Water is essential to our survival and we use a lot of it, especially in the U.S. On average, the U.S. uses 355 billion gallons of water per day. Most of us have access to it at our fingertips. It’s usually as easy as turning on a faucet, or pressing a button. But what lies beyond the plumbing connected to our sinks, washing machines and showers? We conducted extensive research to create the interactive map below, identifying where each person’s water comes from, no matter where you are in the continental U.S.

Water is either sourced via groundwater or surface water. Two-thirds of our water comes from surface water, which includes areas of land that rain and snow melt flow through, like streams, rivers, and lakes. We mapped out 18 of the largest surface watershed regions in the U.S., which can be viewed above. Surface watersheds supply our nation with the bulk of its water including water for drinking, agriculture and manufacturing.

Groundwater is located in the soils and cracks in rock underground, which is pumped from wells that are drilled into underground aquifers. Like surface water, groundwater is used for drinking, irrigation, agriculture and manufacturing, but only one-third of our total water usage comes from groundwater.

Surprisingly, thermoelectric power plants are the biggest consumers of water, guzzling 159 billion gallons of water per day. Irrigation is the second largest consumer of water. More than 117 billion gallons of water is used for growing crops and maintaining landscapes across the country. Currently, California, Texas and Idaho are the nation’s largest consumers of water using 38, 25 and 17 billion gallons per day, respectively.

While the planet may never run out of water as a whole, many countries, states, and cities face water scarcity as well as crippling droughts. Around the world, more than a billion people live without an adequate amount of safe, clean water. By 2025, huge populations are projected to be facing water stress or water scarcity. Even though most of us aren’t affected by water shortages, it’s important to keep those numbers in mind the next time we reach for the faucet.