Two villages in southwestern Lantau, Shek Pik and Fan Pui, would have to be removed to make way for the new dam. Their people, having no knowledge of modern technology and no need for a dam, viewed the project with fear and hostility. The dam was not, in fact, being built for them; its collected water was to be carried by pipeline to Hong Kong Island, Kowloon and Peng Chau. Fan Pui, the smaller village, had to be treated with diplomacy and compensated before its 62 people consented to move to another rural area on the island. Inhabitants of Shek Pik elected to move to Tsuen Wan, settling in new five-story blocks. The oldest inhabitant, an eighty-six-year-old woman, made the transfer with full official ceremony, her sedan chair borne by four policemen. The ancestral tablets and household gods also made the trip on the shoulder-poles of respectful bearers. Anything less than this diplomatic ritual would have made the entire relocation impossible.
Preliminary work on the Shek Pik Dam became a trail-blazing venture into unexplored territory. A ten-mile paved road had to be built along the edge of the sea from the sheltered harbor at Silver Mine Bay to the future dam site. Test borings at the foot of Shek Pik Valley where the dam was to cross disclosed that the ground was a porous mixture of gravel, boulders, and rotten granite down to 137 feet below the surface. Since the ground stood only 15 feet above sea level, seawater would be able to seep into the reservoir and the fresh water in the reservoir would escape beneath the dam, undermining it.
If a regular concrete dam were to be built on such ground, its foundations would have to go down at least 137 feet, a frightfully expensive procedure. Engineers produced a reasonable alternative by using the recently developed technique called grouting. In this process, a mixture of water, cement, and clay is pumped into porous ground under high pressure, sealing off the foundation without requiring excavation to bed rock. A series of tests established that this process was feasible for Shek Pik, and preparations to build an earth dam were made in 1958.
The dam was to be 2,300 feet long, with a maximum height of 180 feet. It would back up 5 billion, 400 million gallons; a third of the colony’s total water storage. A ten-mile tunnel was to carry the water from the treatment works near the dam to Silver Mine Bay. From there it would be pumped under the sea in twin 30-inch-diameter pipelines to reach Hong Kong Island, eight miles east of Lantau. Fifteen miles of catchwaters were to drain about twelve square miles of land, aided by the fact that rainfall on Lantau Island is generally ten percent heavier than on Hong Kong Island and is more evenly distributed throughout the year.
One of the tunnels was delayed for a time by a peculiarly Chinese problem; its “fung shui” was regarded as injurious to a resident dragon. The fung shui, a very important consideration among local people, meant that any proposed change in the local landscape had to be undertaken with great care. It would never do to nip off the top of a hill that was shaped like a dragon, for that might blind the mythical beast and put a hex on the countryside. The thing to do was to hire a fung shui expert from a nearby village; for a suitable fee, he would propitiate the dragon and the work of dam-building could proceed.
In a more practical way, the engineers had to install concrete channels and pipelines to make certain that sufficient quantities of water were diverted to irrigate farms near the catchment area. Hillsides above the big catchwaters had to be faced with chunam, a mixture of straw, lime, clay and cement which keeps the hillside soil from washing into the catchwaters and clogging them.
By early 1962, the southwestern portion of Lantau was criss-crossed by deep catchwaters and the earth dam was rising at the foot of the valley, with its core of impermeable clay being made ready for a covering of ordinary clay and dirt. Up in the mountains at the head of the valley, Buddhist monks and nuns continued their quiet, contemplative existence in the Po Lin Monastery, almost untouched by the dam project. Even when a few more guests stayed overnight at the Po Lin hostel, the pattern of prayer and work did not change.
Construction of the dam, pipelines, tunnels, and catchwaters became an international venture, with French, English, American, and Hong Kong contractors sharing the work under supervision of government engineers. The entire $40 million job is to be completed late in 1963.
There were no claims that the completion of Shek Pik would give the colony all the water it required. The new dam on Lantau and the water pumped in from China would be helpful, but far short of indicated needs.