To be clear, all thermal plants - be they nuclear, fossil fuel, biofuel, etc. - require water for cooling. But this doesn't need to be freshwater, many nuclear plants are cooled with seawater. In non-costal arid areas, nuclear plants can be cooled with sewer water: https://en.wikipedia.org/wiki/Palo_Verde_Nuclear_Generating_...

Electricity demand is concentrated in population centers, which themselves require water and produce sewage as a byproduct. Thus it's pretty rare for a place with strong electricity demand to simultaneously have a shortage of water available for cooling. In places with limited freshwater supply, this results in plants using wastewater. Again, thermal plants of all kinds need cooling. Nuclear changes nothing relative to the status quo in this regard.