The rain-gathering potential of the New Territories had been exploited by the 1930s with the construction of the Shek Li Pui and the Jubilee Reservoirs. When the Japanese arrived, they found 13 reservoirs with a storage capacity of 6 billion gallons. They let the mains deteriorate during their occupation of the colony, applying their own brand of water-rationing by cutting off all supply to entire sections of the colony whenever they chose to. Following World War II, the government tried deep boring to reach underground water resources, but this turned out to be scarcely worth the effort. After years of surveying and study, engineers laid out the Tai Lam Chung Reservoir System, at the central western end of the New Territories. This called for construction of a two-section dam 2,300 feet long and 200 feet high. This gigantic main dam, built entirely of concrete, created a reservoir of 4 billion, 500 million gallons. Twenty-three miles of “catchwaters,” or concrete channels to trap run-off from the rains, funneled the surface water from 11,000 acres into the reservoir. It took eight years to construct, being completed in 1960 at a cost of almost $25 million. None of these large dams served the needs of the hundreds of small villages in the New Territories, which still relied on wells and streams or threw up earth dams in hilly areas to form their own miniature reservoirs. After World War II the colony government and the Kadoorie Agricultural Aid Association, a private philanthropic body, furnished grants of cement to replace these crude and leaky installations with concrete dams and concrete-lined wells, plus pipes to carry the water into the villages. Rice crops in the New Territories were dependent on their own irrigation systems, traditionally constructed of earth channels and dams. They were laid out with evident shrewdness to cover the greatest possible area, but the dams and channels had to be nursed along constantly to prevent leaking and to keep them from becoming choked with weeds. The government and the Kadoorie Association also furnished materials to replace these systems with concrete dams and channels. Nearly 600 dams and more than 220,000 feet of channels have been improved in this way since World War II. When the Tai Lam Chung Reservoir was under construction, a very delicate balance of catchwaters and irrigation channels had to be worked out so that the reservoir collected all the excess summer rain not required for irrigation, but did not draw off the sparse winter rains which farmers had to have. The farmers’ initial assumption when they saw the huge catchwater channels passing the farms on their way to the reservoir was that they were being robbed of water; it took considerable diplomacy and convincing proof to allay their suspicions.