Water and Data Centers: What’s Actually True

Water use is one of the most common concerns raised about data centers — and it’s a fair one to ask. The honest answer is that it depends significantly on which kind of facility you’re talking about, and the difference between an older design and a modern one is substantial.

Where the High-Water-Use Numbers Come From

Most of the headlines about data centers consuming millions of gallons of water per day trace back to older facilities using evaporative cooling. The principle is similar to a swamp cooler: water is sprayed over warm equipment, it evaporates, and the evaporation carries the heat away. It works, but it uses significant amounts of water. A large legacy facility can consume several million gallons per day.

That’s where the reputation comes from. It’s a real number for that type of facility — but it’s not how most data centers being built today are designed to operate.

How Modern Facilities Are Different

Newer data centers are increasingly built with air cooling or closed-loop liquid cooling systems. A closed-loop system works on the same principle as a car radiator: coolant circulates through a sealed system, pulls heat away from equipment, and is cooled by airflow. The same fluid stays in the loop — day-to-day water consumption is near zero.

Air-cooled systems skip water almost entirely, using fans and refrigerant to manage heat. Radius DC’s Nashville I facility uses a closed-loop cooling system specifically designed to minimize water consumption — a decision that reflects both good engineering and the water stress profile of the markets we operate in.

Cooling Technology: Three Approaches

• Evaporative cooling — older design; uses significant water; still common in legacy facilities
• Closed-loop liquid cooling — fluid recirculates in a sealed system; near-zero daily water use
• Air cooling — no water in the cooling process; uses fans and refrigerant

Most new data center construction, including Radius DC’s purpose-built facilities, uses closed-loop or air cooling.

Putting the Numbers in Context

Even for facilities that do use water, comparison matters. A single 18-hole golf course typically uses around 370,000 gallons per day. A single auto assembly plant uses 300,000–600,000 gallons per day. A modern air-cooled or closed-loop data center uses near zero.

A data center is not categorically a large water consumer. An older design can be; a modern one often isn’t.

The Honest Tradeoff

There is a real engineering tradeoff involved. Historically, air cooling required more electricity than evaporative systems — the choice traded water consumption for power consumption. That gap has narrowed considerably with advances in cooling technology, but it remains a real design consideration. In water-stressed regions, the industry has moved decisively toward air and closed-loop designs. In water-rich areas, some operators still use evaporative systems because the efficiency math supports it.

The technology has changed materially, and the numbers from older or larger facilities do not necessarily reflect how a facility being designed and built today will actually operate.

Questions Worth Asking

If a data center is being proposed in your area, these are reasonable questions to put directly to any developer:

• What cooling system will this facility use?
• What is the projected daily water consumption at full load?
• Where will that water come from — municipal supply, reclaimed water, or a private source?

Straightforward answers tell you more than any brochure. If you have questions about how Radius DC’s facilities are designed, we’re happy to answer them directly at radius-dc.com/connect.

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