Foot baths work very well. You don't have to dip their feet. They will just stand in the water. Their blood vessels in the legs and feet while standing in water will serve to cool their body temperature.
I wouldn't sprinkle ice if there is bedding as that will just melt, make the bedding wet causing mold/fungus and give a good environment for coccidia to reproduce.
For the foot baths, I use big rubber feed tubs with a frozen water bottle floating in the water. I refill water bottles and freeze them.
Having the right breed of chicken for hot climates will negate the need to worry.