When unveiling the Territorial Development Strategy Review 1996 last month, Secretary for Planning, Environment and Lands Bowen Leung said Hong Kong's current population of 6.3 million may increase as much as 8.1 million in the next 15 years. It was ironic that Mr Leung was talking, in the same breath, about sustainable development. Packing more than six million people into such a small area is no mean feat. Consequently Hong Kong is one of the most densely populated places on the planet. In the past decade, living standards have improved as a result of economic advancement. At the same time, people began demanding a cleaner, healthier and more spacious environment. The current environmental degradation is already a source of concern. Further uncontrolled population expansion would bring disastrous consequences to our quality of life. Hong Kong is an incredibly overcrowded place. Many people live in tiny cubicles and work in a congested environment. The Government's reluctance to develop more recreational facilities in the New Territories and outer islands means people have few places to go at weekends. When taken to task, Principal Government Town Planner Ted Pryor said the eight million population projection is the 'worst-case scenario', adding it is based on past trends. According to the Census and Statistics Department, population growth in the past few years was faster than expected. The department had projected the mid-1995 population to be 5,852,000. It turned out to be 6,164,700 - 312,500 more. The discrepancy was mainly due to immigration, since Hong Kong has one of the lowest birth rates in the world. Another reason was the increase in the daily quota for legal immigrants from China. Between 1983 and 1991, the quota was set at 75 people a day. That went up to 105 in 1994 and to 150 in July 1995. In addition, hundreds of Chinese enter Hong Kong daily on two-way permits which enable them to stay for a specified period. Government figures show that between 1981 and 1992, there was a persistent net outflow of Hong Kong residents, that is more people leaving than returning. From 1981-6, the net annual outflow averaged 18,000. The level began to rise in 1987 and reached 48,000 in 1990. That sparked off concern about a brain drain. The trend was reversed in 1993 when many immigrants returned after acquiring foreign citizenship. The net inflow reached a high of 50,104 in 1995. After the change of sovereignty next July, the population pressure will become more intense. In 1994, it was estimated there were 64,000 children in China who will have the right of abode in the Hong Kong Special Administrative Region under the Basic Law. It is also estimated that there are as many as 400,000 people in China with family connections here, some of whom are spouses of local residents. Under Hong Kong law, local people who marry mainland Chinese cannot bring their spouses here. The wait to come is often more than 10 years and the system is administered by the Chinese authorities. Such an undesirable system has led to many split families and spawned heart-rending stories. Last month, a mainland woman visiting her husband on a two-day permit leapt to her death with her two children. Confronted with such tragedy, some people say the split families should be reunited immediately. But can our social infrastructure withstand such a population increase? This is a minefield but it must be explored. We owe it to ourselves and to the next generation to get to grips with this sensitive problem.