We have trough and large cup waterers so that when it's hot, the chickens can dip their entire beaks and waddles in the water to help them cool off. No nipple waterers for us.
They won't die without ice in the waterers when it's 83° but it's nice for them to have the cool water to dip in, and it encourages them to drink.
One of our EEs hates hot weather. She is the first to hold her wings out and pant. When that happens, it's our cue to set frozen blocks of ice in tubs all around the pens for the chickens to stand on. She gets right up on one the minute we set it down.
During the hot months we keep a chest freezer full of these ice tubs and swap them out for fresh ones several times as they melt during the day. We have lots of ways of helping the flock keep cool but the ice tubs are the most effective. Chicken life in the desert!