The rapid changes due to development process and ever increasing expansion of human settlements bring about unexpected risks to urban communities. Concentration of wealth in major urban centers poses huge economic risks in the event of a catastrophic disaster resulting from events that exceed the design standards. The project examines the optimal means to "prepare for the unforeseen" extremes brought about by environmental change. Risk assessment for hazards brought about by extreme events is carried out with dynamic spatial information to arrive at realistic scenarios in order to mitigate adverse impacts and reduce loss of lives and properties. This project seeks to implement risk assessment from catastrophic events resulting from extreme rainfalls. Three sub programs are proposed as, (1) Assessment of catastrophic flood risk resulting from overflow or breach of major rivers in urban centers in Asia Pacific region 2) Vulnerability of underground space to combined hazards and (3) Landslide risk.

Flood Risk Assessment

Case studies on risk assessment related to a possible 'Catastrophic Flood' are conducted under this program. Current study areas include Hanoi and Bangkok. Studies in China, Sri Lanka, Nepal and the Philippines are proposed.

Urban Floods

Urban floods under extreme natural conditions are investigated under this program. Underground flooding in urban systems (Fukuoka) and Tsunami flooding in Sri Lanka are two of the case studies completed recently. The program also focuses on risk analysis, development of loss functions and transfer of methodologies related to flood risk assessment across countries.

Landslide Risk Management

Landslide loss mitigation is carried out by strengthening vulnerable slopes by protective infrastructure, anchoring, drainage and landuse control. Often Landslide zonation is carried out to guide appropriate mitigation measures based on geology and other physical characteristics. On the other hand, heavy casualties are often the result of catastrophic events triggered by extreme rainfall. Experience shows that intense precipitation can cause devastating landslides even in moderate or relatively low landslide risk areas. Therefore landslide warning emerges as one of the most effective means in preventing loss of life, making it an extremely important research area. Landslide warning calls for an inter-disciplinary approach encompassing hydrology, geology and climatology. Coupling subsurface saturation and ground water movement with dynamic updates of soil strength decreases has been an active research field for quite some time. Success to certain degree has been reported and various levels of conceptual, approximate and empirical methods are being developed to enable real-time forecasts. It is clear that the way forward in these studies lie in understanding and predicting in real time, saturation and corresponding loss of strength of soil that bring out the mass movement. Recent advances in hydrological modeling have made it possible to forecast moisture build up and subsurface water movement with improving reasonable. With further enhancements in capabilities to map and monitor physical characteristics of the terrain such as elevation and land cover together with refinements to geological and soil databases, these forecasts would become more and more accurate in the future. Such developments are especially important in the developing countries where ground based data are sparse. Therefore it is necessary to launch programs for research and training where developing countries can take advantage of emerging new technologies and develop methodologies to address this issue.

UNU is currently developing a research project with partners in Bhutan, Nepal and Sri Lanka for landslide risk management. Please see the project outline here

The objectives of the project is to develop a system for landslide risk management in Bhutan, Nepal and Sri Lanka. The system consist of 3 major components;

• Landslide forecasting system

• Real-time Risk Communication System

• Landslide risk management component

The outline of the proposed system is given here.

Country Backgrounds: Bhutan

• GIS system

  • Data Sources

    1. Cities: ArcWorld; ESRI Data& Maps 2006

    2. Capital City: ArcWorld; ESRI Data& Maps 2006

    3. Rain Stations: Converted from geological coordination table using ArcGIS Desktop (UNU) 2007 　New

    4. Streams: Global Drainage Basin Database (GDBD); Center for Global Environmental Research at the National Institute for Environmental Studies; Yuji Masutomi, Inui Yusuke, Kiyoshi Takahashi, and Yuzuru Matsuoka (2007) Development of highly accurate global polygonal drainage basin data. Accepted to Hydrological Processes.

    5. Basins: Global Drainage Basin Database (GDBD); Center for Global Environmental Research at the National Institute for Environmental Studies; Yuji Masutomi, Inui Yusuke, Kiyoshi Takahashi, and Yuzuru Matsuoka (2007) Development of highly accurate global polygonal drainage basin data. Accepted to Hydrological Processes.

    6. Country Boundaries: ArcWorld; ESRI Data& Maps 2006

    7. Province Boundaries: ArcWorld Supplement; ESRI Data& Maps 2006

    8. StateProvinceNames: ArcWorld Supplement; ESRI Data& Maps 2006

    9. Water body: ArcWorld; ESRI Data& Maps 2006

    10. Satellite Image: Global Imagery; Earth Satellite corporation, 150 m pixel resolution.

    11. Landuse: UMD Land Cover Classification (University of Maryland; Department of Geography); 1 km pixel resolutions; Product Coverage Date: February 2000, Publish: 1998.

    12. Elevation: Global Digital Elevation Model (Shuttle Radar Topography Mission; SRTM); SRTM: NASA, NGA, USGS, EROS, ESRI; 90 m pixel resolutions; Product Coverage Date: February 2000.

    13. Hillshade: Derived from Elevation data using ArcGIS Desktop 9.2 with Spatial Analyst.

• Rainfall forecasts

• Landslide History