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Ebbs and Flows of Dams
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Zhang Guangdou still remembers the time he spent more than 70 years ago in Tongguan in Northwest China's Shaanxi Province.  

A sophomore majoring in civil engineering at the Shanghai Jiaotong University, Zhang was working as an intern, doing survey work for a railway project.

 

He and other engineers lived on top of a hill by the Yellow River, but they had to trek down the mountainside to wash their faces and fetch drinking water. "The water was very sandy," Zhang recalled in his memoirs, called "The Road I've Traveled in My Life."

 

In 1934, when he won a State scholarship to go and study at Harvard University, Zhang chose to major in hydraulics. He especially focused on hydraulics as a branch of engineering, which consists of the practical application of the mechanics of fluids to the control and management of water with reference to the wants of humans, including canals, waterworks and hydraulic machines.

 

At 92, Zhang has won renown as one of China's top hydraulic engineers, and has participated in the technical and engineering design of all of the country's major hydraulic and water management projects.

 

He has left footprints in mountains ranging from the Guanting Reservoir in Beijing to the Gezhou and Three Gorges dams in central China's Hubei Province, and from Sanmenxia in central China's Henan Province to Xiaowan in the nation's southwestern Yunnan Province.

 

He was awarded 1 million yuan (US$120,900) in June for his life-long contribution to the construction of waterworks and advancement in hydraulics.

 

'Benefit the people'

 

"I chose hydraulics because I believed that area of study would benefit the people the most," Zhang said.

 

Throughout its history, China has been plagued with killer floods and droughts.

 

Because water resources are unevenly distributed both seasonally and geographically, the country frequently suffers from catastrophic floods and droughts.

 

As a result, how to control the disasters has always been a pressing concern. The answer or lack of an answer to the problem had a huge impact not only on the rise and fall of regimes, but also dynasties.

 

After New China was founded in 1949, Zhang and other experts, with strong support from the government, took up the same challenge to try to rein in floods and increase irrigation for farming.

 

Before 1949, there were only 22 large dams with heights over 15 meters, a total installed capacity of 163,000 kilowatts, an annual power production of 710 million kilowatt-hours, and an irrigation area of 16 million hectares.

 

About half a century later, the country is able to manage its annual flooding, Zhang says with pride. Some 400 million people no longer live under the constant threat of disaster.

 

By the end of 1999, the installed capacity for hydropower had increased by 447 fold, making up 24.4 percent of the country's total installed power capacity. Power generated by the hydroelectric industry had grown nearly 300 times.

 

As a result, some 300 million people living in rural areas are able to have full access to power.

 

Also, the annual water supply increased by 5.8 times between 1949 and 2000, with an additional 210 million people receiving a steady supply of drinking water.

 

The irrigation area of farmland more than tripled to 53 million hectares in 2000, of which 33 million hectares is high-yield land.

 

With such increases, China has developed from an agricultural country with little industry into a fast developing economy which ranks sixth in the world.

 

While famine was a chronic problem sometimes impacting on hundreds of millions of people in the past, most Chinese have now been able to have enough food.

 

All this has been achieved, in part, by the construction of over 86,000 dams across the country, the dykes stretching some 260,000 kilometers.

 

Sustainable development

 

But the fast development has also actually caused similar problems, as Zhang earlier this year pointed out, as much of China's water is not fit for human consumption, flooding still occurs and there are water shortages.

 

A member of the expert team looking at the country's sustainable development of water resources, which was organized by the Chinese Academy of Engineering, Zhang said the comprehensive research has enabled him to develop some fresh thoughts.

 

In the first decade of New China, people often talked about "rooting out floods."

 

"I believed that by waterworks, that was, by building dykes and reservoirs, we could conquer nature, the floods," he said.

 

During the same time, Zhang and his colleagues also believed that opening all water resources to expand irrigated fields was the only way to increase China's grain production.

 

"In those years, industrial development was still in its very initial stages and the excessive use of water by industries was not a problem," he said.

 

Today, the rigorous development of water resources is still needed, as per capita water holding in the country is only a quarter of the world's average.

 

Over the past decade, the annual water shortage for the country's irrigated areas has increased to more than 30 billion cubic meters.

 

Though China has the most potential for hydropower in the world, its utilization ratio is still very low - only 12 percent of its potential has been exploited.

 

At the 20th Congress of the International Commission on Large Dams, held in Beijing in September 2000, Premier Wen Jiabao, who was then the vice-premier, said: "The Chinese Government will continue to give priority to the development of water recourses in the course of national economic development... to constantly raise the level of development and dam construction."

 

Zhang said over the years, he and his colleagues have learned bitter lessons from building dams and undertaking water management projects.

 

"I now realize that it's just impractical to think of rooting out floods," he said.

 

"We must learn to live with them and learn to co-ordinate our lives with them.

 

"There will also be a natural limit to the development of irrigated farm fields. The frugal use of water should be encouraged both for farming and industry."

 

For Zhang, ecology and environmental protection is now a major issue when constructing new waterworks and in the country's overall water management.

 

Last month, Zhang hit the headlines as he proposed that the Sanmenxia Dam and its hydropower facilities should be abandoned because its environmental, ecological and social impacts were not taken into consideration during its initial design and construction more than 40 years ago.

 

Completed in 1960, the Sanmenxia Dam was once the largest dam in the country and the only dam appearing on a Chinese banknote.

 

Serious land erosion has plagued the Yellow River, in central China's Henan Province, around the poorly-designed Sanmenxia Reservoir. Sanmenxia, the country's first reservoir, 300 meters in height, lost 40 percent of its storage capacity in 1966, only six years after its completion. Early in the autumn of this year, the common flooding up stream of the reservoir led to a disaster in Shaanxi Province as it had lost ability to soften the blow of flooding.

 

Debate still continues about the fate of the dam.

 

(China Daily December 20, 2003)

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