Ice is one of the two things they sell at Burning Man. (Officially. In reality there are a few more things that they sell, but the 'only two things' label has

Ice is one of the two things they sell at Burning Man. (Officially. In reality there are a few more things that they sell, but the 'only two things' label has stuck). Edit: Also, you don't need Ice for a swamp cooler. You don't even need cold water. The water temperature doesn't really matter, as the temperature drop comes from the evaporation, not the water temperature.