Overtopping failure of a large-scale artificial dam in Taiwan (Feng and Chen, 2012) - Part 2 Surge

The height of the man-made test dam is 4 meters. The dam was built in the Huisun experimental forest of National Chung Hsing University (NCHU), Taiwan. The water overflowed the dam at 8 min 25 sec (08:25) of this video. The video was recorded by Prof. Zheng-yi Feng of NCHU on April 10, 2012 around 9:30 am. Prof. Su-chin Chen of NCHU established the dam for a group research on landslide dam failure mechanism supported by Taiwan National Science Council. The copyright of the video file is owned by Prof. Zheng-yi Feng and Prof. Su-chin Chen of NCHU, Taiwan.

Observation of this dam failure:
1. Due to the shooting angle from the downstream and steep sloping of the creek bed, we cannot see the water rising during impounding at the upstream side.
2. The inflow from an upstream canal was about 1~2 CMS.
3. Water is seeping out from the bottom of the dam since 00:10.
4. The seepage water gradually increases with increasing water level.
5. At 08:25, start of overflow.
6. A small "alluvial fan" was formed till 10:35 by the eroded dam materials.
7. The dam breached at about 10:45 and the surge wave front traveled downstream.
8. There is a peak flooding discharge/stage can be observed.
9. The dam was eroded horizontally and lowered gradually.
10. The flash flood due to the breach lasted about 1 min 15 sec.
11. and others.

By Prof. Zheng-yi Feng on May 12, 2012, e-mail: [email protected]