Sichuan Quake Compromises Dam Intregity
As the rescue and recovery continues in Sichuan, and as the death toll climbs to 29,000, concerns are turning to the region’s rivers. Landslides are creating natural dams on at least 13 of the province’s rivers, backing up water and creating concern that the unstable structures will break and send deluges of water into aid camps and rescue zones. Heavy rains have pounded Sichuan last night, adding to the fear that these new lakes will overflow, leveling the rubble dams in the process. On Saturday afternoon, reports that a wall of water was about to roar down the Qingzhu River prompted rescuers and victims to abandon efforts and stampede down the valley and up onto high ground. This, unfortunately, in a time rescuers are calling critical for finding buried, but alive, victims before it’s too late.
The country’s man-made dams are also in danger of failing after being severely weakened by the quake. The Zipingpu Hydropower Plant on the Minjiang River became a cause of immediate concern when the Sichuan government reported that cracks had developed on the surface of the dam, some walls of the power plant had collapsed and several buildings had partially sunk. 2,000 military troops were rushed to Zipingpu to quickly repair the dam that sits upstream of Dujiangyan, a city rocked by the quake. The dam, which went into operation in 2006, is built on the well-recognized Longmen Shan fault.
Soon after reports surfaced highlighting the danger caused by the weakened dam, a manager at the Zipingpu Development Company, the company that built the dam, quickly responded by saying, “After the earthquake happened in Wenchuan, Sichuan, there were rumors saying there were cracks in the dam.” He continues, “But after the quake, experts from the Ministry of Water Resources made a thorough examination of the important parts of the dam and made a scientific assessment, and they ruled that the dam is structurally stable and safe.”
During our recent expedition to Western China, our team of geologists noticed that other dam construction projects were dangerously close to faults or in areas of rock too unstable to contain the massive amount of water held back by such structures. In January, the government released the results of a study showing 37,000 of the country’s 87,000 dams were dangerously unstable and in urgent need of repair. It is reported that the recent earthquake has affected 391 total dams throughout China.
We also noticed discrepancies between government reports, Chinese domestic media reports and what we witnessed. Discrepancies between reports discussing the extent of the damage to the dam and the reports that a large number of troops was dispatched to the dam call into question China’s motives for censorship of such information.
In this crazy time, let’s just hope that all of our friends in Sichuan are safe.