No, not for an everyday query. The figure comes from two studies by the University of California, Riverside: around 500 mL for 10 to 50 GPT-3 responses (2023), then ~519 mL for a 100-word email generated by GPT-4 (2024). Both count total water, meaning cooling plus the water used to generate the electricity. Repeated as "half a litre per message", the figures are applied to a different scope and a different model: an everyday query on a recent model evaporates a few tenths of a millilitre in cooling.
Read the source article: How much water does ChatGPT use? A few drops per query