Meet the companies tackling nine of humanity's biggest problems -- and making millions saving us from ourselves.
Problem #5: Dirty Water
Problem #5: Dirty Water
The background: More than a billion people lack access to drinkable water. Nearly 5,000 children die each day from waterborne diseases like diarrhea, cholera, and typhoid.

The solution: WaterHealth International, based in Lake Forest, Calif., sells miniature water-treatment plants to the developing world. WaterHealth locates a source - a nearby river or well - and builds a delivery system to get the water to its garage-size WaterHealth Centre. There, water is piped through filters and a 15-pound ultraviolet disinfection device that removes all but .01 percent of bacteria and viruses.

The system has no moving parts, and the UV lamp needs just 60 watts of power, which can be supplied by a car battery. Installation costs a 6,000-person village about $10 per person.

The payoff: WaterHealth operates more than 500 systems in Asia, Africa, and Central America, delivering water to an estimated 500,000 people. The privately held company won't disclose its revenue, but its typical installation brings in as much as $50,000. WaterHealth expects to turn a profit next year.

The opportunity: WaterHealth estimates that there are about 2 billion people without access to clean water or whose water supplies could be improved with filtering.

Global Warming

Oil Dependency

Hunger and Malnutrition

Dirty Air

Dirty Water

Overfishing

Epidemics

Drug-Resistant Infections

Waste Disposal
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Market indexes are shown in real time, except for the DJIA, which is delayed by two minutes. All times are ET. Disclaimer Morningstar: © 2014 Morningstar, Inc. All Rights Reserved. Disclaimer The Dow Jones IndexesSM are proprietary to and distributed by Dow Jones & Company, Inc. and have been licensed for use. All content of the Dow Jones IndexesSM © 2014 is proprietary to Dow Jones & Company, Inc. Chicago Mercantile Association. The market data is the property of Chicago Mercantile Exchange Inc. and its licensors. All rights reserved. FactSet Research Systems Inc. 2014. All rights reserved. Most stock quote data provided by BATS.