Martin Riese is a certified sommelier—of water, that is. Instead of swirling, sniffing, and savoring fine vintages, he judges the unique qualities of H20s from around the world.

Riese had always noticed that tap waters in different cities have their own distinct tastes.  However, it wasn’t until he entered the restaurant industry that he realized there was an upscale market for the world’s most plentiful beverage. Ten years ago, while working at a Berlin eatery called First Floor, a customer approached Riese about the menu’s limited water selection.

“We offer a selection of liquors, beers and wines, but when it comes to water, it’s mostly just sparkling, flat or tap,” Riese told Eater. “Not even the water brand is given. It occurred to me that we have to give people options when it comes to the healthiest beverage on this planet and thus I created my first water menu.”

First Floor introduced a water menu the next year, and Riese honed his expertise on the beverage. In 2009, he published a book called The World of Water. Soon after, he became certified as a water sommelier through the German Mineral Water Trade Organization.  In 2011, he moved to Los Angeles, where he created water menus for restaurants like Ray’s & Stark Bar and Patina Group. Today, he's known as the world's only water sommelier. 

What’s in a “water menu,” you might ask? According to Riese, Patina Group’s water menus offers samplings of specialty bottles from across the globe, including different spring and mineral waters. Like wine, the origin, taste, and prices can vary; a bottle retails anywhere from $8 to $20. (The latter is for 15,000-year-old glacier water from Canada.)

Another similarity to wine: Some waters taste different from others thanks to terroir, or the land they come from. Water can be smooth or complex, fruity or salty, and can affect the final taste of a food or drink recipe. It can also be limited in quantity or difficult to procure. In short, water is not a one-taste-fits-all substance.

If you're interested in learning more about the wonders of water, check out a video from Zagat, in which Riese walks a skeptical taste tester through the subtleties of his favorite beverage. 

[h/t Eater]