** The content of this article is also discussed at length by Green Earth Volunteers founder Yongchen Wang in her article Walking into Hanyuan. Wang’s article gives human and historical perspectives on the recent developments in Hanyuan County - and includes stunning photographs of the area. Taken together, the article below and Wang’s account tell the following story:
In 2001 plans to build Pubugou Hydropower Station in Hanyuan County, Sichuan were released as part of China’s 10th Five Year Plan. Because the dam’s reservoir would flood many residential areas, migrants were moved to other towns, including Wangong and the new county seat of Luobogang. Luobogang’s construction incorporated many protections against the earthquakes and landslides threatened by the area’s steep topography and unstable geology.
Hydropower Station Sends Migrants to Unsafe Towns
August 11, 2010
[Source: Southern Weekend]
On July 27, a landslide hit Wangong Township, a new settlement in Hanyuan County, Sichuan Province, killing 20 people. (photo by Ran Jin, Southern Weekly)
After the tragic mudslide that struck Zhouqu of Gansu Province, residents of Wangong Township became very worried because they are also situated in an area threatened by landslides. They worried that Hanyuan might become the next Zhouqu!
According to an investigation by Southern Weekly, one year ago, when construction on the town had barely begun, villagers appealed to the government with safety concerns and tried to prevent the building of houses. They failed, however, both to change the location of the town and to obstruct its construction.
Hanyuan, whose geology is as complex and fragile as that of Zhouqu, Gansu, has seen the development of a large hydroelectric plant that will certainly impact the thousand-year-old living ecology of the area. After their relocation, town residents were left in a hazardous situation from which there is no easy retreat.
An Insecure County Seat
Luobogang, the new county seat of Hanyuan, has been under extensive construction since 2008. High slopes, retaining walls, and piles are ubiquitous in the county town. All buildings extend from the slope in a stair-like formation. Surrounded by retaining walls, the piles of these buildings were dug several dozen meters into the ground into stable layers of bedrock. Locals said jokingly that they were “dressing houses in skirts.” This all resulted from the complex geological structure of Luobogang.
Luobogang consists of three rock strata: cracked limestone, severely weathered shale, and schist with loess interlayer (also called “ancient landslide mass”). Moreover, there are faults between each of the three rock strata, which are thicker in some places than in others and do not make up a stable foundation. In addition, Luobogang has a huge coal deposit and mining area. The entire geological structure is extremely complex and unstable.
Nevertheless, this place is the new county seat of Hanyuan where 30,000 people are expected to live.
The issue dates back to 2001, when Pubugou Hydropower Station was included in the 10th Five-Year Plan of China as a hub of hydropower development in Dadu River basin.
Sections of Hanyuan County below 850 meters of altitude were all submerged, and nearly 100,000 people had to be relocated. Among them, 30,000 were able to move out of the county, while the rest will be resettled within Hanyuan.
Li Zhifu and nearly 100,000 other Hanyuan residents were forced to relocate, leaving behind their former rural life-styles and all they had known.
Policy makers selected Luobogang as the new county seat of Hanyuan. However, due to Hanyuan’s unstable geology and steep topography, these changes have put the area at great risk for landslides, cave-ins and other geological disasters. Buildings here have a limited capacity to support the development and major influx of migrants to this area. Thus, geological safety hazards have emerged or been discovered during the construction of many settlements in Hanyuan, including Luobogang and Wangong.
Aware of Danger, Yet Heading Towards it
Among several similar development projects in Hanyuan County, Luobogang is a typical example of rushed construction and its dubious results.
The new county seat was chosen in 2003, but because the hydroelectric plant was built so hurriedly, the relocation of migrants was not preceded by adequate environmental evaluation and geological surveys. And this resulted in the development of geological hazards. “The topography and geological condition are very complex. Ground leveling took between three and five months,” said Zhang Qiao, head of Hanyuan County.
Pressing safety hazards deeply concerned a Hanyuan-based member of National People's Congress (NPC), who continuously reported the problem to the central government and eventually received an official response. Three scholars from the Chinese Academy of Engineering (CAE), as well as several dozen experts went to Luobogang to conduct an investigation. As it turned out, considerable problems characterized the previous geological survey for siting and planning. The investigation found another nine landslide masses which required further control. Forty-five construction projects, buildings with an area totaling 1,490 thousand square meters and the planned resettlement area for 19 thousand residents need to be redesigned.
It cost 36 million Yuan to control just one landslide mass named Luanshigang.
Despite these measures, the outlook for Luobogang’s geological safety is still not promising.
A local official expressed the greatest concern about the underground pipe network. Their hasty and improper installation has left the town’s water at some risk of contamination.
The weak geological structure of Luobogang is most vulnerable to flooding. And underground water seepage can easily trigger landslides or mudslides. Houses have been protected by stakes, retaining walls and piles. However, because the whole housing complex is situated on a steep slope, houses cannot withstand the force of a landslide, particularly because its force increases as the landslide descends the hill, creating a domino effect.
Yet, to ensure the regular generation of electricity, the new county seat had to forge ahead with construction using the existing plan.
On November 1 2009, Pubugou Hydropower station finally closed its floodgate and started storing water.
Still, three quarters of the town had already been flooded before the dikes were built. Geological expert Fan Xiao identified this sometimes-submerged zone as a source of critical danger. The changing water level here undermines geological stability and may cause large-scale landslides. What’s worse, the soft soil of Luobogang, coupled with the downward pull of water flowing downhill, may cause large-scale landslides to strike the entire slope.
In fact, Luobogang has showed some signs of landslides. Nine out of eighteen piles behind Building No.8 at the top of Luobogang had to be reconstructed after the pressure of the massif above snapped them in half this July. Recent buildings and several still under construction have also been plagued by cave-ins and gradual tilting of the land beneath them.
Despite strengthened supervision and control, these phenomena could hardly keep worry and fear off the mind of tens of thousands of Hanyuan residents who moved to the new county site.
During the night of August 4, a rainstorm suddenly hit the new county seat of Hanyuan. Fearing debris flows, many families kept their lights on till daybreak.
At a Loss
Besides Wangong and Luobogang, some other settlements in Hanyuan also have geological problems to various degrees. Two new houses in Yinzheng Village of Guixian Township, built shortly after an earthquake, both suffered from apparent sinking after the reservoir began to store water. Downward shifting and sinking of structures has also affected Jirong Township.
According to Fan, the geological structure of Hanyuan is fragile, and this limits the bearing capacity of buildings. Therefore, the danger of potential geological disasters continues to threaten many areas. From this perspective, it seems inevitable that Hanyuan will suffer more geological disasters such as landslides and debris flows. “One thing we are not sure of is when and where,” he said, adding that Wangong would not be the last place plagued by such disasters.
Wangong Township now poses a tough question for Hanyuan County. “Whether to desert or continue using it,” said county head Zhang Qiao, “should depend on the further research and professional planning.”
Translated by: Tong Jun
Proofread by: Larry Adams
Edited by: Madelyn Finucane