Cerahelix of Orono, Maine, which manufactures filters from renewable ceramic materials. The filters are used to make products out of organic materials that can be used for fuel. The filters also can help re-use recyclable materials and purify water.
Drop Water, a California company that transports bottled water in a more energy-efficient way, which requires only half the energy to bottle, and 1/30th of the cost to transport to bottled-water kiosks.
Folia Water, a Menlo Park, Calif., wholesale technology maker of paper filters for the 3 billion people around the world who make between $2 and $10 per day and need a very inexpensive way to have safe water for drinking.
GeoInteractive, based in Sydney, Australia, which deploys intelligent robots and autonomous floating drones for large sewers rather than people to inspect sewers, allowing employees to examine the sewers from their offices.
Micronic Technologies, based in Wise, Va., develops MicroEVAP, which it calls the sustainable water-purification technology. It uses no membranes, filters or chemicals to eliminate "virtually all contaminants from practically any source water."
Water Warriors, based in Cincinnati, works to solve world sewage problems using innovative approaches to traditional water-treatment methods. Dr. Rakesh Govind, the company's chief technology officer, is a professor of chemical engineering at the University of Cincinnati.
WINT (an abbreviation of Water Intelligence), of San Francisco, helps with water metering and data analytics for commercial real estate and utilities to help them detect inefficiencies in their systems, as well as leaks, in real time.