This post is part of a special report, A Dozen Ways to Play an Obama Building Boom.

"Stocks in the water sector could soon flood their shareholders with a deluge of profits," says value investor Nathan Slaughter. In his Half -Priced Stocks, he explains, "Even in the 21st century, UNICEF reports that a staggering 1.1 billion in emerging markets still lack access to safe drinking water.

"And here in the U.S., the EPA has said we need to spend $275 billion to replace aging facilities -- including 800,000 miles of leaky, corroded pipeline that haven't been upgraded since the 1800's in some places.

"We see an incredible opportunities for the companies trying to combat the problem, particularly those involved with water distribution pipes, treatment facilities, purification technologies and other critical infrastructure.

"My top play in the sector is Veolia Environnement (NYSE: VE), a global juggernaut with $45 billion in annual revenues, operating on every continent.

"From humble origins supplying water to Parisians over 150 years ago, Veolia has grown to become the world's largest water utility. Today, it provides water and sewerage services to 130 million people in nearly 60 countries worldwide.

Two leading global experts have both turned bullish on France's Veolia Environnement (NYSE: VE). Vivian Lewis, in her Global Investing, notes, "Veolia is the way to play the 'water works square' on the monopoly board."

Nicholas Vardy, editor of Global Stock Investor suggests, "The smart money is betting that water may be the 'oil of the 21st century.' And Veolia is my number one way to profit from this global megatrend."

Vivan Lewis says, "We recommend buying French water and sewage conglomerate Veolia at current prices; the stock has been brought down by niggling Euro-concern about its levels of debt. The company is also being penalized for acquisitions.

"Veolia is the former Générale des Eaux, a municipal service firm. This history creates an image problem for VE which is seen as a utility.

"Our main reason for the buy, apart from price, is that this is a fast growing company with good earnings in a hot sector. In 2007, VE had revneues of euros 32.6 bn, up 14% on which its recurring net profit fost 22.5% to euros 933.2 mn. Earnings per share were euros 2.16, up 13.7%.

"Another reason for liking VE is that it is moving into China big-time, with waterworks in Tianshin and Shibai and environmental service in Juijiang. All in all, France still represents 44% of sales and the rest of Europe 36%. VE does about 10% of its business in the U.S. and the Chinese are part of the remainder.