Based on the aggregated intelligence of 170,000-plus investors participating in Motley Fool CAPS, the Fool's free investing community, water and air purifying systems specialist Calgon Carbon (NYSE: CCC) has earned a respected four-star ranking.

With that in mind, let's take a closer look at Calgon's business and see what CAPS investors are saying about the stock right now.

Calgon facts

Headquarters (Founded) Pittsburgh (1942)
Market Cap $857.7 million
Industry Commodity chemicals
Trailing-12-Month Revenue $444.7 million
Management

CEO John Stanik (since February 2003)

CFO Stevan Schott (since July 2010)
Return on Equity (Average, Past 3 Years) 12.8%
Cash/Debt $45.0 million / $23.6 million
Competitors

3M (NYSE: MMM)

General Electric (NYSE: GE)

Siemens (NYSE: SI)

Donaldson Company (NYSE: DCI)

Sources: Capital IQ (a division of Standard & Poor's) and Motley Fool CAPS.

On CAPS, 94% of the 308 members who have rated Calgon believe the stock will outperform the S&P 500 going forward. These bulls include CAPS member Reddrummer and All-Star Geofiz, who is ranked in the top 10% of our community.

This past summer, Reddrummer summed up the Calgon bull case: "Boring but profitable small company with good growth prospects. ... [P]eople always need clean water and air. As regulation on pollutions increase, so should [Calgon's] profits."

Calgon remains one of our community's favorite plays on the distressing trends in water availability and drinkability around the world. With a market cap of less than a billion, Calgon's three-year compound revenue growth (10.4%) tops that of much larger rivals like Siemens (5.6%), GE (-1.3%), 3M (2.3%), and Donaldson (-0.7%). Calgon also sports a lower debt/equity ratio than each of those same rivals, so it seems like a relatively safe bet, as well.

CAPS All-Star Geofiz elaborates:

A leader in a field that is destined to expand in the coming years. Revenues and [free cash flow] have increased steadily over the past couple of years, while margins have been squeezed just a bit. Beautiful balance sheet, with low, well-covered debt. [Calgon], along with [Flowserve (NYSE: FLS)] and a small, speculative investment in [Tri-Tech Holding], comprise my 'water portfolio.'

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