← Back to context

Comment by simonw

6 months ago

> The author dismisses 905M gallons in Maricopa County as "only 0.12%" of county use, but in a desert already overdrawing groundwater, that's 905M gallons unavailable for human needs.

Can you help explain what 905M gallons of water means?

My biggest problem with the data center water debate continues to be people throwing around big scary numbers like that without attempting to provide context for them.

(I found one estimate that the average US resident uses 30,000 gallons per year, which would make 900,000,000 gallons the same as 30,000 people.)

4 comments

simonw

Reply
relaxing  6 months ago

So imagine 30,000 people suddenly appear in the empty lot next door needing water.

  • ben_w  5 months ago

    I'm not trusting the linked blog itself, so I looked up the sources it used. The blog is claiming:

    > estimates that data centers in Maricopa County will use 905 million gallons of water in 2025

    One reason I don't trust this blog, is that this text links out, but the link itself ends in:

      utm_source=chatgpt.com#:~:text=At%20the%20state,annual%20water%20use.

    And when I follow through, the actually linked text (on domain circleofblue.org) says:

      Walsh’s research at Bluefield indicates that data center water consumption in Arizona in 2025 will be roughly 905 million gallons

    Not being an American, I had to look up Maricopa country; according to Wikipedia, it's 62% of the state's total population, so lots, but definitely not all; and according to this other list of data centres, it has most (but still not all) of Arizona's data centers: https://www.datacenters.com/locations/united-states/arizona

    Either way, whoever made this blog post, wasn't paying quite close enough attention to the sources for my taste. Don't mind people using ChatGPT as a search engine (it's better than Google these days, after all), but this does feel like a blog that was vibed, not one that was carefully curated.

    Now, if the circleofblue.org claim about 905 million gallons is true, I can compare it to the claim on the hopefully-trustworthy arizona.edu domain that "Arizona used 7.0 million acre-feet of water in 2017": https://mapazdashboard.arizona.edu/article/arizonas-water-us... and the state population of 7,582,384 and can see this is very close to approximately one acre-foot of water per person per year, but I don't need to be approximated when I can do an exact calculation in Wolfram Alpha and get 300,824 gallons/person/year: https://www.wolframalpha.com/input?i=7+million+acre-feet+%2F...

    This makes 905 million gallons/year equivalent to 3,008 people, not 30k, but remember this also includes all the other industry, farming, etc.: https://www.wolframalpha.com/input?i=%28905+million+gallons%...

    But the two really important parts here are (1): according to the previously mentioned map of Arizona's data centres and circleofblue.org link, that's for all 108 data centres across Arizona not just one; (2) 102 of the 108 data centres are in Phoenix, which has a population of about 1.6 million and isn't going to notice the impact of 30k, let alone 3k, extra residents.

    (But then, can I trust circleofblue.org and datacenters.com? Is anything on the internet trustworthy any more?)