A bubbler is a common term used mainly in the Midwest region of the United States, referring to drinking fountains.
I believe that the slang became popular due to the creation of a drinking fountain that bubbled water out in a different manner than a traditional drinking fountain, although I do not know exactly which way this was.
It may be
nothing, but the
name Ford comes into my mind when I say this.
Wisconsin citizens' use of this word, and other abnormal slangs led to a
study into how Wisconsinites speak in 2005 or
06.