Kelly Haggart, Three Gorges Probe, October 31, 2001
Termites were partly responsible for the collapse of a dam in Sichuan province earlier this month that killed 16 people and left 10 others missing, the Nanfang Dushi Bao (South Urban Daily) reported.
A severe storm that dumped eight centimetres (three inches) of rain in southern Sichuan on the night of Oct 2-3 triggered the disaster. As the level of the Dalugou reservoir rose, the dam was weakened as water poured into passageways that had been dug into it by termites.
The dam, built in the early 1960s out of loosely compacted clay and sandy soil, collapsed shortly after 9 p.m. on Oct. 3, Xinhua news agency reported.
In addition to the probable loss of more than two dozen lives, the onrushing water swept away all or part of 60 houses and killed 1,400 farm animals, the news agency said. Sixty hectares of farmland and nearly one million kilograms of grain were destroyed. Losses were estimated at 23 million yuan (US$2.8 million).
Local experts have concluded that the termites’ tunnelling activity was the main cause of the disaster, while the dam’s soil properties and the heavy rainfall were contributing factors, Nanfang Dushi Bao reported.
The Chongqing Institute for Termites has found termite damage in 99 of 111 reservoirs in Huili county, where the Daluguo reservoir is located, the newspaper said.
Termites are also “a constant threat” to the structural integrity of dams in neighbouring Hubei province, Xinhua reported last year. Fifty-one of 65 dams inspected near the provincial capital, Wuhan, were found to have suffered varying degrees of termite damage.
One of the insects’ nests found in the Xiao’ao reservoir near Wuhan was big enough to hold a small car, China Youth Daily reported.
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