At this year's H2O Global Water Summit in Toronto, Canada, two hundred of the world's leading water companies and authorities gathered to assess the latest market developments. The event provided a telling barometer of opportunities and challenges in the water industry.

It's an interesting time to appraise the "blue segment" of green business. Over the past year, we have seen a torrent of water-related events that broadly impact society and industry: the Gulf oil spill; the completion of China's controversial Three Gorges Dam; the Mississippi flooding; and, most recently, the breakthrough of "Big Becky" under Niagara Falls. Big Becky is massive drill that has been boring bedrock for five years to provide hydroelectric energy to Canada. It is the largest renewable project of its kind in the world.

Despite these headline events, water has taken a back seat in sustainable business and cleantech. Over the past decade, the rallying cry of "water is the new oil" (or even the new carbon) has not materialized.

Yet with mounting water scarcity and water quality pressures, the convergence of water and energy issues, and the drive for greater resource efficiency, the market is clearly gaining momentum. Between 2005-2010, the Dow Jones Water Index surged 80 percent. Between 2007 –2010, it outperformed the S&P by over 20 percent.

There are already a large number of countries, industries and companies whose economics are critically reliant on water. And that number is going to increase exponentially in the next five years. Here's why:

The Current Market Need is Growing -- Fast

Water scarcity and water quality are already an issue in many parts of the world. Accelerating demand will put an already limited water supply under extreme pressure. Over the next ten years, demand is projected to increase 20 to 35 percent. By 2020, 37 percent of the world, developed and developing nations alike, will experience water stress.

The water predicament is all too easy to overlook in the U.S., where consumption exceeds 158 gallons a day per person, and users do not pay the true price of water. "Much of the world treats water with disrespect," observes Vikram Rao, Executive Director of the Research Triangle Energy Consortium. But the mindset is changing.

"We are already seeing the impact in Brazil, China, Russia, and Australia," said Steve Watzeck, Chief Marketing Officer of GE Water and Processing Technologies. "In the U.S., Montana and Wyoming are dealing with water issues and are harbingers of what is to come."

Water quality is equally pressing. Quality is fundamental to consumers, municipalities and industry. Over 70 percent of China's surface water is unclean. In North America, the rural and remote areas frequently face water quality problems.