I was under the impression data centers use closed loop cooling.
> Many data centers rely on evaporative cooling, or “swamp cooling,” where warm air is drawn through wet pads. Data centers typically evaporate about 80% of the water they draw, discharging 20% back to a wastewater treatment facility, according to Shaolei Ren, an associate professor of electrical and computer engineering at the University of California, Riverside.
I did some research on additional cost of water + increased efficiency of the condenser, but it's not just that. The water needs to be treated, otherwise it leaves way too much sediment.
By the way "spray the condenser" technology is very very rare because it's pretty much worst of both worlds and nowhere near as good or efficient as a cooling tower but much more maintenance than a dry cooler + compressor. Typically for high efficiency modern sites you'd be looking at cooling towers or dry cooler + compressor for water facilities or spray the water directly onto the air (direct or indirect adiabatic) for air based facilities.
To complicate things many (typically city DCs/Colos/ enterprise facilities) are air based facilities that convert to water by using heat exchangers in the datahalls.