US datacenters tripled their water footprint in 10 years

Datacenters in America used about 17 billion gallons of water during 2023, triple the amount they used a decade earlier in 2014, according to an estimate from US Congressional Research Service (CRS).

In a recent report published by the Library of Congress, the CRS casts an eye over how server farms use water, looks at potential options to reduce this, and discusses the current federal role in overseeing the use of H2O by operators.

The CRS notes the federal government does not systematically assess all water use by the industry - part of the problem is that water usage data is often collected by state-level bodies.

Sudden upswing The report says the AI craze has led to a massive surge in datacenter construction since OpenAI released ChatGPT at the end of 2022, which triggered a wave of demand for generative AI and large language models (LLMs).

Many new-build data halls are also home to specialized AI hardware, which typically burns much more power (and consequently has greater need of cooling) than older infrastructure.

The CRS data says water use in US bit barns had already tripled by 2023, which is the year that the AI-driven infrastructure build boom took off, and it is probable that liquid intake has increased further since then.

However, direct use of water - the amount used at the facility itself for thermal regulation, rather than indirect use during off-site power generation - is estimated to make up a relatively small proportion of total US water consumption of about 2 percent.

Indirect water consumption via electricity generation made up more than 80 percent of the datacenter's overall water use, the study found.

CRS doesn’t go into too much detail about actual cooling systems, noting that datacenters may rely upon different types of technology depending on the size and location of the facility, and the thermal regulation needs of the IT kit.

Liquid cooling systems can be more efficient than air-cooled systems, but may not be cost-effective for smaller campuses.

Cool runnings As The Register has also previously explained, there are trade-offs between water consumption and power usage.

Evaporation-based cooling systems are generally more energy efficient than air-cooled chillers or other waterless systems, but use up much more water.

Which system gets chosen may depend on location and climate as much as anything else.

Datacenter operators may draw their liquid from various sources, typically municipal drinking water systems, but also treated wastewater or direct withdrawals from surface water or groundwater.