Vietnam's Deputy Prime Minister has ordered the science ministry and related agencies to inspect the dam-induced shakings and underground explosions in the central province of Quang Nam, VnExpress reported Sunday.
The Ministry of Science and Technology and other agencies were asked to report their findings to the government and announce them in the media this month, the newswire quoted the latest order by Deputy Prime Minister Hoang Trung Hai as saying.
Hai made the order two days after scientists from the Vietnam Academy of Science Technology initially concluded that the phenomenon in Bac Tra My District was caused by the operation of the Song Tranh 2 hydropower dam in the vicinity.
Although the scientists said the tremors of between 3-4 magnitude, better known as induced seismicity, would stop gradually when the dam's operations become stable, the district's locals and leaders are still concerned.
The newswire quoted the report of Bac Tra My's People's Committee as saying that since the end of last year when the dam went into operation, about 200 tremors and underground explosions have hit the district.
Last month alone, locals heard four explosions, including the latest on November 27, authorities said, adding that the blasts caused shakings, cracking many houses.
Additionally, "unusual" sinking has occurred on the road from Bac Tra My to Nam Tra My districts, and there were cracks with a depth of more than 2 meters measuring tens of meters in length, according to authorities.
If the tremors last long, ethnic minority people living in the district will move to forests, leading to rampant logging, officials said. Worse still, if the quakes increase to a magnitude of five, many local houses will collapse, they added.
Last Monday, Quang Nam's People's Committee sent letters to the Ministry of Science and Technology and the Vietnam Academy of Science Technology to ask for help in identifying the phenomenon.
The letter suggested related agencies establish gauging stations in Bac Tra My to learn about quakes along with unusual landslides and sinking, as well as to estimate the dam's ability to withstand earthquakes.