While most of us take water pretty much for granted, cleaning it and making it safe is big business that could spell significant profits for investors. Ecolab (NYSE:ECL), the world's largest provider of services and chemicals used in water treatment, recently announced its plans to expand across the globe. Similarly, despite the depressed prices we have seen for rare earth materials, Molycorp (NASDAQOTH:MCPIQ) is finding a measure of success in water treatment.

In the video below, Fool.com contributor Doug Ehrman discusses some of the trends that impact the demand for water and how each of these companies can help you to benefit from participating in the shift.