Portland has fountains scattered throughout the city. What makes them different from other city fountains? It's legal to go in them, it's actually encouraged. Fountains are actually designed to be enjoyed in that manner. Some are made for wading in, some for swimming in, some for running through.
There are also the benson bubblers. "In 1912, Simon Benson, lumberman and civic leader, commissioned 20 drinking fountains with a $10,000 gift. He wanted to offer loggers something cold on the streets to quench their thirst. Benson once said that after the fountains were installed, saloon sales decreased 40%. "
So, if you're ever thirsty or hot in Portland, there's no reason to suffer. Some newer fountains now even have built in bowls for dogs.