Beneath the surface of this seemingly ordinary reservoir lies a story of survival and political maneuvering. The story of the Dongkeng Reservoir begins in a post-war Hong Kong. Rapid population growth strained the water supply. The colonial government sought a new source. They turned to the mainland and the Shenzhen Reservoir.
In 1959, Guangdong authorities invited Hong Kong guests to celebrate the new Shum Chun Reservoir, now known as Shenzhen Reservoir. Construction had started immediately after approval to supply water to Hong Kong. The reservoir could supply a city of three million for seven months.
The British Royal Air Force had already surveyed the area. They captured the start of construction. This included river diversion and ground clearance. China was struggling with famine at the time. Water conservation became a priority. The decision was made to construct ten major reservoirs. Shenzhen Reservoir was among them. Zhou Enlai, the Premier, closely followed the project. He helped secure key materials.
The Shenzhen Reservoir aimed to irrigate farmland. It was also intended to generate electricity. Supplying water to Hong Kong was always a desire. The reservoir sits 3.8km north of Hong Kong. It is in hills with a 60.5-hectare catchment area. The dam is made of compacted earth. It spans between two hillsides. The structure is 30m high and almost 1000m long. Its total volume is about 1.8 million m3. A second dam closes out a low col. Both dams used local material.
With a 45.77 million m3 capacity, the reservoir was twice the size of Tai Lam Chung. It was the largest in Hong Kong at the time. A spillway prevents water from overtopping the dam. It ensures the earth dam wouldn’t erode. It also provided a safe route to discharge water. Villages in the valley were relocated for construction.
In 1960, Guangdong officials offered water to Hong Kong. This presented a dilemma for Hong Kong. Governor Black didn’t want to depend on the mainland. The new source addressed the shortage but boosted the Mainland Government’s political standing. The Governor negotiated while developing the Plover Cove Scheme. He hoped to resolve the short-term demand and long-term need.
To mitigate political risks, Hong Kong took steps. They ensured a formal agreement with competitive rates, avoiding the appearance of charity. The agreement was published to prevent one-sided propaganda. Water supply departments signed the agreement. This avoided high-ranking officials’ involvement. The agreement was only for times of need. There was a fixed maximum supply. Any mention of enlarging future supply was removed. The water was supplied to the entire distribution network. No preferred district received preferential treatment.
Construction began with over 10,000 migrant workers using basic tools. To meet the rainy season deadline, the workforce increased to 40,000. They also used 5,000 carts and some tractors. The initial daily quota was 1m3. This increased to 5m3. Some achieved 54m3 in a day. Workers slept in mat sheds. They worked long hours with limited rations.
Zhang Jingai, an 18-year-old girl, was a “flying girl” on site. She was known for her speed. By March 4, 1960, the dam was complete, two months ahead of schedule. It became known as the “100 days dam”. Guests celebrated the completed works on March 5, 1960.
Typhoon Mary in June 1960 brought torrential rain. The storm filled the reservoir overnight. The spillway was not complete. The army stood ready to blow up the temporary dam. The storm eased, and the water levels subsided just in time.
A 3.8km pipeline was needed to reach the Hong Kong boundary. Steel was secured from Beijing. The Waterworks Office built a pumping station. It pumped water through a 1.2m steel main to Tai Lam Reservoir.
The agreement was signed on November 15, 1960. Hong Kong would receive 5,000 million gallons, provided rainfall was sufficient. The rate was HK$0.234 per thousand gallons. The signing occurred at Shum Chun railway station. It was part of a ten-hour celebration.
Tao Zhu, who initiated the reservoir, was later tortured to death during the Cultural Revolution. Cao Ruoming, the commander, was transferred and died early in the Cultural Revolution. The Shenzhen Reservoir secured Hong Kong’s dry season water supply. It also paved the way for future schemes like the East River Scheme.