Overview and details of the sessions of this conference. Please select a date or room to show only sessions at that day or location. Please select a single session for detailed view (with abstracts and downloads if available).
THU5.2: Integrative flood risk management
management of flood risks at the city of Tabuk
University of Tabuk, Saudi Arabia, Kingdom of
Are private flood mitigation measures successfully contributing to contemporary integrated flood risk management in Germany?
1German Research Centre for Geosciences (GFZ), Potsdam, Germany; 2Institute for Environmental Studies, VU University Amsterdam, The Netherlands
Flood risk is projected to increases in many places due to the effects of climate change and the on-going intensification of human activities in risk-prone areas. These projections and the considerable uncertainties associated with these developments increasingly require integrated approaches in flood risk management in Europe. In addition to traditional flood protection, the latter also aim at reducing the potential consequences of floods, amongst others, by means of flood mitigation measures implemented by private households. In Germany, the responsibility of private households to contribute to damage reduction was increasingly integrated in flood risk management in response to major floods in 1993 and 1995 along the Rhine and in response to the disastrous 2002 Elbe flood. However, even though non-structural measures have become an integral component of contemporary flood risk management, knowledge on them is still limited. This concerns in particular socio-economic and perceptual factors that possibly influence flood mitigation behaviour, the temporal and spatial spread of damage mitigation measures among flood-prone households as well as their effectiveness and cost-efficiency. Insights into these aspects are crucial for determining the efficiency of contemporary flood risk management. In our presentation, we will provide an in-depth overview on these aspects, drawing information from empirical data of computer-aided telephone surveys among 752 flood-prone households along the Rhine. For instance, we find that in addition to flood experience, the social environment and flood-coping appraisals are important factors that influence precautionary behaviour. The obtained insights will be used to provide recommendations to successfully manage the transition to integrated flood risk management concepts.
Analyzing the urban functions to prioritize urban flood resilient actions
1EIVP, France; 2Université Paris Diderot, Sorbonne Paris Cité
The behavior of the civil engineering infrastructures, and their interactions during a flood event, will have consequences on the flood risk level in the built environment. By civil engineering we include on one hand the flood defenses, able to increase the flood risk in case of failures, on the other hand the urban technical networks able to spread the flood risk in cities.
Flood risk management with limited data – case study Han River, China
1Ernst Basler + Partner, Switzerland; 2Swiss Agency for Development and Cooperation, Beijing
Authorities responsible for flood control and protection urgently need an overview on the expected flood risks on their territory. They seek for cost-effective measures to reduce the risks significantly. Generally, risk assessment requires detailed data, often only partially available. A pragmatic approach to risk assessment therefore is an adequate alternative. In an interactive process – during consultations and workshops performed among relevant stakeholders, decision makers and locals – estimates and results for crucial issues are developed. This process is substantially supported by the online IT-tool RiskPlan, which is widely used in Switzerland and abroad. Within a Sino-Swiss partnership including the Ministry of Water Resources China, the Swiss Agency for Development and Cooperation (SDC), the Federal Office for the Environment (FOEN) and Ernst Basler and Partner (EBP), the RiskPlan approach is tested in the Han River catchment, Hubei Province, China. Currently only rough data to hazard and damage potential are available. The risk situation has been analysed in a consultation in Wuhan, using the knowledge and experience of flood expert partners of the Changjiang Water Resources Commission (CWRC). RiskPlan is promoting the risk dialogue among the experts. Based on the local knowledge and available data, four scenarios, their frequency and expected damages have been estimated applying a participative process. The total yearly expected damage for the damage indicators fatality, material damage and agriculture damage have been assessed, monetised and aggregated, expressed in Chinese Yuan (CNY). The generated flood risks in the Han River catchment contributes to the integrated flood risk management. The need for action is identified, a priority setting is enabled. Additionally, RiskPlan allows the economic assessment of flood protection measures regarding cost-benefits. As the impact of extreme weather events grows in China, floods and droughts being among the major factors, integrated flood risk management becomes an urgent necessity.
A preliminary study of flash flood in Hunan Province, China - spatio-temporal characteristics, trends and risk management
Beijing Normal University, China, People's Republic of
Flood risk management has always been a great concern in China and huge resources has been invested on the construction of flood-defending systems. After decade years of continuous efforts, most of the major rivers in China have been effectively regulated and the threat from traditional river flooding has been greatly reduced. While as a result of increasing frequency of extreme rainfall events and high vulnerability of small catchments in mountainous area, flash flood has become more and more severe and been the most lethal type of flood. According to statistics, from 2000 to 2009 annual deaths caused by flash flood accounted for about 80% of total flood-related deaths in China. Hunan Province, located in Central China, is characterized with mountainous areas in the south and southwest parts and intensive precipitation in summer due to the east Asian monsoon and typhoon system. As a result, Hunan is highly exposed and vulnerable to flash flood with hundreds of deaths and millions RMB Yuan of losses every year. It is urgent to fully investigate flash flood risk in Hunan Province and take effective measures to minimize the loss. This study investigates the spatio-temporal variation of flash flood in Hunan Province with the dataset of flash flood events and losses from local bureau of civil affairs to indicate the most vulnerable place and time to flash flood. Then meteorological data associated with flash flood events are analyzed to construct the probability distribution of precipitation triggering the hazard. Statistical methods are used to detect the trend of precipitation in the season of flash flood, and based on the distribution of threshold precipitation the risk of flash flood is assessed. Finally, we discuss alternative risk management strategies of flash flood in Hunan Province, highlighting the importance of non-structural measures.
Chronicling and mapping the physical and social components of the 2009 flood disaster and the disaster risk reduction initiatives of urban poor communities in Metro Manila, Philippines
1Crawford School of Public Policy, RMAP, College of Asia and the Pacific-The Australian National University, Australia; 2Geography Department, University of the Philippines, Quezon City; 3Geography Department, University of the Philippines, Quezon City; 4Geography Department, University of the Philippines, Quezon City; 5Geography Department, University of the Philippines, Quezon City; 6Geography Department, University of the Philippines, Quezon City; 7Geography Department, University of the Philippines, Quezon City
Strengthening resilience to flood risks among urban poor communities can benefit from community mapping of flood risks, social vulnerabilities and grassroots-initiated disaster reduction initiatives. With research funding from Christian Aid and the Manila Observatory, researchers from the University of the Philippines’ Department of Geography had engaged in chronicling the physical-geographical-economic and social causes of flooding in five urban poor settlements and mapped the land use changes on river banks (20 m easement) and the constriction and disappearance of creeks and waterways in Metro Manila, Philippines. The maps of flood depths that were experienced by residents of urban settlements on the river banks illustrated the extent of devastation of the floods that greatly paralyzed population movements and economic activities in the metropolis and adjacent provinces in Luzon. The unplanned conversions of river banks into concrete spaces due to the rapid urbanization of Metro Manila and several towns in adjoining Rizal and Laguna Provinces were directed related to the widespread floods that were brought about by tropical storm Ketsana (Typhoon Ondoy – Philippine local name) in 2009. In-depth interviews among local government officials and men and women in affected urban communities were held to relate their flood experiences, evacuation strategies and disaster risk reduction initiatives from 2009 onwards. The resulting data bases were incorporated into the risk assessment initiatives of the affected urban poor communities to reduce their vulnerabilities to floods. The data bases were shared with the members of the affected communities to provide them with information that they can use to increase their resilience to flood disasters. Inundation events are projected to recur more frequently because of the changing patterns and intensification of extreme weather events in the Philippines due to global atmospheric warming.