Yunnan authorities said on Monday that the earthquake that struck the border of Sichuan and Yunnan provinces, killing four and injuring 150, was not related to the ongoing construction of hydroelectric plants along the Jinsha River.

Zhang Junwei, director of the science and technology department of the Yunnan Provincial Seismological  Bureau, denied the 5.7-magnitude earthquake, which saw 22,000 people evacuated, was caused by the plant construction.

“The nearest plant is about 100 kilometers away from the disaster area. Given this distance, the plant would not be capable of having a direct impact on the geographic condition of that area,” Zhang said.

He further explained that earthquakes caused by dams and hydroelectric plants usually happen very close to those sites and constitute a different sort of earthquake than the recent one, which was blamed on tectonic plate movements.

A geologist agreed with the Yunnan authorities, dismissing on Sunday the blame being put on the plant’s construction, though he warned of potential future disasters when the plants come online.

“Hydroelectric plants can lead to serious earthquakes only when they are completed and the dams start to fill up with water. However, the plants near the epicenter are still under construction now,” Fan Xiao, a geologist with the Sichuan Bureau of Geological Exploration and Exploration of Mineral Resources, told the Global Times.

“As the dams begin to fill with water in the next decade, there will be a high possibility of earthquakes happening. The water in the dam will press down on the rocks below, potentially causing a slip among the fault line, which could lead to an earthquake. The water can also infiltrate the rock bed, which may also set off a quake,” Fan said.

Zhang also said that Yunnan is a province frequently afflicted by earthquakes because the area straddles two tectonic plates.

In 1998, another 6.2-magnitude earthquake rattled the area, killing six and injuring another 1,974 in both Yunnan and Sichuan provinces, causing economic losses of 486 million yuan ($76.38 million).

According to a report by the Shanghai-based Xinmin Evening News, there are a total of 25 hydroelectric plants being constructed or planned along the Jinsha River. When all are operational, the plants will have a total capacity four times that of the Three Gorges Dam.

Apart from the Jin’anqiao plant, which started running back in 2010, all the other plants are yet to be finished.

By Chen Xiaoru in Shanghai