The five-level dual-track ship locks of the Three Gorges Dam,
the largest of its kind in the world, passed engineering tests
after 13 years of construction, experts announced on Friday.
"The permanent ship lock demands the most sophisticated
technology in the entire Three Gorges project," said Zhang
Guangdou, an academician on both the Chinese Academy of Sciences
and the Academy of Engineering.
"Tests have shown the lock would ensure safe navigation for
ships when the water level behind the dam rises from 156 to 175
meters. This means the two-way traffic can resume on May 1, two
months ahead of schedule," he said.
"The engineering, metal structures, machinery and electronic
equipment of the lifting facility for the 113-meter drop between
the upstream and downstream have reached international standards,"
said Niu Xinqiang, vice director of the Yangtze River Water
Resources Committee.
The lock, 6.4 km long and costing 6.2 billion yuan (US$775
million), started to be built into mountainous terrain on the
northern bank of the Yangtze in 1994 and has been the only
navigable route past the dam since 2003.
The four-level operation began in 2004. The lock has been
restricted to one-way traffic, alternating every 24 hours, since
September last year when work began to raise the beds of the two
uppermost tiers of the lock from 131 to 139 meters.
The operation began on the southern route, which reopened on
January 20, and work on the northern track started the same day.
The Three Gorges Project is located on the middle reaches of the
Yangtze River, China's longest and one of the country's most
important inland waterways.
(Xinhua News Agency April 28, 2007)