THE BURNED OVER DISTRICT

The UN is predicting a 40% shortfall in needed water supplies around the world by 2030.

Many underground water reserves are already running low, while rainfall patterns are predicted to become more erratic with climate change. As the world's population grows to an expected 9 billion by 2050, more groundwater will be needed for farming, industry and personal consumption.

With "business as usual" the world is facing a "collapse in our global socioeconomic system," Richard Connor, lead author of the report, told Reuters.

The report predicts global water demand will increase 55 percent by 2050, while reserves dwindle. If current usage trends don't change, the world will have only 60 percent of the water it needs in 2030, it said.

Having less available water risks catastrophe on many fronts: crops could fail, ecosystems could break down, industries could collapse, disease and poverty could worsen, and violent conflicts over access to water could become more frequent.

"Unless the balance between demand and finite supplies is restored, the world will face an increasingly severe global water deficit," the annual World Water Development Report said, noting that more efficient use could guarantee enough supply in the future.

By 2050 two thirds of the world's population will be living in cities, and demand for water is expected to grow related to urbanization in developing countries. Urbanization means that access to safe water and adequate sanitation, although typically higher in cities, has decreased in the fastest growing urban areas.

One example is sub-Saharan Africa, where urbanization — often unplanned — is happening most rapidly. Here the proportion of people who have piped water on their premises has fallen to 34 percent from 42 percent since 1990.

"The spontaneous urbanization, which creates slums, makes it very difficult because of the layout of the slums to provide water," Joan Clos, executive director of the United Nations Human Settlements Program (UN-HABITAT), told Reuters.

If Nestle Coke & Pepsi have their way, that date may come much sooner. But if you have the bucks, you will be able to buy the necessary clean water from them.