short answer: many datacenters have evaporative coolers that shove the water into the air

Yeah anything that's flushed through dirty industrial cooling pumps is going to pick up lubricants, dust, pesticide, microplastics from parts rubbing against each other, basically all the industrial stuff that works it's way into the system which will get worse with age, and they'll have to put nasty chemicals in it to keep slime from growing.

Basically it's not drinkable and you wouldn't want to shower in it and nothing except slime can live it until its diluted enough.

Will they clean it before dumping it back into the environment every time they flush the system? The answer is no. They won't.

And the idea that it won't use that much water because they'll "recycle" it in a closed system is also bullshit. They will have to flush it all the time because water that's kept like that will foul no matter what you to do it and it will start to clog filters and cause issues. So yeah lots and lots of clean water in and lots and lots of nasty water coming out.

Oh yeah, and when the dumped dirty water evaporates, all the contaminates are left on the ground and will start to concentrate until it starts to be a bigger and bigger problem. It will get blown around into people's yards and crops and into food, pets, etc.

"Chillers and cooling towers are at the heart of most large data center cooling setups. The chiller cools down water, dropping its temperature before it heads to CRAH units or other cooling coils.

Cooling towers push this heat out to the open air, usually by evaporating water. Pairing these together lets chilled water systems handle much bigger loads than just using CRAC units alone.

Key components include:

• Chillers: Make chilled water for cooling coils
• Cooling towers: Get rid of heat from the chiller’s condenser water loop
• Pumps: Move water around between units and throughout the system

Chilled water systems are efficient and can scale up, but they do need a big upfront investment and regular maintenance. They’re the go-to for hyperscale and enterprise data centers where uptime and energy use really matter."

In industrial cooling applications, chilled water is run over massive radiators to dissipate heat more efficiently. This usually causes a good portion of the water to be evaporated. The problems with these massive data centers is that they can pump millions of gallons of groundwater a day only to be evaporated to the atmosphere. They end up pumping more groundwater than can be restored naturally, causing groundwater levels to fall which leads to all sorts of other issues.

Technically it's been used for light industrial purposes, which makes it non-potable after usage. It needs to be run through the treatment and testing cycle again to be fit for human consumption.

That would be a bigger issue if people were expecting to drink from the cooling tap, or if most of them didn't use grey water to begin with.

The water has moved through tubes not necessarily rated for human consumption, and exposed to moderate temperatures.
Most is used in the construction of the datacenters or for air conditioners. It's not used per query at all.