Chinese dam collapse warns of future disasters

With piles of rubble dotting a painterly Chinese landscape --a gaping, dried-up ditch -- is all that's left of a once-colossal dam in China's Guangxi province.

Last reinforced 25 years ago, the dam was overrun by heavy flooding last month.

It caused immense damage, inundating roads and swallowing up fields.

Its collapse suggested that neglect left this reservoir open to disaster.

But perhaps most concerning of all - is what that might mean for the 94,000 other aging dams across China.

They loom over river basins and flood plains much more densely populated than when they were first built.

81-year-old Luo Qiyuan lives in Shazixi village, near what's left of the dam.

He also helped build it over half a century ago.

"We don't know how it collapsed. The flooding was severe - it was really severe and we have never been this bad before. This time the flooding is really severe. The water went over the dam, then it collapsed. It collapsed because the water level was so high. Then the flooding came towards our village. I have never seen such flooding in my life. It was very severe."

It was built in 1965, made of compacted earth, and designed to help irrigate farms in Shazixi.

It could hold enough water to almost fill 78 Olympic-size swimming pools.

When it collapsed last month, Chinese media didn't pick up the story.

But on a visit to the reservoir in mid-July, Reuters found that the entire length of the dam - some 100 metres -- had largely vanished.

It was unclear if record-breaking rains were to blame for the Shazixi collapse, or if there was a design problem.

The water resources department in the area declined to comment and the county government did not respond to a request for comment.

But China may see some even bigger storms soon.

Floods are part of life in China, and its seen some of the deadliest in history.

But environmental groups say climate change is bringing heavier and more frequent rain.

In Guangxi alone, official data shows both rainfall and temperatures were significantly higher on average over the past 30 years.

And as villager Li Yuanjun suggests, it raises the question of whether China's infrastructure can keep up with its rapidly changing climate.

"Every dam here has 50 years history. Even residential building that's with 50 year-history has some dangers. If you don't reinforce and protect them, they can't stand for long."

Thousands of these dams were built in the 1950s and 1960s in a rush led by Mao Zedong to fend off drought in the agrarian society.

But over half a century later, it's unclear how much longer they'll last.

A Chinese official said in 2006 that dykes had collapsed at over 3,000 reservoirs over the past 50 years--due to sub-standard quality and poor management.

Aware of the risks, authorities say they have been reinforcing and raising old dams, stepping up inspections and planning new ones with increased storage capacity.

But only time will tell if China's dams will hold back disaster -- and protect the livelihoods of millions of people who live downriver.

Video Transcript

- With piles of rubble dotting a painterly Chinese landscape, a gaping dried up ditch is all that's left of a once colossal dam in China's Guangxi province. Last reinforced 25 years ago, the dam was overrun by heavy flooding last month. It caused immense damage, inundating roads and swallowing up fields. Its collapse suggested that neglect left this reservoir open to disaster.

But perhaps most concerning of all is what that might mean for the 94,000 other aging dams across China. They loom over river basins and flood plains much more densely populated than when they were first built. 81-year-old Luo Qiyuan lives in Shazixi Village near what's left of the dam. He also helped build it over half a century ago.

INTERPRETER: We don't know how it collapsed. The flooding was severe. It was really severe. We've never seen it this bad before. The water went over the dam, then it collapsed because the water level was so high. Then the flooding came towards our village. I've never seen flooding like it in my life.

- It was built in 1965, made of compacted earth and designed to help irrigate farms in Shazixi. It could hold enough water to almost fill 78 Olympic-sized swimming pools. When it collapsed last month, Chinese media didn't pick up the story. But on a visit to the reservoir in mid July, Reuters found that the entire length of the dam, some 100 meters, had largely vanished.

It was unclear if record breaking rains were to blame for the Shazixi collapse, or if there was a design problem. The water resources department in the area declined to comment, and the county government did not respond to a request for comment. But China may see some even bigger storms soon.

Floods are part of life in China, and it's seen some of the deadliest in history. But environmental groups say climate change is bringing heavier and more frequent rain. In Guangxi alone, official data shows both rainfall and temperatures were significantly higher on average over the past 30 years. And as villager Li Yuanjun suggests, it raises the question of whether China's infrastructure can keep up with its rapidly changing climate.

INTERPRETER: Every dam here has a 50 year history. Even a residential building with a 50 year history has some dangers. If you don't reinforce and protect them, they can't stand for long.

- Thousands of these dams were built in the 1950s and 1960s in a rush led by Mao Zedong to fend off drought in the agrarian society. But over half a century later, it's unclear how much longer they'll last. A Chinese official said in 2006 that dykes had collapsed at over 3,000 reservoirs over the past 50 years due to substandard quality and poor management.

Aware of the risks, authorities say they have been reinforcing and raising old dams, stepping up inspections, and planning new dams with increased storage capacity. But only time will tell if China's dams will be able to hold back disaster and protect the livelihoods of millions of people who live down river.