To support Hong Kong's sustainable development, the Government actively explores innovative approaches to develop new land resources. One of the possible approaches is rock cavern development. Cavern construction is an established technology that has seen continual improvement in its application. A number of cavern schemes for various uses have been successfully adopted around the world with notable examples in Canada, China, Finland, Japan, Korea, Norway, Singapore, Sweden and the USA.
In fact, there are successful local examples of accommodating various facilities in rock caverns, including the Stanley Sewage Treatment Works completed in 1995, as well as Island West Refuse Transfer Station and Kau Shat Wan Explosives Depot both completed in 1997. Also, in 2009, the University of Hong Kong reprovisioned the Western Salt Water Service Reservoirs in rock caverns to release the site for its Centennial Campus development. These projects have demonstrated that rock caverns are valuable resources, while providing added environmental, safety and security benefits for many applications.
According to the findings of the study on “Enhanced Use of Underground Space in Hong Kong” completed by the Civil Engineering and Development Department in March 2011, Hong Kong is particularly suitable for developing rock caverns from the geological perspective. The study has recommended a feasibility study on the relocation of Diamond Hill Fresh Water and Salt Water Service Reservoirs to caverns, with a view to releasing the existing site (about 3 hectares) for housing and other beneficial uses. The relocation site has been preliminarily proposed at the hillsides north to Chuk Yuen North Estate, Wong Tai Sin.