Practical Management of Debris-flow-prone Torrents in Taiwan

Hsiao-Yuan Yin, Chen-Yang Lee, Chyan-Deng Jan and Meei-Ling Lin

In Taiwan, owing to steep topography, weak geological structure, frequent earthquakes and severe rainfalls, especially brought by typhoons, debris flow has become one of the most serious disasters causing enormous losses of lives and properties. The Soil and Water Conservation Bureau (SWCB), Council of Agriculture is the national-level department for the preparedness on the reductions of debris flow disasters. To deal with debris flow hazards, the first step for mitigation works is to identify the locations of debris-flow-prone torrents (i.e., potential debris flow torrents). So far, there are 1,673 potential debris flow torrents in Taiwan, and about 48-thousand people living in the debris-flow endangered flooding areas. In this paper, we will introduce the practical management measures of debris flow hazards including the identification and evaluation of potential debris flow torrents, administrative operation process, watershed investigation, risk potential assessment, flooding zone mapping and evacuation route map. Good preparedness and management of potential debris flow torrents have been proved to be an effective measure in reducing debris flow hazards.

2016/1 186-193