Few people in the world are more water-conscious than California farmers.

The state leads the nation in farm revenue and produces nearly half of the domestic supply of fruits, nuts and vegetables. It also boasts nine of the top 10 producing counties in the nation, according to the California Department of Food and Agriculture.

Yet California is one of the driest states in the U.S., getting an average of just 22 inches of precipitation annually compared with more than 40 inches for states like Missouri and New York. And, with nearly 40 million people, California is also the most populous state—meaning there's a lot of competition for that precious rain and snow.

How do the farmers make do with so little water? They use technology and the state's topography to stretch existing supplies as far as they can.

For more, see: Water, Water, Not Everywhere