Comment by motionlessveloc
3 hours ago
I don't really understand the hand-wringing about data centers and water. Unlike fossil fuels, when you "use" water, it doesn't go away, it goes back out into the environment. And since DCs use it for cooling, not some industrial process, it doesn't even contaminate the water in any meaningful way.
The one exception is if they're using fossil water pumped from aquifers, which doesn't renew (back into the aquifer that is), but nobody seems to bother to make the distinction.
True if you're using a closed-loop system. But if you're using evaporative cooling (which is the main cause for concern) then the place where the water 'comes back into the environment' may be quite far away (at least in a useful sense).
I think the bigger issue with water usage ( if it's actually an issue ) is when the system is not able to handle the additional demand ( drying up wells, etc. ) Especially during the summer where water supply is already strained in some areas.
Yes water goes eventually back into circulation but that does not help in the place where the system is already at it's limit
20-25% of the water consumed for evaporative cooling becomes contaminated waste water. It is used to clean out the residue left behind by the 75-80% of the consumed water that is evaporated.
The contaminants consist of dissolved solids and minerals that were in the incoming water, plus additives such as anti-scalers, corrosion inhibiters, and antibacterials.
How much additive gets in there? Is it more or less contaminated than normal sewage? A reasonable amount of treatment is part of the water bill.
The excess minerals don't worry me much.
I would love to see a real breakdown of aquifer water usage.
IMO the water thing is a distraction. It gets people quibbling over water instead of asking bigger questions about the data center.
Mostly, but not entirely. It is a huge issue in the Southwest, and it seems like a lot of DCs are being proposed and/or built in areas where water is far from abundant.
Fresh water supply has been on a downward trend for years. We are already looking at a future without enough fresh water, before the new datacenters come into play. The datacenters are being installed in some of the driest areas of the country that were already water stressed. In some cases they can also contaminate local water systems.
I’m not disagreeing with that but it fundamentally feels like a misdirection. It’s easily hand waved away eg “it uses less than a golf course” and yet it’s still a constant media talking point.
Your use of "into the environment" is too broad.
If you pump water out of one watershed into another, perhaps via evaporation and wind transport, then you better expect the downstream users, deprived of their water, to complain.
For example, the upstream users of water from the Colorado use so much that Colorado River Delta is nearly always dry. Or read about the California water wars.
Further, increased competition for surface water raises prices, which encourages additional aquifer extraction.
The problem in California is that competition for water doesn't raise prices. Much of our water supply is allocated based on property rights rather than as a commodity so prices for some users remain artificially lower than the market price. This causes waste and shortages. Eventually we'll have to reform the system but there's no political will to do so.
The water for the datacenter comes from the same place residents, farmers, etc get their water. If there is already not a lot of water, the datacenter can cause running out of water. Sending used water downstream doesn't magically reappear upstream.
In some cases there is no stream involved at all, which is more problematic, but is pumped from groundwater.