Two earthquakes occurred Feb. 26 about 50 km southwest of the US$260 million 190-MW Song Tranh 2 hydropower project, according to the Earthquake Information and Tsunami Warning Centre at Vietnam’s Institute of Geophysics (IGP).
Song Tranh 2, completed in 2010, is located in Bac Tra My district, Quang Nam province, Vietnam. The epicenters of both events happened in Nam Tra My district, which boarders Bac Tra My district and is also in Quang Nam province. Each earthquake had a focal depth of about 10 km, according to IGP.
The first event occurred at 11:20 am Hanoi Time (GMT+7); its epicenter was located (15.2410 N, 108.0520 E) in Nam Tra My district; and it measured 3.9 magnitude. The second occurred at 1:02 pm with a magnitude of 3.2. and its epicenter was (15.2490 N, 108.0590 E) in Nam Tra My district, according to IGP.
In November 2012, HydroWorld.com reported a failure at Song Tranh 2 could pose a threat to its neighbor. But, according to Nam Tra My District Chairman Ho Quang Buu, no serious damage occurred as a result of the seismic events. Additionally, no damage to the hydropower facility has been immediately reported and no warnings of dam failure have been issued by the Vietnam government.
The facility’s 96-m-high dam impounds more than 730 million cubic meters of water and is among the largest in central Vietnam.
According to a 2015 study published in Earth Sciences, Song Tranh 2 and its surrounding regions suffered from earthquakes in March 2011, it also suffered from a higher magnitude earthquake in October and November, 2012 of magnitude 4.6 and 4.7 respectively.
In the period from August 2013 to May 2014, about 2,000 seismic events were detected [in the area], and 359 of them were localized. Their magnitudes were calculated and the data are being studied by IGP.