Cavern Development - 岩洞發展

Q1.	What is “underground space” and “rock caverns”?
A1.	“Underground space” includes purpose-built, underground rock caverns as well as other large basement-type excavations formed by "cut and cover" methods. “Rock caverns” refer to large man-made spaces in rock.
Q2.	What types of facilities are suitable for rock cavern development?
A2.	Cavern construction is an established technology that has seen continual improvement and expansion in its applications. A diverse set of uses including municipal facilities (e.g. sewage treatment works, refuse transfer stations and service reservoirs), storage facilities (e.g. archives, oil and gas, and food), community and recreational facilities (e.g. retail, sports halls, swimming pools, gymnasiums and bowling alleys), and special facilities (e.g. data centres, civil defence and laboratories) are suitable to be housed in rock caverns. Caverns have also been built as part of mass transportation networks in various cities around the world. Many cavern schemes have been successfully built around the world with notable examples in Canada, the USA, Finland, Norway, Sweden, Switzerland, China, Singapore, Japan, and Korea. In Hong Kong, a few purpose-built rock caverns were constructed in the mid-1990s to accommodate government facilities to meet the needs of the community, namely the Stanley Sewage Treatment Works (1995), Island West Transfer Station (1997) and Kau Shat Wan Government Explosives Depot (1997). The re-provisioning of two existing salt water service reservoirs (i.e. Western Salt Water Service Reservoirs) near the University of Hong Kong in rock caverns in 2009 released land for its Centennial Campus development. The West Island Line temporary explosive magazine at Victoria Road is also a rock cavern scheme. Caverns have also been built as part of the mass transportation network in Hong Kong such as the Tai Koo and Sai Wan Ho MTR Stations. The Lei Tung Station of the South Island Line and the Sai Ying Pun and University Stations of the West Island Line will also be housed in rock caverns.
Q3.	What are the benefits of rock cavern development?
A3.	Land is a scarce resource in Hong Kong. Cavern development could provide creative solutions in easing the pressure on land shortage, particularly in the urban area. For example, locating public facilities that either currently occupy or will occupy surface sites in caverns could release the land for other beneficial uses. Furthermore, given the increasing public concerns on NIMBY (Not In My Backyard) facilities, the utilization of rock caverns can provide effective solutions for housing these facilities.
Q4.	Why do we need a programme to relocate government facilities?
A4.	We need to develop an effective plan for relocation of suitable government facilities to caverns in a systematic manner, thereby gradually releasing the surface land for other beneficial uses. We would consult with relevant government departments to identify and select suitable government facilities and develop a workable relocation programme that meets the needs of government departments as well as community expectations.
Q5.	Why do we need to prepare Cavern Master Plans?
A5.	The purpose of preparing Cavern Master Plans is to delineate strategic cavern areas that are to be reserved, so that their potential for cavern development would not be compromised by future development projects.
Q6.	Why do we need policy guidelines for rock cavern development?
A6.	In the mid-1990s, a few government facilities have been purpose-built in rock caverns to meet the needs of the community. These projects have demonstrated that rock caverns can be a very effective and viable solution offering added environmental, safety and security benefits for many applications. Despite these successful projects, the cavern option is generally considered as a last resort by the project proponents. Therefore, we need to formulate a more proactive policy for cavern development to mandate government departments to consider the cavern option in the initial planning stage for suitable government facilities. In addition, some private sector facilities (e.g. warehouses, logistics centres, data centres and wine storage) are suitable to be housed in rock caverns. These businesses demand high land take for their operations. Rock cavern development can help address their space requirements, thus yielding new business opportunities. In view of the above, we need to develop relevant policy guidelines and mechanisms to enable private sector to participate in rock cavern development.

What are Rock caverns? Rock caverns refer to large man-made spaces in rock,
which offer many beneficial applications in terms of land uses