AI Water Use: One Almond vs 800 Prompts

Is AI's water use a reason not to use it in my business?

No. And if the water headline is the thing holding you back, you have not done the one piece of math that settles it.

A panic is a feeling about a number nobody has looked up. A decision is what you do after you look it up.

So here are the two numbers. One California almond takes about 12 liters of water to grow. One AI prompt takes about 15 milliliters. Divide one by the other and you get 800 prompts to one almond. I recorded this Fargo Walks episode in front of my old elementary school in Canandaigua, New York, because the math is elementary. What is not simple is where the numbers come from, so the rest of this page shows the work.

How much water does one AI prompt use?

It depends on who is counting, and that is the whole story.

The most cited independent estimate comes from researchers at UC Riverside and UT Arlington. Their paper "Making AI Less Thirsty" (Pengfei Li, Jianyi Yang, Mohammad A. Islam and Shaolei Ren, first posted April 2023 and revised March 2025) found that the model behind ChatGPT consumes "a 500ml bottle of water for roughly 10 – 50 medium-length responses, depending on when and where it is deployed." That works out to 10 to 50 milliliters per response.

OpenAI's own number is far lower. In his June 2025 post "The Gentle Singularity," Sam Altman wrote that the average ChatGPT query "uses about 0.000085 gallons of water; roughly one fifteenth of a teaspoon." That is about a third of a milliliter.

A study published September 1, 2026, and cited by PolitiFact, put ChatGPT's use "between 0.6 and 17 milliliters per prompt."

I used 15 milliliters. It sits inside the independent range and near the top of the newest estimate. It is roughly fifty times the company's own figure. I picked it on purpose. When you are testing a fear, use the number that goes hardest against your case. If the answer still holds, you are done.

How much water does one almond use?

PolitiFact, reviewing a 2019 study in the journal Ecological Indicators (Fulton, Norton and Shilling), summarized it in one line: "A 2019 study found that the process of growing a single California almond requires 3.2 gallons, or 12 liters, of water."

That 12 liters is the full water footprint. It counts rain, irrigation and the water it takes to dilute farm runoff. PolitiFact adds the narrower figure: "About 6.3 liters of the total came from fresh water used for irrigation."

I used the 12. Same rule as above. If you want to argue the almond side down, use 6.3 and my prompt figure, and you still get 420 prompts to one almond.

What did Sam Altman get wrong this week?

On September 1, 2026, on the Sources Podcast, Altman said: "For every 38,000 ChatGPT queries, that is the same amount of water that is used in the production of a single almond in California."

Three days later PolitiFact's Caleb McCullough checked it and wrote: "We rate it Mostly False." Altman's 38,000 only works if you accept OpenAI's unaudited one-fifteenth-of-a-teaspoon figure. PolitiFact's own read of the independent research: "Based on some estimates, you'd need anywhere from 1,000 to 10,000 conversational AI prompts to equal the 6 liters of fresh water used to grow one California almond."

Notice where my number lands. 800 is below PolitiFact's floor. I gave AI less credit than the fact-checkers did, and the almond still wins by hundreds to one.

That is the lesson for you as an owner, and it has nothing to do with almonds. Do not take the vendor's number. Do not take the headline's number either. Find the two figures behind the claim, pick the ones that go hardest against what you want to believe, and divide.

What is my own number?

I counted. On Saturday, September 5, across every AI tool I touched, I sent 79 prompts. About 60 in a sixteen-hour Claude build session, 16 in the one-hour session where this page and the video upload got done, 2 in Claude Code, and 1 in ChatGPT. At 15 milliliters each, that is about 1.2 liters of water. Under a tenth of one almond.

That was an unusually heavy day, not a typical one. On a normal day the number is smaller. That is the whole count, and I am not going to round it up to make a point.

What this does not mean

It does not mean data centers are free. They use real water and real power, and the UC Riverside paper is clear that the amount depends on where and when the work runs. Those are questions for the companies building them and the towns hosting them.

It means that for you, one owner sending prompts at a desk, the per-prompt water cost is not the thing to decide on. You already made a bigger water decision at breakfast.

The decision

Stop letting a headline make a business call. Find the two numbers, divide, and then decide on the work AI does for you.

Sources

• PolitiFact, Caleb McCullough, "Sam Altman says growing a single almond equals 38,000 ChatGPT queries," September 4, 2026. Rated Mostly False. Source of the Altman podcast quotation, the 12-liter and 6.3-liter almond figures, and the 1,000 to 10,000 prompt range.
• Pengfei Li, Jianyi Yang, Mohammad A. Islam, Shaolei Ren, "Making AI Less 'Thirsty': Uncovering and Addressing the Secret Water Footprint of AI Models," arXiv 2304.03271, April 2023, revised March 2025. "A 500ml bottle of water for roughly 10 – 50 medium-length responses."
• Sam Altman, "The Gentle Singularity," June 2025. "About 0.000085 gallons of water; roughly one fifteenth of a teaspoon."
• Julian Fulton, Michael Norton, Fraser Shilling, "Water-indexed benefits and impacts of California almonds," Ecological Indicators, Volume 96, 2019.
• Almond Board of California, "Water Footprint + Almonds" factsheet, 2020. Summarizes the Fulton study, irrigation component 1.7 gallons per almond.
• Jeff Fargo, Fargo Factor Insight: Challenge AI Output Before You Trust It
• Jeff Fargo, Fargo Factor Insight: You've Known About AI for Two Years. What Are You Waiting For?

Transcript

Verbatim from the Fargo Walks clip, as recorded.

Shout out to Canandaigua Elementary School, my alma mater, fourth, fifth, and sixth grade. It takes 12 liters of water to grow a California almond. It takes 15 milliliters of water to generate one AI prompt. That means it takes 800 prompts to one almond. And that's what everybody is panicking about. I'm Jeff Fargo. I can help you streamline and scale with AI. Go forth.

Jeff Fargo is the founder of Fargo Factor and host of Fargo Talks. Fargo Factor advises established businesses on AI Search Authority, AI Decision Systems, and selective AI-enabled implementation.