Preparing for heat wave

[Kriscam]

Here's an active thread on this problem: https://www.backyardchickens.com/threads/how-to-keep-chickens-cool-in-upcoming-heat-wave.1477756/

Short version:

Shade,
Electrolytes,
PLAIN WATER TOO,
Access to ground they can dig in so that they can reach a cooler layer (my central NC chickens dig down to the level of their backs on hot afternoons),
An ice block in a pan,
Misters and/or fans as appropriate to circumstances.

Frozen treats are debatable.

I addition to other measures, I have a large feed dish and rotate frozen water bottles throughout the day. It has a couple of bricks just below the surface of the water that they stand on to cool down. I got the brick idea from another thread and it works great. A wet towel and a box fan make a decent swamp cooler.