Water rationing for four hours every four days during the 1960s is part of Hong Kong legend. Since then, we have had plentiful water supply from Guangdong, which like Hong Kong, is situated in the monsoon-blown south where there is heavy annual rainfall. It would appear that neither Guangdong or Hong Kong will ever have to worry about water supplies. This is wishful thinking, unfortunately.

Like Hong Kong in the 1960s, with rapid industrialization and growing population and probably together with climatic factors, Guangdong has suffered from perennial droughts in recent years, especially in the north-eastern part of the province. This year the situation seems to be quite severe and the Guangdong government issued a drought warning last month.

Now that there is a contract between Hong Kong and Guangdong which guarantees our supply of water, we have so much water that every year our reservoirs have to spill over millions of cubic meters of water into the sea. The current water supply situation in the region is expected to get worse, Hong Kong will soon be seen as wasteful and irresponsible.

This is surely not good for our image, and when the water supply contract comes up for renewal in the not too distant future, chances are that we might not get as much water as we desire. This is understandable because ultimately the Guangdong government will have to be accountable to its citizens for adequate water supply.

Our day of reckoning will come soon, and we will have to be prepared for it. I have lived through the horrible experience of water rationing, and I am sure we do not want it to happen again.

In the short run, we have to plug our pipes against leakage because according to official admittance as much as 20 percent of our water supply has been wasted this way. Some of our treated water can be used for street cleaning, etc., instead of being pumped into the sea. Our government has to launch a campaign to advocate more thrifty habits in the use of water.

Moreover, we will have to plan for a higher degree of water self-sufficiency. We should learn from Singapore which is desalinating sea water through reverse-osmosis. In fact our entrepreneurs have mastered the state-of-the-art technology in making semi-permeable membranes for the process.