Geesh..Earnhardt is so wicked spoiled in the summer months here in SC,that anything above 85,he's squawking to come in where its cool in AC. He is never outside in the heat of the day.And Trapp & Jasper will also follow suit.
The sunporch is cooled also,so it is a place they can be during the day if they choose.
The garage door is left open,and fans are running if we are to leave,and they are outside,they can at least go in on cool cement floor to be out of the elements.
But for outside purposes,when they are out in summer months there are water bowls (reservoir types you see in Walmart) plus crocks we use.I do make large ice blocks for the crocks which keep very well,giving if they are kept in a shaded area.
One of the things we did discover last summer was using a cooler filled with water,and large blocks of ice,if we know we will be gone for longer than usual,which is placed way up at the far end of the yard under one of the magnolia trees.
We are very lucky that we have the trees we do,they provide lots of shade out back,so much shade that grass is absent from much of the yard right here by the back door.
I've thought about one of the water fountains,that the links have been posted for, but Earnhardt needs something deeper,he makes a huge mess when he drinks,I am afraid I would be cleaning up more water than I do now,if it was inside the house.
he would demolish the place. He likes to be out and playing. The neighbor reaches over the fence and pets him and Mom comes by and says hi sometimes (they are only a mile away). Maybe this is the incentive to build a sun room 
) but anyway in the summer I fill the reservoir with ice cubes so it stays cool for the day and that way the dogs cant scuba dive for the ice cubes and make a mess all over my house!