Increasing industrial, household and agricultural activities have seriously polluted water bodies in nearly all urban centers of the developing world. By 2011, water from more than half of China's largest lakes and rivers were declared unfit for human consumption, and more than half of the groundwater in northern China was polluted.

In India, a 2013 report shows that water in nearly half of its 445 rivers are too polluted for human consumption. In fact, water from an overwhelming number of water bodies in India can no longer be used without expensive treatment. As water becomes increasingly scare, the economic, social, health and environmental costs of such heavy contamination are rising steadily. In some countries, the real costs of poor water management can add up to 5 percent of GDP.

If the current trends continue, the situation can only get worse. Nearly two-thirds of industrial companies now say water poses a substantial risk to their business.

Millions of people die every year because of water-related diseases. Droughts and floods inflict billions of dollars in damages year after year. The United Nations has estimated that droughts are the world's costliest natural disasters, inflicting $6-8 billion annual losses. Floods cause major damage, too, in terms of lives and money. All this can be significantly reduced by better water management.

As poet W.H. Auden said: "Thousands have lived without love, but not one without water."

Peter Brabeck-Letmathe is the chairman of the board of Nestlé, and chairs the 2030 Water Resources Group. Asit K. Biswas is distinguished visiting professor at Lee Kuan Yew School of Public Policy, Singapore, and co-founder of the Third World Centre for Water Management, Mexico.