Shortage of land is a lingering issue for Hong Kong. In recent years, the government has been looking into the development of rock caverns to increase land supply. After four years of study, a Cavern Master Plan has been compiled, and delineates 48 Strategic Cavern Areas. The plan is to relocate unpopular facilities and recreational sites with low demand, in order to release the original sites for other land uses.
Exploring underground space is not new to Hong Kong. The construction of the Mass Transit Railway stations in the 1980s was a pioneering example. Later on, different facilities including a sewage treatment plant, refuse transfer station, service reservoir and explosive depot were also sited underground.
Most of the Strategic Cavern Areas listed in the Cavern Master Plan are beneath hills, many of which are in country parks. It is likely that adverse impacts will accompany during the construction and operation of the cavern facilities. The issue should not be overlooked. It is crucial that portal access should be placed outside the country parks, so that new roads need not be built inside country parks, and impacts of vehicles on country parks can be minimised. Impact assessments on hydrology, erosion and ecology in the area must also be properly carried out. Rock and rubble from the evacuation of caverns should also be reused, in order to reduce the waste and other environmental problems caused by the work.
Environmentally friendly factors should be taken into account in cavern design. For example, natural ventilation and lighting can be adopted, to reduce energy consumption by mechanical ventilation and lighting systems. Water recycling systems can also reduce the need for transport of clean water and wastewater.
While reclamation and developing country parks arouses much public concern, the exploitation of caverns seems to be less controversial. However, any form of land development is inevitably accompanied by environmental issues. With our unrelenting desire for development, what will be our last resort when all the land, inshore waters and even underground space has been exploited?