"The channel adjustment is just part of the city's overall planning, according to which the center area of the city is supposed to focus on the tertiary industry and tourism," Shang said. Following the urban planning blueprint, factories began to move out of town and large and medium-sized coal and steel plants were relocated in the suburbs by the side of the Beijing-Hangzhou Grand Canal.

Two large wholesale markets for agricultural products in the southern part of the city were also ordered to move out of town, said Shang. In 1991 the Shangtang River, one of the city's oldest navigable channels, reached a cargo volume of 4.9 million tons. "Nowadays there are no ships at all on the river except for a few tourist boats," he said.

"As cargo distribution centers were relocated out of the city, some of the channels within the city lost their transportation value. So, it is time for them to retire."

Water transportation capacity will not be affected with the retirement of these 18 small channels, according to He. "Though they make up two thirds of the city's overall channels, they account for just one third of the total length of the navigation routes," he said.

The majority of the 18 retired channels are small ones, whose shipping capacity is very low and cannot satisfy the needs of large-scale cargo transportation, he added.

These small channels cannot be widened or upgraded due to bridges and riverside architecture so the city has resorted to using larger channels outside the city center.

"As early as 1988, the city changed the location of an 8-km course of the Grand Canal from the inner city to the suburbs. It achieved an enormous economic benefit at a small cost and guaranteed a current capacity of passing ships in the 500-ton class," He said.

In 2006, the city worked out a plan to integrate and build a network of main water channels, featuring high-class navigation channels that cater to the trend for large-scale shipping. Statistics show that the Suzhou part of the Grand Canal has achieved a cargo volume of 22 million tons of coal and 4.6 million tons of building materials in 2007.

Environmental concerns

"I think it's a good move to let the channels retire from cargo transportation. Now I don't have to keep the windows of my house closed all the time to stay away from noise any more," said Suzhou native Zhu Kun. He has lived by the side of Shantang River for 50 years.

The retirement of the 18 channels will improve the urban environment, in terms of noise reduction and water quality, said Shang Qingcong. Tests have showed that cargo ships can produce noise that exceeds 100 decibels and spreads as far as several kilometers. The noise was a