Only in Los Angeles. Some folks up in the Valley wanted to disassociate themselves from the grittiness (I assume) of Van Nuys, so they had the city slap a new label on their neighborhood. But it was never official! There is no Lake Balboa!
Kind of like there never was any Lansing.
This brings up all my favorite questions: What is a city? Who decides what is and isn't a neighborhood? What's more powerful: the will of the people, or the bureaucratic responsibilities of their elective representatives? Just because there's technically no Lake Balboa, the people "there" have been using that name for years ... so isn't it really Lake Balboa?
What's in a name?