China’s Three Gorges dam operator plans to fill the Three Gorges reservoir to capacity this year despite the risk of more landslides and worsening environmental problems along the Yangtze, the country’s most important river. 

Earlier this month, Cao Guangjing, deputy manager of China Yangtze River Three Gorges Project Development Corporation, announced that the reservoir level will be raised to 175 metres this September. Five more turbines will be added by year-end, one year ahead of schedule, and an additional six units will be added by 2012, for a total capacity of 22,400 MW.

The decision to increase the reservoir level by nearly 20 metres comes despite last year’s warnings from senior government officials that the dam’s operation could lead to environmental catastrophe unless preventative measures were taken.

At its current operating level of 156 metres, the huge weight of the water behind the dam and its frequent fluctuations have triggered a series of life-threatening landslides and tsunami-like waves up to 50 metres high. Huang Xuebin, from the Headquarters for Prevention and Control of Geological Disasters in the Three Gorges Reservoir, estimates that 70,000 people have already had to be evacuated from unstable areas along the reservoir shoreline since 2003 when the dam started generating power. 

Downstream, Hubei province vice governor, Li Chunming, reported that silt-free water discharged from the dam is scouring critical flood control embankments, putting Wuhan, a city of 9 million, at greater risk of an embankment breach and catastrophic flooding.

If the Three Gorges Corporation gets its way and the reservoir is increased to 175 metres (above sea level), the problems can only get worse. 

Experts, including Weng Lida, former head of the Yangtze Water Resources Commission, have publicly warned against raising the reservoir any higher because it will worsen pollution and siltation in the dam’s 600-kilometre reservoir. Dozens of senior engineers and academics have petitioned the authorities not to raise the reservoir beyond 156 metres in order to reduce the damage caused by heavy siltation upstream and to minimize the number of people displaced.    

Operating conflicts can be expected to intensify the higher the reservoir. The Three Gorges Corporation (and its Shanghai-listed subsidiary Yangtze Power Company) want the reservoir kept high in order to maximize power output – the dam’s chief source of revenue. The flood control authorities want the reservoir lowered by as much as 30 metres, well in advance of every flood season. The navigation authorities want the dam operators to make large discharges during low-water periods to prevent ships from becoming grounded, and to flush away silt deposits in the main river channel. Other demands on the reservoir will follow, not least of which is the massive South-North diversion scheme now under construction to take water from the Yangtze to the parched Yellow River.

Even at 156 metres, conflict over the dam’s operation has already surfaced: Last December, the Yangtze Water Resources Commission told state media that the Three Gorges dam was holding back too much water at a time when water was needed downstream to aid stranded ships. At least 40 cargo ships have run aground in the Yangtze’s middle and lower reaches since last October, reportedly because of record-low water levels and unusually heavy siltation in places. The river authority blamed the dam for a 50 percent drop in river flow downstream of Three Gorges, which has aggravated the region’s worst drought in 50 years.   

Without political or regulatory intervention, more conflicts can be expected to emerge over how to manage the Three Gorges reservoir, for what purposes, and to what effect on the Yangtze river more generally. The problem isn’t simply one of choosing an optimum reservoir level though. A more fundamental problem exists: the Three Gorges Corporation is under no legal or financial obligation to assume responsibility for the environmental damage or economic losses caused by its operating decisions. For now at least, there are no effective limits to the amount of damage this ‘world-class’  dam operator can inflict on the Yangtze river valley and its people.