High Island Reservoir – East Dam 《IV》

High Island Reservoir – East Dam faces the South China Sea, measuring 1,593 feet long and 348 feet high; the West Dam faces Port Shelter and Rocky Harbour, measuring 2,470 feet long and 333 feet high, making the construction extremely complex. To combat erosion from open sea waves, both the East and West main dams were built using a main-and-subsidiary dam system. The main dam impounds freshwater, while the subsidiary dam (breakwater) resists wave erosion, with a buffer zone separating the main and subsidiary dams. The East Dam is famous for the huge and complex concrete breakwater on its subsidiary dam. The East Dam breakwater is composed of over 2,500 dolosse (double-T shaped concrete blocks), each weighing 25 tonnes, directly facing the open sea. The original site of 【High Island Reservoir】 was Kwun Mun (also known as Kwun Mun Channel or Kwun Mun Strait), and like Plover Cove Reservoir, it was built in the sea. The project involved constructing two main dams at both ends of Kwun Mun, connecting the Sai Kung Peninsula with High Island, which was the third-largest island in Hong Kong at the time. These two dams stand up to 64 metres high, alongside three auxiliary dams.