Assessing Permeability Controls and Flood Risks Related to Urban Impervious Surface Expansion: A Case Study of the Southern Part of Kunming City, China

Abstract Because of climate change and rapid urbanization, urban impervious underlying surfaces have expanded, causing Chinese cities to become strongly affected by flood disasters. Therefore, research on urban flood risks has greatly increased in the past decade, with studies focusing on reducing the risk of flood disaster. From 2012 to 2020, the impervious underlying surface has increased, and the permeable underlying surface has decreased annually in Kunming City. This study was conducted to investigate the impact of continuous changes in the urban underlying surface on flood disasters in the Runcheng area south of Kunming City from 2012 to 2020. We constructed a two-dimensional flood model to conduct flood simulations and flood risk analysis for this area. The relationship between the permeability of the underlying surface and urban flood risk was simulated and analyzed by varying the urban underlying surface permeability (30%, 35%, 40%, 45%, 50%, 55%, and 60%). The simulation results indicate that the urban flood risk increased with increases in the impervious underlying surface, with a threshold permeability of 35%. Once the permeability of the urban underlying surface decreased to below 35%, the flood risk increased rapidly. We demonstrated the impact of the urban underlying surface permeability on the risk of urban flood disasters, which is useful for urban planning decisions and urban flooding risk controls.

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Predicting Future Urban Flood Risk Using Land Change and Hydraulic Modeling in a River Watershed in the Central Province of Vietnam

Remote Sensing ◽

10.3390/rs13020262 ◽

2021 ◽

Vol 13 (2) ◽

pp. 262

Author(s):

Huu Duy Nguyen ◽

Dennis Fox ◽

Dinh Kha Dang ◽

Le Tuan Pham ◽

Quan Vu Viet Du ◽

...

Keyword(s):

Climate Change ◽

Land Cover ◽

Flood Risk ◽

Coastal Region ◽

Flood Plain ◽

Hydraulic Modeling ◽

Land Change ◽

Urban Flood ◽

The Impact ◽

Urban Flood Risk

Flood risk is a significant challenge for sustainable spatial planning, particularly concerning climate change and urbanization. Phrasing suitable land planning strategies requires assessing future flood risk and predicting the impact of urban sprawl. This study aims to develop an innovative approach combining land use change and hydraulic models to explore future urban flood risk, aiming to reduce it under different vulnerability and exposure scenarios. SPOT-3 and Sentinel-2 images were processed and classified to create land cover maps for 1995 and 2019, and these were used to predict the 2040 land cover using the Land Change Modeler Module of Terrset. Flood risk was computed by combining hazard, exposure, and vulnerability using hydrodynamic modeling and the Analytic Hierarchy Process method. We have compared flood risk in 1995, 2019, and 2040. Although flood risk increases with urbanization, population density, and the number of hospitals in the flood plain, especially in the coastal region, the area exposed to high and very high risks decreases due to a reduction in poverty rate. This study can provide a theoretical framework supporting climate change related to risk assessment in other metropolitan regions. Methodologically, it underlines the importance of using satellite imagery and the continuity of data in the planning-related decision-making process.

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Special Issue on Actions Toward Futuristic Urban Flood Risk Research and Management

Journal of Disaster Research ◽

10.20965/jdr.2021.p0309 ◽

2021 ◽

Vol 16 (3) ◽

pp. 309-309

Author(s):

Yoshihiro Shibuo ◽

Kenji Kawaike ◽

Hiroaki Furumai

Keyword(s):

Climate Change ◽

Risk Management ◽

Flood Risk ◽

Flood Risk Management ◽

Special Issue ◽

Private Companies ◽

Urban Flood ◽

Pluvial Flooding ◽

The Impact ◽

Urban Flood Risk

As rainfalls exceeding the designed level have increased, so has damage associated with pluvial flooding. Typhoon Hagibis, which swept Japan in 2019, left 140 municipalities in 15 prefectures scarred from flooding. The sewage networks damaged by the typhoon affected civic life by paralyzing urban functions, raising concerns in urban flood risk and management. Increases in heavy rainfall events associated with global climate change are expected to increase damage from pluvial flooding, thereby necessitating reviews of current urban flood risk management for the purpose of making further improvements against future threats. As we enter an era of frequent urban flooding, it is vitally important that we prepare for urban flood risk management by sharing scientific and technological knowledge among academics, private companies, and administrators. In this context, the current issue is a compilation of contemporary research studies in academia, technological advances in private companies, and practical applications in public administrations in Japan. The works include: the application of urban flood modeling in safe evacuation strategies, the assessment of economic loss, and the impact of climate change; state of the art technologies for urban flood management with the Internet of Things (IoT) and Internet Communication Technology (ICT), Unmanned Aerial Vehicles (UAV), and the next generation of weather radars; and best practices for flood countermeasures, based on knowledge and experience from historical flooding and applied in prefectural governments and local municipalities. We are grateful to all the authors and reviewers who contributed to this special issue, and we hope that it may internationally enhance knowledge-exchange in preparation for growing urban flood risks.

