I am in SE Iowa and its been an Extremely hot & dry summer. I use a concrete bird bath near my hives & just put water in it. I have seven hives & 2 bee trees. They drink the three gallon of water in about a day.
I then added a plastic paint roller tray that holds about a gallon. First I put pieces of wood in them so bees could get out of the water when they fell in. I still had a few bees drown so I tried an experiment with corn cobs. I found that the bees really like the corn cobs because the cobs are like a wick & the bees can sit on top of the cob & drink. This "watering hole" is very busy from about 7 am until dusk. I fill it every day ( after rinseing it out) Just wandered if other beekeepers water their bees!