Builders have completed the final stages of blocking incoming Yangtze River water so they can move ahead with the main structure of the Qingcaosha Reservoir - a key step in Shanghai's plans to provide clean drinking water for its residents.

The reservoir, which will be Shanghai's biggest, is one of the city's largest government-supported infrastructure projects that are aimed at improving the local environment.

The project, which began in late 2007, is scheduled to be completed before the end of this year.

Qingcaosha Construction Co said 30 engineering vessels began dumping stones encased in steel frames into the water outside the dike last Wednesday.

By early Saturday morning, the stones were high enough to block water flowing toward the concrete dike.

This means a breakthrough in the project, as parts of the main structure of the reservoir's circular dike will finally be connected, said Zhou Daohong, an official at Shanghai Chengtou Corp, Qingcaosha's parent. More than 60,000 cubic meters of stones were used, Zhou said.

The reservoir will draw water from the Yangtze River. After processing, the water is expected to pass the country's standards for drinking, government officials said.

The project will cover nearly 70 square kilometers at the mouth of the Yangtze River and cost nearly 16.9 billion yuan (US$2.5 billion).

It is expected to supply 7.19 million cubic meters of tap water each day, enough for about 10 million people.

(Shanghai Daily January 6, 2009)