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While costly long-distance water diversion projects can quench the thirst of many seaside cities for the time being, a better long-term solution might lie in the ocean.

Wang Shuguang, director of the State Oceanographic Administration, said recently it is time for the desalination of seawater to move out of the lab and to be developed into an industry.

Almost all of China's most advanced cities are located along its tens of thousands of kilometers of coastline, but most of them are faced with serious water shortages each year.

They have to rely on underground water and long-distance diverted river water for daily subsistence.

Excessive extraction of river water has caused serious environmental problems in some regions. It is also costly and labor-intensive.

To tackle serious shortages caused by a six-year dry spell, Tianjin, the largest coastal city in North China, started channeling water from the Yellow River's Weishan Sluice Gate, 440 kilometers away, last year. It expects to siphon off 350 million cubic meters of water by February.

A similar project will be carried out for Qingdao, a coastal city in East China's Shandong Province, in the near future.

If the desalination of sea water can be better developed, what will mostly be saved is not just money or laboring efforts, but a huge amount of valuable water for China's dry western region, said Wang.

Hui Shaotang, director of the Institute of Sea Water Desalinization and Comprehensive Utilization in Tianjin agreed, saying water diversion only alters the geological location of water and does not increase the amount available.

"The Ministry of Water Resources forecasts that China will use 700 to 800 billion cubic meters of fresh water in 2030, the utmost the country will be able to access in a single year at that time," Hui said.

Luckily, three decades of effort has placed China among only a few countries which are capable of desalinating sea water satisfactorily, according to a report from the institute.

Hui said about half of China's urban water consumption was used for industrial equipment cooling, while about 30 percent of urban consumption was flushed down the toilet - literally.

"With specially constructed pipelines, our treated sea water can do things as well as tap water," he said.

Due to improved technology and production efficiency, the cost to desalinate one cubic meter of seawater has been reduced from 7 yuan (85 US cents) to 5 yuan (60 US cents), making it more marketable than ever.

The sales of drinking water made from the desalination process has been riding the crest of a wave since it was first marketed in Tianjin in October. Selling for just 1 yuan (12 US cents) per bottle, it has obtained a strong foothold in local supermarkets.

"In the initial stage of our industrialization of the new type of water in 1994, our production, costing 10 yuan (US$1.2) per cubic meter, had no advantage at all in comparison with that of average pure water," said Du Chunyuan, one of the developers of the "drinkable sea water."

"But things have changed, effecting profit margins. So we decided to take action."

In less than one decade, the production cost of one cubic meter of desalinized water has decreased.

At the same time, the average production cost for tap water has jumped to nearly 5 yuan (60 US cents).

Du said the utilization of seawater will not proceed if the government does not produce preferential policies, just as it has for reservoir and pipeline construction, Du said.

(China Daily March 24, 2003)