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Assessing the Impact Index of Urbanization Index on Urban Flood Risk

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b1571.078219 ◽

2019 ◽

Vol 8 (2) ◽

pp. 509-516

Keyword(s):

Land Use ◽

Flood Risk ◽

Flood Hazard ◽

Risk Index ◽

Flood Management ◽

Management Approach ◽

Rapid Urbanization ◽

Urban Flood ◽

Tapi Basin ◽

The Impact

The process of urbanization has changed overall Land use/Land cover patterns which are being attributed to flooding and resulting in the economic damages from flooding events. This current study aims to evaluate the implication of spatiotemporal changes of LULC Pattern on the flood risk of Surat city (Gujarat, India), Lower Tapi Basin. The Topographical maps and satellite imagery of Resources-1 of the year 1968 and the year 2006 respectively are used for analyses the urbanization index. As the flood risk is a combination of flood hazard, and vulnerability of the urbanized area, flood losses are expected to rise due to change in each of these aspects. The remote sensing and spatial analysis tools of Geographic Information System (GIS) have been used to statistically examine the flood risk index along with their different land-use scenarios. It has been observed that other than natural processes, rapid urbanization obstructions are being considered as one of the main drivers of flood risk aggravation, and if so, it has made essential for the implementation of flood management approach at the top priority for reducing the risk of flood.

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Urban flood risk warning under rapid urbanization

Environmental Research ◽

10.1016/j.envres.2015.02.028 ◽

2015 ◽

Vol 139 ◽

pp. 3-10 ◽

Cited By ~ 82

Author(s):

Yangbo Chen ◽

Haolan Zhou ◽

Hui Zhang ◽

Guoming Du ◽

Jinhui Zhou

Keyword(s):

Flood Risk ◽

Rapid Urbanization ◽

Urban Flood ◽

Risk Warning ◽

Urban Flood Risk

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Urban Resilience of Shenzhen City under Climate Change

Atmosphere ◽

10.3390/atmos12050537 ◽

2021 ◽

Vol 12 (5) ◽

pp. 537

Author(s):

Weiwei Shao ◽

Xin Su ◽

Jie Lu ◽

Jiahong Liu ◽

Zhiyong Yang ◽

...

Keyword(s):

Climate Change ◽

Flood Risk ◽

Extreme Precipitation ◽

Chinese Government ◽

Urban Flood ◽

Shenzhen City ◽

Taylor Diagram ◽

The Future ◽

The Impact ◽

Urban Flood Risk

The Chinese government attaches great importance to climate change adaptation and has issued relevant strategies and policies. Overall, China’s action to adapt to climate change remains in its infancy, and relevant research needs to be further deepened. In this paper, we study the future adaptive countermeasures of Shenzhen city in the Pearl River Delta in terms of climate change, especially urban flood risk resilience. Based on the background investigation of urban flood risk in Shenzhen, this paper calculates the annual precipitation frequency of Shenzhen from 1953 to 2020, and uses the extreme precipitation index as a quantitative indicator to analyze the changes in historical precipitation and the impact of major flood disasters in Shenzhen city in previous decades. Based on the six kinds of model data of the scenario Model Inter-comparison Project (MIP) in the sixth phase of the Coupled Model Inter-comparison Project (CMIP6), uses the Taylor diagram and MR comprehensive evaluation method to evaluate the ability of different climate models to simulate extreme precipitation in Shenzhen, and the selected models are aggregated and averaged to predict the climate change trend of Shenzhen from 2020 to 2100. The prediction results show that Shenzhen will face more severe threats from rainstorms and floods in the future. Therefore, this paper proposes a resilience strategy for the city to cope with the threat of flood in the future, including constructing a smart water management system and promoting the development of a sponge city. Moreover, to a certain extent, it is necessary to realize risk transfer by promoting a flood insurance system.

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Learning and Action Alliance framework to facilitate stakeholder collaboration and social learning in urban flood risk management

Environmental Science & Policy ◽

10.1016/j.envsci.2017.10.013 ◽

2018 ◽

Vol 80 ◽

pp. 1-8 ◽

Cited By ~ 24

Author(s):

E.C. O’Donnell ◽

J.E. Lamond ◽

C.R. Thorne

Keyword(s):

Risk Management ◽

Social Learning ◽

Flood Risk ◽

Flood Risk Management ◽

Urban Flood ◽

Stakeholder Collaboration ◽

Urban Flood Risk

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Analysis of Flood Risk of Urban Agglomeration Polders Using Multivariate Copula

Water ◽

10.3390/w10101470 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1470 ◽

Cited By ~ 2

Author(s):

Yuqin Gao ◽

Dongdong Wang ◽

Zhenxing Zhang ◽

Zhenzhen Ma ◽

Zichen Guo ◽

...

Keyword(s):

Water Level ◽

River Basin ◽

Flood Risk ◽

Eastern China ◽

Urban Agglomeration ◽

Dependence Structure ◽

Flood Risks ◽

The Impact ◽

Flood Characteristics ◽

Qinhuai River

Urban agglomeration polders (UAPs) are often used to control flooding in eastern China. The impacts of UAPs on individual flood events have been extensively examined, but how flood risks are influenced by UAPs is much less examined. This study aimed to explore a three-dimensional joint distribution of annual flood volume, peak flow and water level to examine UAPs’ impact on flood risks based on hydrological simulations. The dependence between pairwise hydrological characteristics are measured by rank correlation coefficients and graphs. An Archimedean Copula is applied to model the dependence structure. This approach is applied to the Qinhuai River Basin where UAPs are used proactively for flood control. The result shows that the Frank Copula can better represent the dependence structure in the Qinhuai River Basin. UAPs increase risks of individual flood characteristics and integrated risks. UAPs have a relatively greater impact on water level than the other two flood characteristics. It is noted that the impact on flood risk levels off for greater floods.

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