Fred de Sam Lazaro:

From commerce to fishing, transport and rice production, the mighty Mekong River is the lifeblood of Southeast Asia.

But, today, one of the biggest businesses on the river in Cambodia is dredging it for sand to make concrete, feeding one of the biggest industries in the developing world, development.

Nowhere has demand for sand been greater than in Asia. Across this sprawling continent, tens of millions of miles of new roads have been built connecting hundreds of millions of new homes. Construction has driven the large economies, like China and India, and the smaller ones, like Cambodia, whose cities, like Phnom Penh, have joined the building binge.

Skyscrapers, malls and apartments crowd the skyline, much of it investment from China, fueling an economy that's grown at a healthy 7.5 percent each year since 2005.

Monyrath Yos of the government ministry overseeing mineral resources says sand mining plays an important role.