River Modelling for Flood Risk Map Prediction: A Case Study of Kayu Ara River Basin, Malaysia

AbstractThe study of flood risk involves the knowledge of the spatial variability in the characteristics of the vegetation cover, terrain, climate and changes induced by the intervention of humans in watersheds. The increased needs of the actors in land management mean that static maps no longer meet the requirements of scientists and decision-makers. Access is needed to the data, methods and tools to produce complex maps in response to the different stages of risk evaluation and response. The availability of very high spatial resolution remote sensing data (VHSR) and digital terrain model (DTM) make it possible to detect objects close to human size and, therefore, is of interest for studying anthropogenic activities. The development of new methods and knowledge using detailed spatial data, coupled with the use of GIS, naturally becomes beneficial to the risks analysis. Indeed, the extraction of information from specific processes, such as vegetation indices, can be used as variables such as water heights, flow velocities, flow rates and submersion to predict the potential consequences of a flood. The functionalities of GIS for cartographic overlay and multi-criteria spatial analysis make it possible to identify the flood zones according to the level of risk from the flood, thus making it a useful decision-making tool.This study was carried out on the territory of watersheds in the Annaba region, East of Algeria. The choice was guided by the availability of data (satellites images, maps, hydrology, etc.) and hydrological specificities (proximity to an urban area). The adopted model is divided into two parts. The first part is to establish a methodology for the preservation of wetland biodiversity and the protection of urban areas against floods. Thanks to the multi-criteria spatial analysis and the functionalities of the GIS, we established a flood risk map for the watershed defined above. The result was satisfactory compared with the field reality. The second part of the model consisted of the integration of cadastral information with the flood risk map obtained in the first part of our research.The primary objective of this mapping is to contribute to the development of flood risk management plans (in the sense of risk reduction). The mapping stage also provides quantitative elements to more accurately assess the vulnerability of a territory.

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Adapting Rainfall Variability to Flood Risk: A Case Study of the Ghaggar River Basin

Journal of the Geological Society of India ◽

10.1007/s12594-021-1873-1 ◽

2021 ◽

Vol 97 (11) ◽

pp. 1347-1354

Author(s):

Sanjoy Gorai ◽

Dwarikanath Ratha ◽

Amit Dhir

Keyword(s):

River Basin ◽

Flood Risk ◽

Rainfall Variability

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Assessing the Governance Context Support for Creating a Pluvial Flood Risk Map with Climate Change Scenarios: The Flemish Subnational Case

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi9070460 ◽

2020 ◽

Vol 9 (7) ◽

pp. 460 ◽

Cited By ~ 1

Author(s):

Cesar Casiano Flores ◽

Joep Crompvoets

Keyword(s):

Climate Change ◽

Flood Risk ◽

Steering Committee ◽

Provincial Government ◽

Climate Change Scenarios ◽

Risk Map ◽

The Creation ◽

Risk Maps ◽

Flood Risk Map ◽

Subnational Governments

Climate change has increased pluvial flood risks in cities around the world. To mitigate floods, pluvial risk maps with climate change scenarios have been developed to help major urban areas adapt to a changing climate. In some cases, subnational governments have played a key role to develop these maps. However, governance research about the role of subnational governments in geospatial data development in urban water transitions has received little attention. To address this gap, this research applies the Governance Assessment Tool as an evaluative framework to increase our understanding of the governance factors that support the development of pluvial flood risk maps at the subnational level. For this research, we selected the region of Flanders in Belgium. This region is considered among the frontrunners when it comes to the creation of a pluvial flood risk map with climate change scenarios. Data have been collected through in-depth interviews with steering committee actors involved in the development process of the map. The research identified that the current governance context is supportive of the creation of the flood risk map. The government of Flanders plays a key role in this process. The most supportive qualities of the governance context are those related to the degree of fragmentation (extent and coherence), while the less supportive ones are those related to the “quest for control” (flexibility and intensity). Under this governance context, government actors play the primary role. The Flemish government led the maps’ creation process and it was supported by the lower governmental levels. As the provincial government was an important actor to increase local participation, collaboration with private and non-governmental actors in the steering committee was more limited. The financial resources were also limited and the process required a continuous development of trust. Yet, the Flemish Environmental Agency, with the use of technology, was able to increase such trust during the process.

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Integrating Flood Risk, River Basin Management and Adaptive Management: Gaps, Barriers and Opportunities, Illustrated by a Case Study from Kristianstad, Sweden

International Journal of Water Governance ◽

10.7564/13-ijwg30 ◽

2015 ◽

Cited By ~ 1

Keyword(s):

Adaptive Management ◽

River Basin ◽

Flood Risk ◽

River Basin Management ◽

Basin Management ◽

Barriers And Opportunities

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Flood Risk Index for Land-Use Changes: Case Study of Pakpanang River Basin

Engineering Journal ◽

10.4186/ej.2020.24.5.25 ◽

2020 ◽

Vol 24 (5) ◽

pp. 25-40

Author(s):

Chonlatid Kittikhun ◽

Sitang Pilailar ◽

Suwatana Chittaladakorn ◽

Eakawat Jhonpadit

Keyword(s):

Land Use ◽

River Basin ◽

Land Use Planning ◽

Flood Risk ◽

Urban Areas ◽

Risk Index ◽

Land Use Changes ◽

Flood Depth ◽

Arc Gis

Flood Risk Index (FRI) is the multi-criteria linked with the factors of vulnerability; exposure, susceptibility, and resilience. In order to establish local FRI, crucial local information have to be accumulated. However, under the limitation of land-use data, particular techniques were applied in this study. CA Markov model was used to analyze the past missing land-use data and, also forecast the future land-use of Pakpanang river basin under conditions of plan and without plan. The ratio changes of forest, agriculture, wetland and water, and urban areas were considered. Then, the result of LULC spatial-temporal changes was then applied to Hec-HMS and Hec-Ras , with Arc GIS extension of Hec-GeoHMS and Hec-GeoRas software, in order to evaluate the flood hydrographs and flood severity in three municipalities corresponding to 100-year return period rainfall. Afterward, the FRI of Pakpanang, Chianyai, and Hua-sai, which ranges from 0 to 1, were evaluated by using the modified FRI equations. It was found that sensitivity analysis in the area of forest on flood depth and inundation areas is incoherent. Nevertheless, without land-use planning, the changes in these three cities cause higher flood risk, where Chianyai is the riskiest as the FRIE is 0.58. Further consideration of FRIE and FRIP proportion that reveals the FRI deviation indicates that to reduce flood risk, Chianyai would need the most resources and highest effort comparison to Pakpanang and Hua-sai.

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