Data centers need a lot of power to operate, and, depending on how they're cooled, a lot of water too. A recent poll by Gallup News found that seven in 10 Americans oppose local construction of AI data centers. Most data centers either use air or water, but Cook said because it's so hot in Texas, water is the preferred method. Just like how your body cools itself, some data centers use an air chiller to cool down that fluid, which can limit a data center's overall water usage to things like landscaping and flushing toilets. Not even state regulators know for certain how much water most data centers are using — and they have tried asking.