Visualizing US Water Use by Sector

The United States withdraws roughly 322 billion gallons of water every day, according to survey data from the US Geological Survey. That number, from the most recent comprehensive USGS survey, is actually the lowest recorded since before 1970, capping two decades of decline driven by efficiency gains and a shifting energy mix.

Who takes the most

Thermoelectric power and irrigation are the two largest uses of water in the US, accounting for the overwhelming majority of daily withdrawals. In 2015, power plants pulled 133 billion gallons per day and agriculture 118 billion gallons per day, together representing about 78% of all withdrawals.

Not all use is the same: A critical distinction exists between withdrawal and consumption. Power plants withdraw enormous volumes of water to cool steam turbines, but most of that water is returned to its source. Agriculture is the inverse: irrigation water largely evaporates or is absorbed by plants, making it genuinely gone from the system. On a consumption basis, agriculture is by far the dominant user.

Why is water use going down?

The biggest story in US water consumption over the past two decades is the decline from thermoelectric cooling. The electric power sector's water withdrawals fell 10.5% from 53.1 trillion gallons in 2019 to 47.5 trillion gallons in 2020, continuing a downward trend driven by the shift from coal to natural gas and renewables, as well as less use of once-through cooling systems.

The numbers are stark at the plant level: natural gas combined-cycle generation requires about 2,803 gallons of water per megawatt-hour, compared with 19,185 gallons per megawatt-hour for coal, according to 2023 estimates from the US Energy Information Administration. Solar and wind require almost nothing.

Do data centers use a lot of power? Contrary to popular belief, they don’t.

Scientists at Lawrence Berkeley National Laboratory estimate US data centers used about 228 billion gallons of water in 2023, with about 17 billion gallons going directly to cooling servers and another 211 billion gallons tied to electricity generation. 

Putting aside that most water used for data centers is withdrawal, and so gets returned to its source, all data centers combined account for less than 1% of water used for agriculture, most of which is consumption.