The harsh necessity of "Coping with Water Scarcity" - the theme of this year's World Water Day - becomes all too real with the mighty Yangtze River dropping to such a low level that some sections are no longer navigable.

Just two days ago, the global nature protection group WWF warned that the Yangtze and the Mekong are among the world's major rivers at risk of drying out because of climate change and human activities.

This brings home the urgency of tackling a crisis which will pose a threat to the very existence of human life.

In China, water scarcity has already become a reality for both residents and industry in more than 100 cities and many rural areas in the western and central regions.

To tackle water shortages in the northern part of the country, a gigantic project is under way to transfer water from the Yangtze and its branches to the north. There are other projects to transfer water from the Yellow River and other waterways to places in need of water, even though both the Yangtze and Yellow rivers have been suffering from water shortages.

These projects could help or they could increase these mighty rivers' danger of drying up. In any case, the measures will not quench the thirst in many parts of the country.

What makes the diminishing water supply even worse is the contamination of waterways and underground water by untreated sewage and waste water discharged by enterprises and urban drainage systems.

A study last year predicted that water in the Yangtze would be completely unusable in 10 years unless effective measures are adopted to stop the discharge of untreated waste water.

So even more important than the diversion of water are efforts urgently needed on two fronts: to adopt clear-cut measures to conserve water both in industrial production and in residents' daily use; to impose penalties severe enough to exert pressure on enterprises to spend money treating their waste water before discharging it.

We have done a great deal in these areas, such as increasing water prices to make residents more aware of the need to conserve water and intensifying crackdowns on enterprises that do not build sewage treatment plants or leave such facilities unused to save money.

This uphill battle urgently calls for more efforts on both fronts.

(China Daily March 22, 2007)