified. Mahawatte ward has the highest vulnerability followed by Wanathamulla and Bluemendhal. On the other hand, Kotehena East was observed as the lowest vulnerability ward followed by Wellawatte South and Wellawatte North.

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Combining TRIGRS and Massflow Models for the Assessment of Flash Flood Disasters Related to Sediment Supply in Mountainous Watersheds

10.5194/egusphere-egu21-7089 ◽

2021 ◽

Author(s):

Tong Sun ◽

Xiekang Wang ◽

Xufeng Yan

Keyword(s):

Flash Flood ◽

Coupling Effect ◽

Flash Floods ◽

Sediment Supply ◽

Landslide Stability ◽

Sediment Loads ◽

Flood Disasters ◽

Mountainous Watersheds ◽

Mountainous Basin ◽

Landslide Distribution

<p>Abstract: Evaluation of a large number of rainstorm disasters shows that the coupling effect of sediment supply and floodwaters is one predominant cause for the occurrence of flash flood disasters. Rainfall-induced shallow landslides often provide an adequate source of solid materials to recharge moving sediment during flash floods. In this study, we used the TRIGRS model to analyze the rainfall-related landslide stability in a mountainous basin and gain potential landslide volumes as potential sources for sediment loads. Then, with the calculated results of landslides as input, the Massflow model was used to evaluate how the landslides as sediment loads evolved with flows. The results showed that there was a large amount of sediment deposited in the channel, which can be initiated and transported by heavy rainfalls, leading to the destruction of villages at the mouth of gullies. In general, this study offers a strategy of evaluating sediment-coupled flash flood disasters that the TRIGRS can provides the estimate of landslide distribution and volume first and the Massflow provides the estimate of subsequent movement of the solids caused by flash floods.</p>

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The Trend in the Risk of Flash Flood Hazards with Regional Development in the Guanshan River Basin, China

Water ◽

10.3390/w12061815 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1815

Author(s):

Ningyue Chen ◽

Yanjun Zhang ◽

Jinjin Wu ◽

Wenxun Dong ◽

Yixuan Zou ◽

...

Keyword(s):

Economic Development ◽

Regional Development ◽

River Basin ◽

Regional Economy ◽

Flash Flood ◽

Development Planning ◽

Flood Routing ◽

Extreme Risk ◽

Flood Disasters ◽

Risk Zones

The economic development of China’s mountainous areas has been rapid, but the impact of flash floods is often ignored during regional development planning. Therefore, a method needed to be developed to simulate flash flood disasters and analyze the trends in flash flood disasters with regional development. Taking Guanshan River Basin as the research area, we combined the digital elevation model (DEM) with the inflow hydrograph, using the topography-based hydrological model (TOPMODEL). Verified by historical flash flood disasters, the watershed model was built based on the finite volume conservation flood routing model (FLO-2D). Then, we simulated the hazard distribution of flash flood disasters, developed a risk status assessment factor (RSAF) for flash flood disasters and calculated the increased ratio from 2003 to 2018. The results show that in 2003, the total hazard area of flash flood disasters affecting human settlements was 61,121 m2, which increased to 118,404 m2 in 2018. Since 2003, with the development of the regional economy, more residents moved to risk and extreme risk zones; thus, the risk of flash flood disasters also increased. Due to the significant damage caused by the flash flood on 5 August 2012, some of the local residents moved away from the high risk and extreme risk zones, indicating that the risk trend of flash flood hazard was consistent with the regional development of Guanshan River. We provide suggestions for regional economic development planning; the risk assessment for flash flood disasters must be considered to ensure the stable development of the regional economy, and using the RSAF would be efficient.

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