Abstract
Without any omen, massive landslides induced by the Chi-Chi earthquake blocked up gorges of Ching-Shui creek, and produced a new landslide lake. Although emergency spillways have been constructed to prevent dam failures, overtopping and possible breaching may still occur due to excessive inflows in raining seasons. As a result, the downstream valleys will have serious inundation and the safety of people and properties will be in immediate danger. The purpose of this work is to simulate and to analyze the inundation potentials downstream of Tsao-Ling landslide lake using a hydrologic/hydraulic approach and GIS (Geographic Information System) technology. Hydrologic analysis is employed to describe regional rainfall-runoff characteristics and to design rainfall/runoff scenarios. One-dimensional dam break flood routings are performed with different return periods of rainfall events and dam failure durations for downstream creeks. The depletion hydrographs of dam break routings are applied into two-dimensional overland flow simulations for downstream lowlands. The results of hydraulic computations are evaluated with GIS maps for inundation potentials analysis, which can be used to assist the planning of emergency response measures.
Original language | English |
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Pages (from-to) | 289-303 |
Number of pages | 15 |
Journal | Natural Hazards |
Volume | 25 |
Issue number | 3 |
DOIs | |
State | Published - 2002 |
Keywords
- Dam break flood routing
- Hydrologic analysis
- Inundation potentials analysis
- Landslide lake
- Overland flow routing