Information on Desalination Plants

Only about 1 percent of the world's water is suitable for drinking and agriculture. Desalination plants turn saltwater into water fit for human consumption.

History

• Scientists have been tinkering with the idea of turning saltwater into potable water since the early 1900s. One of the first successful desalination plants was built in Freeport, Texas, in 1961.

Function

• Desalination works by putting a membrane--essentially a wall with tiny holes--into water, and forcing pure water onto one side and dissolved materials, such as salt, on the other.

Benefits

• Desalination plants create sources of fresh, potable water where not enough exists, in places with low rainfall, such as deserts, or, usually, because the surrounding area contains undrinkable seawater.

Fun Fact

• The potential for desalination plants is huge--in 2005, Harvard Business School estimated that the water industry does $400 billion in business each year (including sales and investment). By 2025, the United States will need about $500 billion in upgrades to its water system infrastructure--desalination plants could capture much of this spending.

Criticism

• The World Wildlife Fund believes that desalination plants emit too many greenhouse gases during the desalinization process and detract from the preservation of natural sources of fresh water--which might prove cheaper than building a desalination plant. In addition, the water waste from these plants, high in brine content and treatment chemicals, can kill off local marine wildlife, especially along coastal areas.