The Water Supplies Department today outlined the new methods it is using to replace the submarine water mains that run between Sunshine Island, Hei Ling Chau and Peng Chau.
The mains have been in operation for about 50 years and replacing them is necessary to improve water supply reliability.
During a press briefing this morning, the department’s Chief Engineer Michael Leung explained that the “horizontal directional drilling method” is being used to construct more than 2,500 square metres of underground pipework.
He noted that the technique reduces the impact on marine ecology and traffic.
Horizontal directional drilling is a steerable trenchless way of installing underground pipes in a shallow arc along a predetermined path using highly specialised boring equipment, which minimises the environmental impact on the surrounding area.
The $410 million project was launched in September 2013. The pipe that runs from Sunshine Island to Hei Ling Chau was completed in January this year, while the Peng Chau to Sunshine Island section is expected to be finished in the first quarter of 2016.