Wang Shouyong, a former engineer in the Guangdong Provincial Water Resources Department, was one of more than 10,000 construction workers on the Dongjiang-Shenzhen Water Supply Project, which has been hailed as the lifeblood of Hong Kong.

By the end of last year, the project had supplied Hong Kong with 26.6 billion cubic meters of water, more than 1,900 times the volume of West Lake in Hangzhou, Zhejiang province.

Wang, 86, remembers the beginning of the project's construction in February 1964. Two months later, a Hong Kong team visited the construction sites and saw the difficulties the workers were dealing with.

They found it hard to believe such a huge project could be completed in a year, with one exclaiming, "May God bless us!"

An engineering technician quickly replied: "Our God is the people, and the people can create everything. Wait for the good news!"

"We could not bear the painful suffering of water famine for our Hong Kong compatriots, so we worked overtime to forge the project," Wang said. "Our country was very poor then, but we undertook the design, construction and equipment production for the project. As the construction was mainly manual work, more than 20,000 workers were devoted to building the project at the peak time."

The 83-kilometer project was completed in just 11 months and began operations on March 1, 1965.

The project originated in May 1963, when Hong Kong was hit by its worst drought since 1884, with residents only supplied with fresh water once every four days.

Concerned about the plight of Hong Kong's residents and responding to the desperate pleas for help from its British colonial government, Guangdong, which was experiencing the same drought, opened the Shenzhen reservoir, which was about to bottom out, to supply water to Hong Kong as a top priority.

The central government immediately took the initiative to build a water-transporting project to provide a long-term solution to Hong Kong's fresh water supply problem.

Water supplied from the Dongjiang River relieved Hong Kong of its water shortage, and its economy began to soar.

The economic takeoff led to a substantial increase in water consumption, and Hong Kong repeatedly asked for supplies to be increased.

The Dongjiang-Shenzhen Water Supply Project, which also supplies water to the Guangdong cities of Shenzhen and Dongguan, was expanded in three phases from 1974 to 1994, with its annual water supply capacity reaching 1.74 billion cubic meters in 1994, up from 68 million in 1965.

To supply cleaner water, Guangdong invested 4.7 billion yuan ($567 million at the time) to upgrade the project in 2000. After three years of innovative construction, its annual capacity was raised to 2.42 billion cubic meters. It now provides 1.1 billion cubic meters of water to Hong Kong each year that exceeds the national Level 2 standard.

"It can meet the water supply needs of Hong Kong's development for 30 years," said Zheng Hangwei, head of Guangdong Yue Gang Water Supply.

Guangdong's government has rolled out 13 regulations and guidelines since 1991 to protect the water quality of the project, with polluting industrial projects prohibited near its reservoirs.

A water quality monitoring mechanism has been implemented.

"The mode combines 24-hour online monitoring, on-site testing and laboratory testing, which can fully guard the clean water supply for Hong Kong day and night," Zheng said.

Hong Kong resident Denise Lung said: "Thanks to the project, the water supply has been greatly improved in Hong Kong. We've had abundant water for personal hygiene since the 1990s, which was unimaginable in the past.

"Without the project, the livelihood in Hong Kong would be a totally different story."