| By Michelle Ma You might not realize it, but every time you ask an AI chatbot a question, a data center is forced to guzzle water. To be precise, a data center requires about a 500-milliliter bottle of water to generate 10 to 50 medium-length GPT-3 responses, according to one analysis. Generating an image uses substantially more water than text, and a video uses dramatically more than an image. Here’s why: Data centers need a way to cool their servers to prevent them from overheating. One of the main methods of doing this is through cooling towers that evaporate water. Data centers also consume water indirectly through electricity generation, since the power plants that feed them energy also need to be cooled. This is all well-documented, and there’s been a ton of research out there on how much water data centers consume in aggregate. But my team wondered where these data centers were in relation to local water resources. After all, we know data centers are often strategically sited near robust energy resources: Would the same be true for water?  A data center in Odessa, Texas. Photographer: Justin Hamel/Bloomberg To answer this question, my colleague Leonardo Nicoletti got his hands on data from market intelligence firm DC Byte that showed us the existing and planned data centers globally. He mapped that over data from the World Resources Institute illustrating global water stress – which quantifies competition over water resources from different sectors like agriculture, cities and industrial users. What he found was surprising: Data centers in the US and around the world are disproportionately built in highly water-stressed areas. The AI boom has only made it worse: Two thirds of new data centers built or planned since 2022 are in places that already have high competition for scarce water resources. We wanted to know why this was the case, and so I spoke to water researchers and data center experts to understand what was happening. Cheap, clean energy is a much higher priority than water. In fact, water is often the last consideration when it comes to siting data centers. And when you combine that with the fact that the sunniest places with the most plentiful renewable resources tend to also be the driest, you have a problem. Tech companies aren’t ignorant to this dilemma. A number of them have proposed or implemented ways to cool their servers that draw less water. My colleague Dina Bass talked to them for this story. She found that there’s often a tradeoff between cooling systems: The ones that use lots of water require less energy, and vice versa. It’s a tricky balance. To find out more about how data centers consume water and what companies are doing to fix the problem, check out the story. | 
